RNA interference (RNAi) is a promising new tool for insect pest control. The document discusses RNAi mechanism and methodology for delivering dsRNA to insects. It then provides several case studies showing successful control of various insect pests by feeding them plant material expressing dsRNA targeting important insect genes. Studies demonstrated reduced survival, growth, and fecundity in insect species like cotton bollworm, whitefly, aphid, and spider mite through RNAi mediated gene silencing. This technique has potential for development as an environmentally friendly alternative to chemical pesticides.
This document provides an overview of current and future RNAi applications in plants. It discusses using RNAi to engineer resistance in plants against various pathogens like nematodes, insects, fungi, viruses, and parasitic weeds. It also discusses using RNAi to manipulate plant metabolism to improve industrial traits like fiber quality and oil content, or nutritional value by increasing carotenoids, amylose content, and reducing gluten proteins harmful to celiac disease patients. Specific examples demonstrating successful RNAi-mediated resistance or trait improvement in crops are provided.
RNA interference (RNAi):A therapeutic strategy for aquacultureidrish123
The document discusses RNA interference (RNAi) as a therapeutic strategy for aquaculture. It describes how RNAi works through a two-step mechanism involving initiation by the enzyme Dicer and effector stage involving the RISC complex. Some successful implementations of RNAi in aquaculture are presented, including reducing mortality from WSSV in shrimp through intramuscular injection of siRNA. The document outlines developing RNAi therapies and applications in aquaculture but also notes limitations such as effective delivery and off-target effects that require further study.
This document provides an overview of RNA interference (RNAi) and its potential applications for crop improvement. It discusses how RNAi works as a gene silencing mechanism, mediated by small non-coding RNAs like microRNAs and short-interfering RNAs. The document outlines how RNAi can be used to alter traits in crops through genetic engineering approaches like developing RNAi constructs targeted to specific genes. It reviews how RNAi has been successfully applied to modify traits related to nutrition, stress tolerance, morphology and more in various plant species. However, it notes that RNAi crops may also pose some biosafety risks that require assessment.
This document discusses RNA interference (RNAi) in plants. It begins by defining RNAi as a biological process where RNA molecules inhibit gene expression by targeting mRNA. It then describes the key components of RNAi - microRNAs, small interfering RNAs, the RISC complex and related enzymes. The document explains the four mechanisms by which siRNAs and miRNAs regulate gene expression, including cleavage, translation inhibition, transcriptional silencing and mRNA degradation. It provides examples of using RNAi technology in plants against insects and pathogens. The document concludes by discussing potential future applications of RNAi, such as developing RNA-based biopesticides and using clay nanosheets to topically deliver RNAi for sustained plant virus protection.
An introduction to RNAi technology - Petr Svoboda - Institute of Molecular Ge...OECD Environment
10-12 April 2019: The OECD Conference on RNAi based pesticides provided an overview on the current status and future possibilities for the regulation of externally applied dsRNA-based products that are proposed for use as pesticides. The event facilitated exchanges between policy makers, academia, industry on their implications in health, environment, and regulation.
This is a presentation slide about cellular RNA interference process and RNA interference technology. Contains basic information about biology of cellular RNA interference processes and its discovery, and RNA interference technology. Also gives you the history and development of in-vitro and in-vivo technologies for applicability of RNA interference technology.
siRNA synthesis, siRNA libraries, siRNA delivering techniques, Electroporation, viral transfection methods, Advantages and disadvantages of RNA interference technology.
details about the preliminary and pre-clinical experiments of RNA interference as well as clinical trials of RNA interference.
RNA interference (RNAi) is a biological process where RNA molecules inhibit gene expression by destroying mRNA. It was discovered as gene silencing in plants and nematodes. RNAi is triggered by double-stranded RNA being cut into small interfering RNAs that target homologous mRNAs for degradation. This protects against viruses and regulates genes. RNAi has many applications, including modulating HIV replication and treating cancer by silencing viral or other genes. It is a powerful new genetic tool with potential for therapeutics.
RNA interference is a mechanism by which small RNA molecules like microRNA and siRNA regulate gene expression by binding to mRNA and preventing protein production. This mechanism is important for immunity and controlling gene expression. It was discovered in 1998 by Fire and Mello through experiments in C. elegans showing that double-stranded RNA, but not single stranded, could efficiently silence genes. RNAi has many applications in biotechnology, functional genomics, and medicine.
This document provides an overview of current and future RNAi applications in plants. It discusses using RNAi to engineer resistance in plants against various pathogens like nematodes, insects, fungi, viruses, and parasitic weeds. It also discusses using RNAi to manipulate plant metabolism to improve industrial traits like fiber quality and oil content, or nutritional value by increasing carotenoids, amylose content, and reducing gluten proteins harmful to celiac disease patients. Specific examples demonstrating successful RNAi-mediated resistance or trait improvement in crops are provided.
RNA interference (RNAi):A therapeutic strategy for aquacultureidrish123
The document discusses RNA interference (RNAi) as a therapeutic strategy for aquaculture. It describes how RNAi works through a two-step mechanism involving initiation by the enzyme Dicer and effector stage involving the RISC complex. Some successful implementations of RNAi in aquaculture are presented, including reducing mortality from WSSV in shrimp through intramuscular injection of siRNA. The document outlines developing RNAi therapies and applications in aquaculture but also notes limitations such as effective delivery and off-target effects that require further study.
This document provides an overview of RNA interference (RNAi) and its potential applications for crop improvement. It discusses how RNAi works as a gene silencing mechanism, mediated by small non-coding RNAs like microRNAs and short-interfering RNAs. The document outlines how RNAi can be used to alter traits in crops through genetic engineering approaches like developing RNAi constructs targeted to specific genes. It reviews how RNAi has been successfully applied to modify traits related to nutrition, stress tolerance, morphology and more in various plant species. However, it notes that RNAi crops may also pose some biosafety risks that require assessment.
This document discusses RNA interference (RNAi) in plants. It begins by defining RNAi as a biological process where RNA molecules inhibit gene expression by targeting mRNA. It then describes the key components of RNAi - microRNAs, small interfering RNAs, the RISC complex and related enzymes. The document explains the four mechanisms by which siRNAs and miRNAs regulate gene expression, including cleavage, translation inhibition, transcriptional silencing and mRNA degradation. It provides examples of using RNAi technology in plants against insects and pathogens. The document concludes by discussing potential future applications of RNAi, such as developing RNA-based biopesticides and using clay nanosheets to topically deliver RNAi for sustained plant virus protection.
An introduction to RNAi technology - Petr Svoboda - Institute of Molecular Ge...OECD Environment
10-12 April 2019: The OECD Conference on RNAi based pesticides provided an overview on the current status and future possibilities for the regulation of externally applied dsRNA-based products that are proposed for use as pesticides. The event facilitated exchanges between policy makers, academia, industry on their implications in health, environment, and regulation.
This is a presentation slide about cellular RNA interference process and RNA interference technology. Contains basic information about biology of cellular RNA interference processes and its discovery, and RNA interference technology. Also gives you the history and development of in-vitro and in-vivo technologies for applicability of RNA interference technology.
siRNA synthesis, siRNA libraries, siRNA delivering techniques, Electroporation, viral transfection methods, Advantages and disadvantages of RNA interference technology.
details about the preliminary and pre-clinical experiments of RNA interference as well as clinical trials of RNA interference.
