Mutagenesis techniques like chemical mutagenesis using ethyl methane sulfonate (EMS) and physical mutagenesis using gamma irradiation and X-rays can be used to induce mutations in Jatropha curcas, an economically important plant. The document describes methods for mutagenesis in different tissues of J. curcas, including seeds, under in vitro and in vivo conditions. It also discusses approaches for detecting mutations, such as TILLING, and analyzing mutant populations to select plants with desirable traits for further breeding.
Bacterial transposons are mobile segments of DNA that can move within bacterial genomes. There are two main types: insertion sequences, which consist only of the DNA required for transposition; and composite transposons, which contain additional genes like antibiotic resistance genes flanked by insertion sequences. Transposons can move within genomes through replicative or conservative transposition and have played an important role in bacterial evolution and antibiotic resistance.
This document discusses DNA mutations and mutagenesis. It defines mutation as a heritable alteration in genetic material and describes the main types of mutations: substitutions, deletions, insertions, and frameshift mutations. It also discusses what causes mutations, including spontaneous mutations from replication errors and induced mutations from exposure to mutagens like chemicals, UV radiation, and ionizing radiation. Mutagens can cause changes in DNA structure like thymine dimers or breaks in the phosphodiester backbone. Learning objectives are to understand the definition of mutation, different types of mutations, and common mutagens.
Genetic manipulation of plant and animal cells have to be confirmed for further application. One such confirmatory method is the use of stains/dyes which produces fluorescence when the recombination is successful.
A transposable element (TE or transposon) is a DNA sequence that can change its position within a genome, sometimes creating or reversing mutations and altering the cell's genome size.
Transposition often results in duplication of the TE.
Barbara McClintock's discovery of these jumping genes earned her a Nobel Prize in 1983.
Transposable elements make up a large fraction of the genome and are responsible for much of the C-value of eukaryotic cells.
RNA splicing is the process by which introns, or non-coding sequences, are removed from pre-messenger RNA (pre-mRNA) to produce mature mRNA that can be translated into protein. Most genes contain introns that are removed by a spliceosome, a complex of RNA and proteins, leaving just the coding exons to form mRNA. Alternative splicing allows one gene to encode multiple proteins by selecting different combinations of exons. Errors in splicing can cause diseases if they result in truncated or abnormal proteins.
Mutations are changes in genetic material that can be harmful, beneficial, or neutral. There are two types of mutations: somatic mutations, which occur in body cells and are not passed to offspring, and germline mutations, which occur in sex cells and can be inherited. Germline mutations are more relevant for evolution and are generally what is meant by the term "mutation". Mutations can be caused by errors in DNA replication, environmental mutagens like radiation or chemicals, or due to changes in DNA base pairing. They result in changes at the DNA level like substitutions, insertions, deletions, and can have various effects at the protein and phenotypic levels.
The document discusses different types of point mutations that can occur in DNA. It defines point mutations as changes to one or a few base pairs, while chromosomal/segmental mutations involve changes to an entire chromosome or section of it. The main types of point mutations are substitutions, insertions, and deletions. Substitutions are further broken down into transitions and transversions. Point mutations can occur in coding or non-coding regions, with mutations in non-coding regions having no effect. Mutations in coding regions can be synonymous or non-synonymous, with synonymous mutations not changing the amino acid. Non-synonymous mutations include missense mutations, which change an amino acid, and nonsense mutations, which introduce a
Regulated gene expression is required for adaptation, differentiation, and development in organisms. In prokaryotes, genes involved in metabolic pathways are often arranged in operons, where a single regulatory region controls multiple structural genes. The lac operon in E. coli regulates genes for lactose metabolism. In the absence of lactose, the lac repressor binds the operator region and prevents transcription. When lactose is present, it binds the repressor and induces a conformational change that reduces its affinity for DNA, allowing transcription. This is an example of negative regulation through repression and derepression.
Bacterial transposons are mobile segments of DNA that can move within bacterial genomes. There are two main types: insertion sequences, which consist only of the DNA required for transposition; and composite transposons, which contain additional genes like antibiotic resistance genes flanked by insertion sequences. Transposons can move within genomes through replicative or conservative transposition and have played an important role in bacterial evolution and antibiotic resistance.