RNA interference (RNAi) is a biological process where RNA molecules inhibit gene expression by destroying mRNA. It was discovered as gene silencing in plants and nematodes. RNAi is triggered by double-stranded RNA being cut into small interfering RNAs that target homologous mRNAs for degradation. This protects against viruses and regulates genes. RNAi has many applications, including modulating HIV replication and treating cancer by silencing viral or other genes. It is a powerful new genetic tool with potential for therapeutics.
RNA interference is a mechanism by which small RNA molecules like microRNA and siRNA regulate gene expression by binding to mRNA and preventing protein production. This mechanism is important for immunity and controlling gene expression. It was discovered in 1998 by Fire and Mello through experiments in C. elegans showing that double-stranded RNA, but not single stranded, could efficiently silence genes. RNAi has many applications in biotechnology, functional genomics, and medicine.
RNA interference Activity in Glassy-winged Sharpshooter Cells and Whole Insec...huyng
This document summarizes research on inducing RNA interference (RNAi) activity in glassy-winged sharpshooter (GWSS) cells and whole insects. Key findings include:
1) Different RNAi inducers (dsRNA, siRNA, hairpin loops) were tested in GWSS cells, with dsRNA proving most effective at reducing target gene expression.
2) Injection of dsRNA corresponding to endogenous genes into GWSS insects reduced mRNA levels of those genes, indicating RNAi activity.
3) Efforts are underway to generate transgenic plants expressing GWSS dsRNAs in xylem to study RNAi effects through insect feeding.
The document discusses RNA interference (RNAi) as a potential tool for insect pest management. It provides an overview of RNAi, including the discovery of RNAi, how small RNA molecules are central to the process, and the different RNAi pathways. It also discusses challenges to applying RNAi for insect control and examples of studies using plant-expressed RNAi to target different insect pests. The conclusion states that RNAi is a target-specific, non-toxic tool that could help with resistance management through gene silencing.
siRNA and miRNA both regulate gene expression, but through different mechanisms. siRNA targets specific gene sequences, while a single miRNA can regulate many genes. siRNA is found in plants, fungi, and insects but not mammals, which have other antiviral responses. miRNA are small non-coding RNAs around 22 nucleotides long that bind to mRNA to repress translation or promote degradation. They play important roles in development, physiology, and disease when their expression is dysregulated.
RNA Interference(RNAi) is a conserved biological response of eukaryotes against double-stranded RNA causing silencing of the gene expression. This mechanism has an important role in defending cells against viral genes and transposons. RNAi technology has become the latest "next big thing," progressing from a barely understood colour silencing mechanism found in flowers to a powerful tool that is going to become a new therapeutic tool for treating illnesses ranging from AIDS to cancer to Huntington’s disease. Even more exciting is the potential of RNAi in agriculture where it has provided a way to control pests and diseases as well as increase nutritional value of food.
CRISPR is a powerful new tool for genome editing that allows targeted modifications to genes. It utilizes the Cas9 enzyme to cut DNA at a specific site guided by a short RNA molecule. This summary will discuss the history and mechanisms of CRISPR/Cas9 and its applications in biotechnology and agriculture. CRISPR represents a major breakthrough that will revolutionize genetic engineering by enabling precise edits to genomes. However, further refinement is needed to address issues such as off-target effects. Overall, CRISPR technology holds tremendous promise for developing improved crop traits.
Creative biogene-The Extended Applications of RNAicreative biogene
This document discusses RNA interference (RNAi) and its applications. It provides an overview of RNAi, including its discovery in the 1990s and the different types of small silencing RNAs involved like siRNAs, miRNAs, and piRNAs. The document then outlines some key aspects of RNAi like its specificity and potency. It also discusses the various applications of RNAi, such as gene knockdown, functional genomics, and therapeutics. Finally, it describes the custom RNAi services offered by Creative Biogene, including siRNA, shRNA, and miRNA design/synthesis as well as transfection optimization and establishment of stable cell lines.
RNA interference (RNAi) is a biological process in which RNA molecules inhibit gene expression, typically by causing the destruction of specific mRNA molecules. Historically, it was known by other names, including co-suppression, post-transcriptional gene silencing (PTGS), and quelling. Only after these apparently unrelated processes were fully understood did it become clear that they all described the RNAi phenomenon. Andrew Fire and Craig C. Mello shared the 2006 Nobel Prize in Physiology or Medicine for their work on RNA interference in the nematode worm Caenorhabditis elegans, which they published in 1998. Since the discovery of RNAi and its regulatory potentials, it has become evident that RNAi has immense potential in suppression of desired genes. RNAi is now known as precise, efficient, stable and better than antisense technology for gene suppression. Two types of small ribonucleic acid (RNA) molecules – microRNA (miRNA) and small interfering RNA (siRNA) – are central to RNA interference. RNAs are the direct products of genes, and these small RNAs can bind to other specific messenger RNA (mRNA) molecules and either increase or decrease their activity, for example by preventing an mRNA from producing a protein. RNA interference has an important role in defending cells against parasitic nucleotide sequences – viruses and transposons. It also influences development.
RNA interference (RNAi): Cellular process by which an mRNA is targeted for degradation by a dsRNA with a strand complementary to a fragment of such mRNA.
SMi is proud to present its 6th conference on RNAi, miRNA and siRNA which shall tackle some of the most prominent issues that stand in the way of the successful harnessing of the vast potential that the process possesses. RNAi is still a new and exciting area of pharmaceutical development, however significant progress is required in certain areas, in achieving successful targeted delivery and tackling off targeting as two examples.
This conference will display some of the most promising results achieved; from structural determination through to specific therapeutic applications, clinical trial considerations and negotiating the regulatory minefield, attendees can be sure to expect an invaluable learning and networking experience.
RNA interference (RNAi) is a natural process in cells that uses small RNA molecules to regulate gene expression. Craig Fire and Andrew Mello discovered RNAi in 1998 through their experiments injecting double-stranded RNA into C. elegans worms. They found this silenced or interfered with the expression of genes with complementary RNA sequences. RNAi has important roles in defending against viruses and regulating development, with the small RNAs binding to messenger RNAs to decrease their activity. It has potential applications in gene therapy, functional genomics, agriculture, and more.
This document provides an overview of RNA interference (RNAi) including its mechanism, applications, and methods for delivering small interfering RNA (siRNA). It discusses how dsRNA is processed by the enzyme Dicer into siRNAs which are incorporated into the RISC complex to degrade complementary mRNA. Viral vectors, liposomes, nanoparticles, and chemical modifications are described as methods used to deliver exogenous siRNAs. The document outlines both the therapeutic potential of RNAi and challenges associated with effective siRNA delivery.
This document discusses RNA interference (RNAi) and its mechanisms. It can be summarized as follows:
1. RNAi is a process where double-stranded RNA causes degradation of homologous mRNA sequences. It was discovered in 1998 and is found across many organisms.
2. The RNAi pathway involves conversion of dsRNA to siRNAs by the enzyme Dicer. siRNAs are incorporated into the RISC complex containing Argonaute proteins. RISC then cleaves and destroys homologous mRNA targets.
3. miRNAs are endogenous single-stranded RNAs that regulate gene expression at the translation level by preventing ribosome binding. They are processed from hairpin precursors by the enzymes Dro
Principle and method of RNAi-Creative BiogeneDonglin Bao
In recent years, studies have shown that mRNA will occur specific degradation if dsRNA which is composed of sense RNA and antisense RNA from mRNA is transferred into the cell, eventually it leads to target genes silence. The post-transcriptional gene silencing (PTGS) is described as RNAi.
RNA interference (RNAi) is a biological process where RNA molecules inhibit gene expression, typically by causing the destruction of specific mRNA molecules. It was first discovered in plants and nematodes but is found in most eukaryotic organisms. The process involves specialized enzymes that cut long RNA molecules into short interfering RNAs which then guide other proteins to destroy any RNAs of the same sequence. RNAi plays important roles in regulating genes and defending against foreign DNA and RNA. It has many applications for studying gene function and as a potential therapeutic approach for diseases like cancer and infections.
This document discusses RNA interference (RNAi), a biological mechanism that leads to post-transcriptional gene silencing triggered by double-stranded RNA molecules. It was discovered in 1998 by Fire and Mello, who received the Nobel Prize for this work. The mechanism involves double-stranded RNA being processed by the enzyme Dicer into small interfering RNAs that integrate into the RNA-induced silencing complex and guide mRNA degradation. RNAi can be induced by synthetic siRNAs or endogenous microRNAs and represents a powerful tool for studying gene function and developing therapies.
RNA interference (RNAi) is a gene silencing mechanism that can be used for crop improvement. It involves introducing double-stranded RNA molecules that are then processed by an enzyme called Dicer into small interfering RNAs (siRNAs). These siRNAs are incorporated into a protein complex called RISC which uses them to guide degradation of complementary mRNA targets. This targeted degradation allows for precise control of gene expression. RNAi has advantages over traditional genetic modification techniques as it provides an efficient way to silence individual or multiple genes without causing abnormalities. It also shows systemic silencing effects and can be amplified. RNAi holds great potential for improving important agronomic traits in crops.
RNA interference (RNAi) is a gene silencing mechanism induced by double-stranded RNA that has been widely used to analyze gene function. In plants, RNAi is often achieved through hairpin RNA transgenes and has advantages over other methods. It allows for regulated suppression of gene families and offers a tool for efficient, high-throughput analysis of gene function in crop plants.
RNAi interuption mechanism and applicationSumeena Karki
RNA interference is a natural mechanism that inhibits gene expression. It was first discovered accidentally in 1990 when researchers trying to increase pigmentation in petunias found that introduced homologous RNA led to less pigmentation. Further work found similar mechanisms in plants and fungi termed cosuppression and quelling. Craig Mello and Andrew Fire's 1998 paper demonstrating gene silencing in C. elegans using double stranded RNA led to the coining of the term RNAi. The mechanism involves Dicer and Drosha enzymes processing trigger RNA into siRNAs which are loaded into the RISC complex containing Argonaute proteins to degrade complementary mRNA, silencing gene expression. RNAi plays roles in gene regulation, genome stability, and provides therapeutic tools for disease
This document discusses RNA interference (RNAi) mediated gene silencing in plants. It describes how small interfering RNAs (siRNAs) and microRNAs (miRNAs) are central to RNAi and can direct the degradation of messenger RNA (mRNA) to decrease gene expression. The document outlines the key stages of the RNAi mechanism and roles of proteins involved like Dicer and RISC complexes. It provides examples of how RNAi has been used to increase crop traits like shelf life, virus resistance, and fruit development.
RNAi is a powerful, conserved biological process through which the small, double-stranded RNAs specifically silence the expression of homologous genes, largely through degradation of their cognate mRNA.
RNA interference (RNAi) is a technique that uses double-stranded RNA to silence gene expression. It involves introducing dsRNA into a cell that is complementary to the target mRNA. This dsRNA is processed by the Dicer enzyme into siRNAs which are incorporated into the RISC complex. The RISC complex uses the siRNA to identify and cleave the target mRNA, preventing it from being translated into protein. RNAi provides a valuable tool for studying gene function and has applications in biotechnology, agriculture, and medicine by allowing researchers to knock down gene expression.
1. siRNA and miRNA are types of non-coding RNAs that play important roles in post-transcriptional gene regulation. siRNA induces gene silencing through RNA interference, while miRNA binds to target mRNAs to inhibit translation.
2. Both siRNA and miRNA have shown promise in developing therapies for diseases like cancer, asthma, neurodegenerative disorders, and viral infections by silencing genes involved in disease pathways. Delivery methods continue to be improved to enhance their therapeutic potential.
3. The key differences between siRNA and miRNA are their biogenesis, targeting specificity, and mechanisms of gene regulation. siRNA is synthesized from long double-stranded RNA and can perfectly complement target mRNAs, while miRNA originates from
RNA interference Activity in Glassy-winged Sharpshooter Cells and Whole Insec...huyng
This document summarizes research on inducing RNA interference (RNAi) activity in glassy-winged sharpshooter (GWSS) cells and whole insects. Key findings include:
1) Different RNAi inducers (dsRNA, siRNA, hairpin loops) were tested in GWSS cells, with dsRNA proving most effective at reducing target gene expression.
2) Injection of dsRNA corresponding to endogenous genes into GWSS insects reduced mRNA levels of those genes, indicating RNAi activity.
3) Efforts are underway to generate transgenic plants expressing GWSS dsRNAs in xylem to study RNAi effects through insect feeding.
The document discusses RNA interference (RNAi) as a potential tool for insect pest management. It provides an overview of RNAi, including the discovery of RNAi, how small RNA molecules are central to the process, and the different RNAi pathways. It also discusses challenges to applying RNAi for insect control and examples of studies using plant-expressed RNAi to target different insect pests. The conclusion states that RNAi is a target-specific, non-toxic tool that could help with resistance management through gene silencing.
siRNA and miRNA both regulate gene expression, but through different mechanisms. siRNA targets specific gene sequences, while a single miRNA can regulate many genes. siRNA is found in plants, fungi, and insects but not mammals, which have other antiviral responses. miRNA are small non-coding RNAs around 22 nucleotides long that bind to mRNA to repress translation or promote degradation. They play important roles in development, physiology, and disease when their expression is dysregulated.
RNA Interference(RNAi) is a conserved biological response of eukaryotes against double-stranded RNA causing silencing of the gene expression. This mechanism has an important role in defending cells against viral genes and transposons. RNAi technology has become the latest "next big thing," progressing from a barely understood colour silencing mechanism found in flowers to a powerful tool that is going to become a new therapeutic tool for treating illnesses ranging from AIDS to cancer to Huntington’s disease. Even more exciting is the potential of RNAi in agriculture where it has provided a way to control pests and diseases as well as increase nutritional value of food.
CRISPR is a powerful new tool for genome editing that allows targeted modifications to genes. It utilizes the Cas9 enzyme to cut DNA at a specific site guided by a short RNA molecule. This summary will discuss the history and mechanisms of CRISPR/Cas9 and its applications in biotechnology and agriculture. CRISPR represents a major breakthrough that will revolutionize genetic engineering by enabling precise edits to genomes. However, further refinement is needed to address issues such as off-target effects. Overall, CRISPR technology holds tremendous promise for developing improved crop traits.
Creative biogene-The Extended Applications of RNAicreative biogene
This document discusses RNA interference (RNAi) and its applications. It provides an overview of RNAi, including its discovery in the 1990s and the different types of small silencing RNAs involved like siRNAs, miRNAs, and piRNAs. The document then outlines some key aspects of RNAi like its specificity and potency. It also discusses the various applications of RNAi, such as gene knockdown, functional genomics, and therapeutics. Finally, it describes the custom RNAi services offered by Creative Biogene, including siRNA, shRNA, and miRNA design/synthesis as well as transfection optimization and establishment of stable cell lines.