This document discusses DNA mutations and mutagenesis. It defines mutation as a heritable alteration in genetic material and describes the main types of mutations: substitutions, deletions, insertions, and frameshift mutations. It also discusses what causes mutations, including spontaneous mutations from replication errors and induced mutations from exposure to mutagens like chemicals, UV radiation, and ionizing radiation. Mutagens can cause changes in DNA structure like thymine dimers or breaks in the phosphodiester backbone. Learning objectives are to understand the definition of mutation, different types of mutations, and common mutagens.
Genetic manipulation of plant and animal cells have to be confirmed for further application. One such confirmatory method is the use of stains/dyes which produces fluorescence when the recombination is successful.
A transposable element (TE or transposon) is a DNA sequence that can change its position within a genome, sometimes creating or reversing mutations and altering the cell's genome size.
Transposition often results in duplication of the TE.
Barbara McClintock's discovery of these jumping genes earned her a Nobel Prize in 1983.
Transposable elements make up a large fraction of the genome and are responsible for much of the C-value of eukaryotic cells.
RNA splicing is the process by which introns, or non-coding sequences, are removed from pre-messenger RNA (pre-mRNA) to produce mature mRNA that can be translated into protein. Most genes contain introns that are removed by a spliceosome, a complex of RNA and proteins, leaving just the coding exons to form mRNA. Alternative splicing allows one gene to encode multiple proteins by selecting different combinations of exons. Errors in splicing can cause diseases if they result in truncated or abnormal proteins.
Mutations are changes in genetic material that can be harmful, beneficial, or neutral. There are two types of mutations: somatic mutations, which occur in body cells and are not passed to offspring, and germline mutations, which occur in sex cells and can be inherited. Germline mutations are more relevant for evolution and are generally what is meant by the term "mutation". Mutations can be caused by errors in DNA replication, environmental mutagens like radiation or chemicals, or due to changes in DNA base pairing. They result in changes at the DNA level like substitutions, insertions, deletions, and can have various effects at the protein and phenotypic levels.
The document discusses different types of point mutations that can occur in DNA. It defines point mutations as changes to one or a few base pairs, while chromosomal/segmental mutations involve changes to an entire chromosome or section of it. The main types of point mutations are substitutions, insertions, and deletions. Substitutions are further broken down into transitions and transversions. Point mutations can occur in coding or non-coding regions, with mutations in non-coding regions having no effect. Mutations in coding regions can be synonymous or non-synonymous, with synonymous mutations not changing the amino acid. Non-synonymous mutations include missense mutations, which change an amino acid, and nonsense mutations, which introduce a
Regulated gene expression is required for adaptation, differentiation, and development in organisms. In prokaryotes, genes involved in metabolic pathways are often arranged in operons, where a single regulatory region controls multiple structural genes. The lac operon in E. coli regulates genes for lactose metabolism. In the absence of lactose, the lac repressor binds the operator region and prevents transcription. When lactose is present, it binds the repressor and induces a conformational change that reduces its affinity for DNA, allowing transcription. This is an example of negative regulation through repression and derepression.
Mutagenesis is a process by which the genetic information of an organism is changed, resulting in a mutation. It may occur spontaneously in nature, or as a result of exposure to mutagens. It can also be
achieved experimentally using laboratory procedures.
In nature mutagenesis can lead to cancer and
various heritable diseases, but it is also a driving force of evolution.
The document discusses methods for directed mutagenesis in DNA. It describes how early methods involved random mutagenesis using physical and chemical mutagens. Modern techniques now allow directed mutagenesis through recombinant DNA methods, allowing specific mutations even at the single nucleotide level. Several directed mutagenesis methods are outlined, including oligonucleotide-mediated mutagenesis and PCR-based mutagenesis. Important discoveries in directed mutagenesis include methods developed for prokaryotes and eukaryotes in the 1980s, for which Mario Capecchi and Oliver Smithies received the Nobel Prize.
Site-directed mutagenesis is a technique used to introduce specific changes to the DNA sequence of a gene by altering the nucleotide sequence. It allows researchers to study the impact of mutations by changing individual bases, deleting bases, or inserting new bases. There are different methods of site-directed mutagenesis including oligonucleotide-based methods and PCR-based methods. Site-directed mutagenesis has applications in research, production of desired proteins, and development of engineered proteins for commercial uses like detergents.
This presentation provides an overview of What is a transposon,different types of transposons, their mechanism of action, examples for each type of transposons, changes caused due to insertion of transposon into the target gene and applications of Transposons. They are controlling factors in gene expression. Jumping genes is a special area of interest in Genetic research.