RNA interference (RNAi) is a biological process in which RNA molecules inhibit gene expression, typically by causing the destruction of specific mRNA molecules. Historically, it was known by other names, including co-suppression, post-transcriptional gene silencing (PTGS), and quelling. Only after these apparently unrelated processes were fully understood did it become clear that they all described the RNAi phenomenon. Andrew Fire and Craig C. Mello shared the 2006 Nobel Prize in Physiology or Medicine for their work on RNA interference in the nematode worm Caenorhabditis elegans, which they published in 1998. Since the discovery of RNAi and its regulatory potentials, it has become evident that RNAi has immense potential in suppression of desired genes. RNAi is now known as precise, efficient, stable and better than antisense technology for gene suppression. Two types of small ribonucleic acid (RNA) molecules – microRNA (miRNA) and small interfering RNA (siRNA) – are central to RNA interference. RNAs are the direct products of genes, and these small RNAs can bind to other specific messenger RNA (mRNA) molecules and either increase or decrease their activity, for example by preventing an mRNA from producing a protein. RNA interference has an important role in defending cells against parasitic nucleotide sequences – viruses and transposons. It also influences development.
RNA interference (RNAi): Cellular process by which an mRNA is targeted for degradation by a dsRNA with a strand complementary to a fragment of such mRNA.
SMi is proud to present its 6th conference on RNAi, miRNA and siRNA which shall tackle some of the most prominent issues that stand in the way of the successful harnessing of the vast potential that the process possesses. RNAi is still a new and exciting area of pharmaceutical development, however significant progress is required in certain areas, in achieving successful targeted delivery and tackling off targeting as two examples.
This conference will display some of the most promising results achieved; from structural determination through to specific therapeutic applications, clinical trial considerations and negotiating the regulatory minefield, attendees can be sure to expect an invaluable learning and networking experience.
RNA interference (RNAi) is a natural process in cells that uses small RNA molecules to regulate gene expression. Craig Fire and Andrew Mello discovered RNAi in 1998 through their experiments injecting double-stranded RNA into C. elegans worms. They found this silenced or interfered with the expression of genes with complementary RNA sequences. RNAi has important roles in defending against viruses and regulating development, with the small RNAs binding to messenger RNAs to decrease their activity. It has potential applications in gene therapy, functional genomics, agriculture, and more.
This document provides an overview of RNA interference (RNAi) including its mechanism, applications, and methods for delivering small interfering RNA (siRNA). It discusses how dsRNA is processed by the enzyme Dicer into siRNAs which are incorporated into the RISC complex to degrade complementary mRNA. Viral vectors, liposomes, nanoparticles, and chemical modifications are described as methods used to deliver exogenous siRNAs. The document outlines both the therapeutic potential of RNAi and challenges associated with effective siRNA delivery.
This document discusses RNA interference (RNAi) and its mechanisms. It can be summarized as follows:
1. RNAi is a process where double-stranded RNA causes degradation of homologous mRNA sequences. It was discovered in 1998 and is found across many organisms.
2. The RNAi pathway involves conversion of dsRNA to siRNAs by the enzyme Dicer. siRNAs are incorporated into the RISC complex containing Argonaute proteins. RISC then cleaves and destroys homologous mRNA targets.
3. miRNAs are endogenous single-stranded RNAs that regulate gene expression at the translation level by preventing ribosome binding. They are processed from hairpin precursors by the enzymes Dro
Principle and method of RNAi-Creative BiogeneDonglin Bao
In recent years, studies have shown that mRNA will occur specific degradation if dsRNA which is composed of sense RNA and antisense RNA from mRNA is transferred into the cell, eventually it leads to target genes silence. The post-transcriptional gene silencing (PTGS) is described as RNAi.
RNA interference (RNAi) is a biological process where RNA molecules inhibit gene expression, typically by causing the destruction of specific mRNA molecules. It was first discovered in plants and nematodes but is found in most eukaryotic organisms. The process involves specialized enzymes that cut long RNA molecules into short interfering RNAs which then guide other proteins to destroy any RNAs of the same sequence. RNAi plays important roles in regulating genes and defending against foreign DNA and RNA. It has many applications for studying gene function and as a potential therapeutic approach for diseases like cancer and infections.
This document discusses RNA interference (RNAi), a biological mechanism that leads to post-transcriptional gene silencing triggered by double-stranded RNA molecules. It was discovered in 1998 by Fire and Mello, who received the Nobel Prize for this work. The mechanism involves double-stranded RNA being processed by the enzyme Dicer into small interfering RNAs that integrate into the RNA-induced silencing complex and guide mRNA degradation. RNAi can be induced by synthetic siRNAs or endogenous microRNAs and represents a powerful tool for studying gene function and developing therapies.
RNA interference (RNAi) is a gene silencing mechanism that can be used for crop improvement. It involves introducing double-stranded RNA molecules that are then processed by an enzyme called Dicer into small interfering RNAs (siRNAs). These siRNAs are incorporated into a protein complex called RISC which uses them to guide degradation of complementary mRNA targets. This targeted degradation allows for precise control of gene expression. RNAi has advantages over traditional genetic modification techniques as it provides an efficient way to silence individual or multiple genes without causing abnormalities. It also shows systemic silencing effects and can be amplified. RNAi holds great potential for improving important agronomic traits in crops.
RNA interference (RNAi) is a gene silencing mechanism induced by double-stranded RNA that has been widely used to analyze gene function. In plants, RNAi is often achieved through hairpin RNA transgenes and has advantages over other methods. It allows for regulated suppression of gene families and offers a tool for efficient, high-throughput analysis of gene function in crop plants.
RNAi interuption mechanism and applicationSumeena Karki
RNA interference is a natural mechanism that inhibits gene expression. It was first discovered accidentally in 1990 when researchers trying to increase pigmentation in petunias found that introduced homologous RNA led to less pigmentation. Further work found similar mechanisms in plants and fungi termed cosuppression and quelling. Craig Mello and Andrew Fire's 1998 paper demonstrating gene silencing in C. elegans using double stranded RNA led to the coining of the term RNAi. The mechanism involves Dicer and Drosha enzymes processing trigger RNA into siRNAs which are loaded into the RISC complex containing Argonaute proteins to degrade complementary mRNA, silencing gene expression. RNAi plays roles in gene regulation, genome stability, and provides therapeutic tools for disease
This document discusses RNA interference (RNAi) mediated gene silencing in plants. It describes how small interfering RNAs (siRNAs) and microRNAs (miRNAs) are central to RNAi and can direct the degradation of messenger RNA (mRNA) to decrease gene expression. The document outlines the key stages of the RNAi mechanism and roles of proteins involved like Dicer and RISC complexes. It provides examples of how RNAi has been used to increase crop traits like shelf life, virus resistance, and fruit development.
RNAi is a powerful, conserved biological process through which the small, double-stranded RNAs specifically silence the expression of homologous genes, largely through degradation of their cognate mRNA.
RNA interference (RNAi) is a technique that uses double-stranded RNA to silence gene expression. It involves introducing dsRNA into a cell that is complementary to the target mRNA. This dsRNA is processed by the Dicer enzyme into siRNAs which are incorporated into the RISC complex. The RISC complex uses the siRNA to identify and cleave the target mRNA, preventing it from being translated into protein. RNAi provides a valuable tool for studying gene function and has applications in biotechnology, agriculture, and medicine by allowing researchers to knock down gene expression.
1. siRNA and miRNA are types of non-coding RNAs that play important roles in post-transcriptional gene regulation. siRNA induces gene silencing through RNA interference, while miRNA binds to target mRNAs to inhibit translation.
2. Both siRNA and miRNA have shown promise in developing therapies for diseases like cancer, asthma, neurodegenerative disorders, and viral infections by silencing genes involved in disease pathways. Delivery methods continue to be improved to enhance their therapeutic potential.
3. The key differences between siRNA and miRNA are their biogenesis, targeting specificity, and mechanisms of gene regulation. siRNA is synthesized from long double-stranded RNA and can perfectly complement target mRNAs, while miRNA originates from
This document provides information about InTechOpen, a publisher of open access books. Some key details:
- InTechOpen has published over 2,900 open access books across multiple international authors and editors.
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Antisense rna experiments lead to the discovery ofBruno Mmassy
The document summarizes the discovery of RNA interference (RNAi) through experiments using antisense RNA in C. elegans. Scientists discovered that injecting double-stranded RNA into C. elegans triggered the degradation of homologous mRNA through a process called RNAi. Today, RNAi is a widely used gene silencing technique where exogenous double-stranded RNA is introduced into cells to specifically destroy target mRNA and reduce gene expression.
Rna interference in insect pest managementamoldchokhat
This document discusses RNA interference (RNAi) and its potential applications for insect pest management in agriculture. It provides background on the discovery of RNAi and how it functions as a gene silencing mechanism. The document then explores how RNAi operates in insects and various methods for delivering double-stranded RNA. Both challenges and opportunities for using RNAi to control insect pests are examined, along with prospects like targeting multiple genes simultaneously or combining RNAi with other approaches like Bt toxins.
RNA interference (RNAi) is a mechanism where double-stranded RNA inhibits gene expression. It was discovered in plants, fungi, and animals. The mechanism involves dicer enzymes cleaving long double-stranded RNA into short interfering RNAs (siRNAs). These siRNAs are incorporated into an RNA-induced silencing complex (RISC) which guides the complex to mRNAs with complementary sequences, resulting in their degradation. RNAi has applications in therapeutics for cancer, viruses, and genetic disorders, as well as research in gene function and pathways.
SiRNA and microRNA are important non-coding RNA molecules that regulate gene expression through RNA interference. SiRNA silences specific genes by degrading mRNA, while microRNA causes translational repression or degradation of target mRNAs. Both are involved in many important biological processes but also have applications and challenges for therapeutic use.
Gene silencing techniques for crop improvementJhilickBanerjee
Gene silencing is a technique that aims to reduce or eliminate the production of a protein from its corresponding gene. Gene silencing is the regulation of gene expression in a cell.
Gene silencing can occur during either transcription or translation.
Gene silencing is often considered as “Gene knockdown’ i.e their expression is reduced. In contrast , when genes are knocked out they are completely erased from the organism’s genome and thus have no expression.
Methods used to silence genes include RNAi, CRISPR or siRNA, these reduce the expression of the gene by 70% but do not completely eliminate it.
This document discusses microRNAs (miRNAs), which are small non-coding RNA molecules that regulate gene expression. It provides a brief history of miRNA discovery and defines miRNAs and how they differ from siRNAs. The document highlights that miRNAs are encoded in genomes and bind to mRNAs to repress translation or promote degradation. It notes miRNAs play key roles in processes like cell differentiation and growth. The document also summarizes some of the main functions of miRNAs in controlling gene expression and development.
The IOSR Journal of Pharmacy (IOSRPHR) is an open access online & offline peer reviewed international journal, which publishes innovative research papers, reviews, mini-reviews, short communications and notes dealing with Pharmaceutical Sciences( Pharmaceutical Technology, Pharmaceutics, Biopharmaceutics, Pharmacokinetics, Pharmaceutical/Medicinal Chemistry, Computational Chemistry and Molecular Drug Design, Pharmacognosy & Phytochemistry, Pharmacology, Pharmaceutical Analysis, Pharmacy Practice, Clinical and Hospital Pharmacy, Cell Biology, Genomics and Proteomics, Pharmacogenomics, Bioinformatics and Biotechnology of Pharmaceutical Interest........more details on Aim & Scope).
RNA interference (RNAi) is a biological mechanism that leads to post-transcriptional gene silencing triggered by double-stranded RNA (dsRNA) molecules. It involves small interfering RNAs (siRNAs) and microRNAs (miRNAs) that are processed by Dicer nuclease and loaded into an RNA-induced silencing complex (RISC) which targets and degrades messenger RNAs (mRNAs). The mechanism of RNAi involves dsRNA being cleaved by Dicer into siRNAs which are incorporated into RISC and used as a guide to degrade complementary mRNAs. RNAi has various applications in crop improvement traits like enhanced shelf life, male sterility/fertility, biofortification, aller
INTERFERENCE means the act of interfering with something, here, with RNA. RNAi is an evolutionarily conserved mechanism triggered by dsRNA molecules, to prevent the expression of specific genes or the translation, causes sequence-specific degradation of the targeted mRNA molecules of that particular gene. It was also known as CO-SUPPRESSION, POST TRANSCRIPTIONAL GENE SILENCING [PTGS] in plants and QUELLING in fungi.
Small interfering RNA (siRNA) are double stranded RNA molecules that are 20-25 base pairs in length and silence gene expression through RNA interference. Andrew Fire and Craig Mello discovered RNA interference in 1998 through experiments injecting double stranded RNA into nematode worms, finding it caused gene silencing. The mechanism involves dicer cleaving double stranded RNA into siRNAs which are then loaded into an RISC complex to bind and cleave target mRNAs, preventing protein synthesis from that gene. SiRNA has significance in protecting against viruses, regulating development, and suppressing transcription, and applications in research to determine protein function and potential clinical uses like cancer treatment.
This document discusses RNA interference (RNAi) and its applications in biotechnology. It explains that RNAi is a process where RNA molecules inhibit gene expression by targeting mRNA. It has been used as a gene knockdown technology in various organisms. Examples are given of using RNAi to increase tomato shelf life by silencing genes involved in ripening, creating male sterility in tobacco and tomato, increasing wheat amylose content, and enhancing bacterial disease resistance in plants. The document concludes by listing several references on RNAi applications for controlling insect pests, studying virus-vector interactions, and improving plant nutrition and metabolic engineering.
Antisense RNA technology & its role in crop improvement ppt surendra singhDrSurendraSingh2
This document discusses antisense RNA technology and its role in crop improvement. It begins by introducing antisense RNA as a method for inhibiting gene expression through complementary base pairing. It then discusses various applications of antisense RNA technology in crop improvement, including delaying fruit ripening in tomato and flower senescence in carnation, producing male sterility in petunia, and reducing neurotoxins in crops like khesari. The document concludes by noting that antisense RNA technology is an efficient gene knockdown method that could be useful for genetic improvement in many plant species.
The relationship between humans and insect pests can be viewed as an evolutionary arms race, where each group develops strategies in response to changes in the other over time. Recent advances in genomics have revealed a new potential strategy for humans - gene silencing using RNA interference (RNAi). RNAi involves blocking expression of specific insect pest genes to control populations. While studies show RNAi's effectiveness, challenges remain in delivering dsRNA to target cells and selecting optimal target genes. This document discusses the RNAi process, methods for dsRNA delivery including oral ingestion, and difficulties that must still be addressed to realize RNAi's potential as an effective pest control method.
This presentation provides an overview of RNA interference (RNAi) including its history, components, mechanism, advantages, and applications. It discusses how RNAi involves long double-stranded RNAs being cut by the enzyme Dicer into short interfering RNAs (siRNAs) that then guide the RNA-induced silencing complex (RISC) to degrade messenger RNAs with complementary base sequences, preventing gene expression. The presentation also compares siRNAs and microRNAs (miRNAs), noting similarities in their biogenesis and roles in post-transcriptional gene silencing, while distinguishing their origins, sizes, targets, and effects on mRNA. Recent applications of RNAi modulation of viral replication and gene expression are highlighted.
This document summarizes a study on two genome editing tools: CRISPR/Cas9 and RNAi. CRISPR/Cas9 originated from the adaptive immune system of bacteria and allows for easy editing of DNA at specific locations using an RNA guide and Cas9 enzyme. RNAi utilizes small interfering RNAs to degrade mRNA and silence genes. The document discusses the mechanisms, applications in agriculture, disease modeling and gene therapy, and compares the advantages of CRISPR/Cas9 over RNAi.
Candidate young stellar objects in the S-cluster: Kinematic analysis of a sub...Sérgio Sacani
Context. The observation of several L-band emission sources in the S cluster has led to a rich discussion of their nature. However, a definitive answer to the classification of the dusty objects requires an explanation for the detection of compact Doppler-shifted Brγ emission. The ionized hydrogen in combination with the observation of mid-infrared L-band continuum emission suggests that most of these sources are embedded in a dusty envelope. These embedded sources are part of the S-cluster, and their relationship to the S-stars is still under debate. To date, the question of the origin of these two populations has been vague, although all explanations favor migration processes for the individual cluster members. Aims. This work revisits the S-cluster and its dusty members orbiting the supermassive black hole SgrA* on bound Keplerian orbits from a kinematic perspective. The aim is to explore the Keplerian parameters for patterns that might imply a nonrandom distribution of the sample. Additionally, various analytical aspects are considered to address the nature of the dusty sources. Methods. Based on the photometric analysis, we estimated the individual H−K and K−L colors for the source sample and compared the results to known cluster members. The classification revealed a noticeable contrast between the S-stars and the dusty sources. To fit the flux-density distribution, we utilized the radiative transfer code HYPERION and implemented a young stellar object Class I model. We obtained the position angle from the Keplerian fit results; additionally, we analyzed the distribution of the inclinations and the longitudes of the ascending node. Results. The colors of the dusty sources suggest a stellar nature consistent with the spectral energy distribution in the near and midinfrared domains. Furthermore, the evaporation timescales of dusty and gaseous clumps in the vicinity of SgrA* are much shorter ( 2yr) than the epochs covered by the observations (≈15yr). In addition to the strong evidence for the stellar classification of the D-sources, we also find a clear disk-like pattern following the arrangements of S-stars proposed in the literature. Furthermore, we find a global intrinsic inclination for all dusty sources of 60 ± 20◦, implying a common formation process. Conclusions. The pattern of the dusty sources manifested in the distribution of the position angles, inclinations, and longitudes of the ascending node strongly suggests two different scenarios: the main-sequence stars and the dusty stellar S-cluster sources share a common formation history or migrated with a similar formation channel in the vicinity of SgrA*. Alternatively, the gravitational influence of SgrA* in combination with a massive perturber, such as a putative intermediate mass black hole in the IRS 13 cluster, forces the dusty objects and S-stars to follow a particular orbital arrangement. Key words. stars: black holes– stars: formation– Galaxy: center– galaxies: star formation
The binding of cosmological structures by massless topological defectsSérgio Sacani
Assuming spherical symmetry and weak field, it is shown that if one solves the Poisson equation or the Einstein field
equations sourced by a topological defect, i.e. a singularity of a very specific form, the result is a localized gravitational
field capable of driving flat rotation (i.e. Keplerian circular orbits at a constant speed for all radii) of test masses on a thin
spherical shell without any underlying mass. Moreover, a large-scale structure which exploits this solution by assembling
concentrically a number of such topological defects can establish a flat stellar or galactic rotation curve, and can also deflect
light in the same manner as an equipotential (isothermal) sphere. Thus, the need for dark matter or modified gravity theory is
mitigated, at least in part.
Sexuality - Issues, Attitude and Behaviour - Applied Social Psychology - Psyc...PsychoTech Services
A proprietary approach developed by bringing together the best of learning theories from Psychology, design principles from the world of visualization, and pedagogical methods from over a decade of training experience, that enables you to: Learn better, faster!
Authoring a personal GPT for your research and practice: How we created the Q...Leonel Morgado
Thematic analysis in qualitative research is a time-consuming and systematic task, typically done using teams. Team members must ground their activities on common understandings of the major concepts underlying the thematic analysis, and define criteria for its development. However, conceptual misunderstandings, equivocations, and lack of adherence to criteria are challenges to the quality and speed of this process. Given the distributed and uncertain nature of this process, we wondered if the tasks in thematic analysis could be supported by readily available artificial intelligence chatbots. Our early efforts point to potential benefits: not just saving time in the coding process but better adherence to criteria and grounding, by increasing triangulation between humans and artificial intelligence. This tutorial will provide a description and demonstration of the process we followed, as two academic researchers, to develop a custom ChatGPT to assist with qualitative coding in the thematic data analysis process of immersive learning accounts in a survey of the academic literature: QUAL-E Immersive Learning Thematic Analysis Helper. In the hands-on time, participants will try out QUAL-E and develop their ideas for their own qualitative coding ChatGPT. Participants that have the paid ChatGPT Plus subscription can create a draft of their assistants. The organizers will provide course materials and slide deck that participants will be able to utilize to continue development of their custom GPT. The paid subscription to ChatGPT Plus is not required to participate in this workshop, just for trying out personal GPTs during it.
Discovery of An Apparent Red, High-Velocity Type Ia Supernova at 𝐳 = 2.9 wi...Sérgio Sacani
We present the JWST discovery of SN 2023adsy, a transient object located in a host galaxy JADES-GS
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(June 12, 2024) Webinar: Development of PET theranostics targeting the molecu...Scintica Instrumentation
Targeting Hsp90 and its pathogen Orthologs with Tethered Inhibitors as a Diagnostic and Therapeutic Strategy for cancer and infectious diseases with Dr. Timothy Haystead.
PPT on Alternate Wetting and Drying presented at the three-day 'Training and Validation Workshop on Modules of Climate Smart Agriculture (CSA) Technologies in South Asia' workshop on April 22, 2024.
2. MANAGEMENT OF INSECT PESTS BY RNAi – A NEW TOOL FOR CROP PROTECTION.
ENT 691
SEMINAR PRESENTATION
ON
Major Guide
Dr. M. F. ACHARYA
PROFESSOR & HEAD
DEPARTMENT OF ENTOMOLOGY
JUNAGADH AGRICULTURAL UNIVERSITY
JUNAGADH.
Minor Guide
Dr. L. F. AKBARI
PROFESSOR & HEAD
DEPARTMENT OF PLANT PATHOLOGY
JUNAGADH AGRICULTURAL UNIVERSITY
JUNAGADH.
Speaker
Mr. PRASHANT B. KANERIA
Ph. D. (Agri.) Agril. Entomology
DEPARTMENT OF ENTOMOLOGY
JUNAGADH AGRICULTURAL UNIVERSITY
JUNAGADH.
3. 3
Introduction
RNA interference (RNAi)
Mechanism of RNA interference (RNAi)
Diagrammatic representation of RNAi Mechanism
Cellular mechanism of RNAi pathway
Methodology of dsRNA uptake in insects
Possible methods for mass-production of dsRNA for pest control
The basic levels of RNAi from an insect control
Case Studies
Conclusion
5. Agriculture is the backbone of Indian economy. In India around 70% of the
population earns its livelihood from agriculture. In India, the crop losses due
to insect pests have declined from 23.3 % in post-Green Revolution era to
17.5 % at present.
Chemical pesticides are still the major approach for controlling insect pests,
but they are associated with significant hazards to the environment and
human health.
The alternative commercial biotechnological system relies mostly on the
expression of Bt (Cry toxins). Its effectiveness is threatened by the
development of resistance in some species insects.
As a result, there is an urgent need to develop economically and ecologically
sound alternatives for pest control.
Gene silencing has been suggested as one of the new alternatives to reduce
damage from insect pests
7. RNA interference (RNAi) refers to the ability of double-stranded RNAs to
shut down the expression of a messenger RNA with which they have
sequence in common.
RNA interference (RNAi) is a biological process in
which RNA molecules inhibit gene expression or translation, by neutralizing
targeted mRNA molecules.
Historically, it was known by other names, including co-suppression, post-
transcriptional gene silencing (PTGS), and quelling.
Andrew Fire and Craig C. Mello shared the 2006 Nobel Prize in Physiology
or Medicine for their work on RNA interference in
the nematode worm Caenorhabditis elegans, which they published in 1998.
Since the discovery of RNAi and its regulatory potentials, it has become
evident that RNAi has immense potential in suppression of desired genes.
9. RNAi is an important and natural anti defense mechanism.
Two types of small ribonucleic acid (RNA) molecules – micro
RNA (miRNA) and small interfering RNA (siRNA) – are central
to RNA interference. RNAs are the direct products of genes, and
these small RNAs can bind to other specific messenger
RNA (mRNA) molecules and either increase or decrease their
activity.
Dicer is one of the enzymes involved in RNAi mechanism that is
encoded by a variable number of genes and presents distinct
specificity among organisms
The most recognized RNAi pathways are the siRNA and
miRNA; despite being triggered by different molecules, both
precursors are long double-stranded RNAs (dsRNAs).
10. An siRNA-containing effector complex is referred to as an “RNA-induced
silencing complex” (RISC), and an miRNA-containing effector complex is
referred to as an miRNP(microinterferanceribonucleoprotein).
In these complexes, the regulation is at a post transcriptional level and every
RISC or miRNP contains a member of the Argonaute (Ago) protein family .
For the regulation at the transcriptional level as guided siRNAs, a
specialized nuclear Argonaute-containing complex, known as the RNA-
Induced Transcriptional Silencing complex (RITS) mediates gene silencing
In general, one strand of the short-RNA duplex (the guide strand) is loaded
onto an Argonaute protein at the core of the effectors complexes.
11.
12.
13.
14. 1. siRNAs
Endogenous dsRNA initiates RNAi by activating
the ribonuclease protein Dicer.
Produce double-stranded fragments of 20–25 base
pairs with a 2-nucleotide overhang at the 3' end.
These short double-stranded fragments are called
small interfering RNAs (siRNAs).
These siRNAs are then separated into single
strands and integrated into an active RNA induced
silencing complex (RISC).
After integration into the RISC, siRNAs base-pair
to their target mRNA and induce cleavage of the
mRNA, thereby preventing it from being used as a
translation template.
15.
16. 2. MicroRNAs
MicroRNAs (miRNAs) are genomically encoded non-coding RNAs
that help in regulating gene expression, particularly during
development.
A miRNA is expressed from a much longer RNA-coding gene as a
primary transcript known as a pri-miRNA which is processed, in the cell
nucleus, to a 70-nucleotide stem-loop structure called a pre-miRNA by
the microprocessor complex.
The dsRNA portion of this pre-miRNA is bound and cleaved by Dicer
to produce the mature miRNA molecule that can be integrated into the
RISC complex
19. 1. Microinjection: Microinjection, i.e. the direct injection of dsRNA into
the body of insects.
2. Soaking: dsRNA solution can inhibit gene expression, and its
effectiveness is comparable to the injection method in that it requires a
higher concentration of dsRNA.
3. Feeding of artificial diet: dsRNA feeding is the most attractive
primarily because it is convenient and easy to manipulate.
4. Developing transgenic insects: The using transgenic insects that carry
the dsRNA is that as it is inheritable, the expression can be stable and
continuous. The technique has been proposed to help either reduce
population through introduction of sterile insects or for population
replacement.
5. Virus-mediated uptake: Virus-mediated RNAi methods involve the
infection of the host with viruses carrying dsRNA formed during viral
replication and targeting the gene of interest in the host.
20.
21. The left panel: Feeding habits of the target insect is important in planning the (delivery) strategy.
The middle panel: Illustrates the dsRNA path/uptake by the microvilli of the columnar cells (MCC) in the insect
midgut, as well as its environmental and systemic properties.
The right panel: Shows the cellular siRNA mechanism of gene silencing.
24. F1 plants expressing a V-ATPase A dsRNA
are protected from Western Corn Rootworm
feeding damage.
(a) Map of the expression cassette.
(b) Mean root damage ratings for eight F1
populations, the parental inbred line
(negative control) and the corn rootworm–
protected Cry3Bb event MON863; NIS,
nodal injury score (Iowa State ranking
system).
(c) The plant on left is a non-transgenic
control with average root damage, whereas
the plant on the right shows the average
root protection seen when the transgene is
expressed.
Belgium Baum et al., (2007)
25. CYP6AE14 gene is highly
expressed in the midgut of the
H. armigera and its expression
correlates with larval growth
when gossypol is included in the
diet. When larvae are fed plant
material expressing double-
stranded RNA (dsRNA) specific
to CYP6AE14, levels of this
transcript in the midgut decrease
and larval growth is retarded.
Mao et al., (2007)China
26. Chemically synthesized siRNA
molecules were directly fed to
H. armigera larvae along with
the artificial diet. The siRNA
treatment resulted in specific
gene silencing of AChE and
consequently brought about
mortality, growth inhibition of
larvae, reduction in the pupal
weight, malformation and
drastically reduced fecundity as
compared to control larvae.
India Kumar et al., (2009)
siRNA-mediated inhibition of
larval growth in a dose-dependent
manner 1.control, 2. unrelated
siRNA, 3. 25 nM AChE siRNA,
4. 37.5 nM AChE-siRNA and 5.
50 nM AChE-siRNA.
27. M. persicae when fed on the transgenic plants for different time intervals under controlled
growth conditions resulted in a significant attenuation of the expression of MySP and a
commensurate decline in gut protease activity. Although the survivability of these aphids was
not affected, there was a noticeable decline in their fecundity resulting in a significant
reduction in parthenogenetic population.
India Bhatia et al., (2012)
28. Quantitative Real-time PCR was used to confirm silencing and detected that the transcript
levels of P. xylostella AChE2 (PxAChE2) were reduced by 90 % mortality compared to the
control group. Finally, effects of the siRNAs on treated plants of Brassica oleracea and
Brassica alboglabra were investigated with different siRNA doses. Our results showed that
Si-ace2_001 had no negative effects on plant morphology, color and growth of vein under
experimental conditions.
China Gong et al., (2013)
29. The results found that Planococcus citri showed lower fecundity and pronounced death of
crawlers after feeding on recombinant TMV-infected plants. Taken together, our data show
that actin, chitin synthase 1 and V-ATPase mRNAs are potential targets for RNAi
against P. citri, and that recombinant TMV is an effective tool for evaluating candidate
RNAi effectors in plants.
China Khan et al., (2013)
30. To manage the pest population of Spodoptera exigua knockdown of eight genes
including chitinase7, PGCP, chitinase1, ATPase, tubulin1, arf2, tubulin2 and
arf1 caused a significantly high level of mortality compared to the negative control.
Li et al., (2013)China
31. Last larval injection of the EYFP dsRNA results in a reduction of EYFP, expression or lack there of
in the wing primordial and eyes. (E-H) Penultimate larval RNAi for vg. (E) Wild-type
pupa. (F) vg RNAi pupa. The lack of wing structures is already visible at the pupal stage
(arrow). G) Wild-type adult. (H) vg RNAi adult. Wing related structures are completely
USA David et al., (2014)
32. RNA interference response against cathepsin-L gene in the pea aphid, Molting or gut
phenotypes specifically induced by injection
Phenotypes morphological external defects (on the right), is compared with a healthy
injected aphid (on the left). The arrows indicate the regions in the aphid body where the
defects are the most evident. S: sick aphid, m: melanization point.
France Panagiotis et al., (2014)
33. Citrus tristeza virus-based RNAi in citrus plants induces gene silencing in
Citrus Psyllid: Diaphorina citri
I. Images of D. citri adults developed from nymphs after exposure to Citrus tristeza virus wild
type (CTV) CTV-wt
II. Abnormal wing disc gene (tAwd) expressing CTV vector (CTV-tAwd )
USA Subhas et al., (2014)
34. Transgenic tobacco lines were developed for the expression of long dsRNA precursor to make siRNA and
knock down the V-ATPase mRNA in whitefly. Molecular analysis and insecticidal properties of the
transgenic plants established the formation of siRNA targeting the whitefly V-ATPase, in the leaves. The
transcript level of V-ATPase in whiteflies was reduced up to 62% after feeding on the transgenic plants.
India Thakur et al., (2014)
35. The dsRNA expression was driven by T7
RNA polymerase over expressed by an
inducer in the transformed E. coli. The
transformed bacteria gave a significant
oral toxicity to S. exigua larvae with a
significant reduction of the SeINT
expression. The larvae treated with the
transformed bacteria suffered tissue
damage in the midgut epithelium, which
exhibited a marked loss of cell-cell
contacts and underwent a remarkable
cell death. Moreover, these treated larvae
became significantly susceptible to a
Cry toxin.
South Korea Kim et al., (2015)
36. Chitinase (HaCHI) gene, critically
required for insect molting and
metamorphosis was selected as a
potential target. Continuous feeding on
leaves of RNAi lines drastically reduced
the target gene transcripts and
consequently, affected the overall growth
and survival of H. armigera. Various
developmental deformities were also
manifested in H. armigera larvae after
feeding on the leaves of RNAi lines.
These results demonstrated the role of
chitinase in insect development and
potential of HI-RNAi for effective
management of H. armigera.
Mamta et al., (2015)India
37. Tuta absoluta larvae that fed on leaves containing dsRNA of the target genes
(Vacuolar ATPase-A and Arginine kinase) showed 60% reduction in target
gene transcript accumulation, an increase in larval mortality and less leaf
damage.
Brazil Camargo et al., (2016)
38. Using RNA interference (RNAi) to down regulate whitefly genes by expressing their
homologous double stranded RNAs in plants has great potential for management of whiteflies
to reduce plant virus disease spread. Using a Tobacco rattle virus-derived plasmid for in planta
transient expression of double stranded RNA (dsRNA) homologous to the acetyl
cholinesterase (AChE) and ecdysone receptor (EcR) genes of B. tabaci, resulted in approx.
90 % significant adult whitefly mortality.
Malik et al., (2016)Pakistan
39. Image of pink bollworm larvae were injected with V-ATPase specific-dsRNA (dsRNA); “i” dead larvae and
“ii” retardation of larval development. Control larvae were injected with buffer showing normal
development of control larvae
Mohammed et al., (2016)Egypt
40. The potential of RNAi is Rhynchophorus
ferrugineus has been investigated through the silencing of
three different genes (α-amylase, V-ATPase, Ecdysone
receptor). Results show that RNAi mediated gene silencing
in R. ferrugineus varies from gene to gene, and that the
response is dose-dependent, with stronger effects when
dsRNA was administered by injection.
Italy Laudani et al. (2017)
41. Feeding double-stranded RNA effectively silenced TcCHIT transcription in Tetranychus
cinnabarinus. Meanwhile, TcCHIT silencing in larvae and adult resulted in an extremely high
mortality rate (53.3%), respectively, compared with those in the control group.
China Zhou et al. (2017)
42. Leaf disc feeding assays in two spotted spider mite revealed that knockdown in the
expression genes coding for proteins involved in the biosynthesis and action of juvenile
hormone (JH) and action of ecdysteroids [Methoprene-tolerant (Met), retinoid X receptor β,
farnesoic acid O-methyltransferase, and CREB-binding protein] caused 35–56% mortality.
China Yoon et al. (2018)
43. Chitin is a vital part of the insect
exoskeleton and peritrophic
membrane, synthesized by chitin
synthase enzymes (CHS). Results
revealed that the expression level of
CHS1 gene significantly decreased
after the oral delivery of dsRNA-
CHS1. The knockdown of CHS1 gene
caused up to 43%, 47%, and 59%
mortality in third-instar nymph of A.
gossypii after feeding of dsCHS1 for
24, 48, and 72 h, respectively, as
compared to the control.
China Ullah et al. (2019)
44. In this study, Scientists tested the expression of dsRNA in RNaseIII-deficient Escherichia coli HT115 which was then
fed to Plagiodera versicolora larvae, an insect pest of Salicaceae plants worldwide. By targeting six potential genes,
including (ACT), (SRP54), (HSC70), (SHI), (CACT), and (SNAP), we found that feeding bacteria-expressed dsRNA
successfully triggered the silencing of the five target genes tested and the suppression of ACT and SRP54 genes
caused significant mortality.
China Zhang et al. (2019)
45. Double-stranded RNA targeting these
two dsRNases, AAEL008858 and
AAEL004103 when fed to the larvae,
effectively reduced gut dsRNease
activity. When these dsRNases-
specific dsRNAs were co-delivered
with dsRNA targeting a cyan
fluorescent protein (CFP) reporter
gene, greater knockdown of CFP
fluorescence was observed. These
results suggest that inhibiting
dsRNases activity could enable the
implementation of RNAi-based
mosquito control methods.
Canada Giesbrecht et al. (2020)
46. The salivary gland transcript dsAkC002 and the gap gene hunchback
dsAkhbd, which resulted in aphid mortality when knocked down by injected
targeted siRNA or feeding-based dsRNA, respectively to control blue green
aphid.
Jacques et al. (2020)Australia
47. RNAi has great potential to contribute toward development of modern pest
management methods
RNAi, the sequence-specific suppression of gene expression, offers great
opportunities for insect science, especially to analyse gene function, to
manage pest populations
The success rate of RNAi could be enhanced by selecting a biologically
crucial target gene and refining dsRNA molecule and its delivery method.
Further, the development of transplastomic in order to express high amount of
dsRNA opens the new avenue for effective controlling of agricultural pests.
Supply of dsRNA solution through irrigation water, root drench, or trunk
injection would be a great strategy for pest control method and low
environmental risks.