The document summarizes the mechanism of T-DNA transfer during Agrobacterium tumefaciens infection. It explains that T-DNA is a fragment of DNA transferred from the tumor-inducing (Ti) plasmid of A. tumefaciens into the host plant genome. The T-DNA is bordered by repeats and encodes genes that cause tumors in the plant. Virulence genes are expressed in response to plant signals and produce single-stranded T-DNA, which forms a complex with other proteins and is transported into the plant cell and integrated into the plant nuclear DNA, causing uncontrolled cell growth and tumor formation. The mechanism involves multiple virulence protein complexes and integration of T-DNA is directed by the
Mutations are changes in a DNA sequence that can result from errors in DNA copying, exposure to mutagens like radiation or chemicals, or infection by viruses. There are several types of mutations including chromosomal mutations like deletions, inversions, translocations, nondisjunction, and duplications as well as gene mutations like point mutations and frameshift mutations. Point mutations can be silent, missense, or nonsense while frameshift mutations occur due to insertions or deletions of nucleotides, changing the reading frame and resulting protein. Mutations can be caused spontaneously, induced by mutagens, or through inherited changes and can occur in somatic or germ-line cells with different effects on inheritance.
Transposon mutagenesis & site directed mutagenesisAnuKiruthika
This document provides information on transposon mutagenesis and site-directed mutagenesis. It defines transposons as "jumping genes" that can move locations in the genome and explains that transposon mutagenesis uses transposons to cause mutations by interrupting genes. Site-directed mutagenesis is described as an in vitro technique to introduce specific mutations into DNA using methods like conventional PCR, nested PCR, or inverse PCR. The document outlines several applications of these mutagenesis methods such as identifying virulence genes or screening for desired mutations.
post translational modifications of proteinAnandhan Ctry
Post-translational modifications (PTMs) are chemical modifications of proteins that occur after translation. PTMs play a key role in regulating protein function by modifying activity, localization, and interactions. The main types of PTMs discussed are phosphorylation, glycosylation, ubiquitination, S-nitrosylation, methylation, N-acetylation, lipidation, and proteolysis. These modifications are identified through techniques like mass spectrometry, HPLC, radioactive labeling, and gel electrophoresis. PTMs are important for processes like cell signaling, growth, and apoptosis.
Molecular basis of spontanceous mutation,induced mutation & physical and ...gohil sanjay bhagvanji
This document discusses different types of mutations, including spontaneous, induced, and those caused by physical and chemical mutagens. Spontaneous mutations occur naturally at a low rate due to errors in DNA replication. Induced mutations have a higher rate due to mutagens like radiation and chemicals. Physical mutagens include ionizing radiation like X-rays which can break DNA bases, and UV light which causes thymine dimers. Chemical mutagens are substances like nitrous acid and alkylating agents that directly damage DNA and induce mutations by changing bases or incorporating false bases. Temperature can also induce mutations by affecting DNA stability and reaction rates.
This document discusses the molecular mechanisms of spontaneous and induced mutations. It begins with an introduction and overview of types of mutations. It then describes spontaneous mutations that can occur due to DNA replication errors, spontaneous DNA lesions like depurination and deamination, and transposition. It also explains induced mutations caused by physical mutagens like radiation and heat, and chemical mutagens such as base analogs, alkylating agents, and intercalating agents. The document concludes with definitions of mutation rate and frequency.
The document discusses Agrobacterium rhizogenes, which causes hairy root disease in plants. It contains genes on Ri plasmids, including rol genes, that are transferred to plant cells and cause root proliferation. The T-DNA from the plasmid is integrated into the plant genome. Agrobacterium attaches to wounded plant cells, vir genes are activated by compounds from the plant, and the T-DNA and virulence genes work together to transfer T-DNA to the plant cell. Hairy roots can be grown in vitro for research on plant-pathogen interactions and production of compounds.
This document discusses transposable elements, which are discrete DNA sequences that can move to different locations within a genome. It covers the history of their discovery, mechanisms of transposition, classification into retrotransposons and DNA transposons, and examples found in bacteria. Specifically, it describes three types of bacterial transposable elements - insertion sequences, composite transposons, and non-composite transposons. The effects of transposable elements include gene inactivation, mutation, and their role in disease, but they can also help organisms adapt to stress and confer antibiotic resistance in bacteria.
A suppressor mutation counters the effects of an original mutation by restoring the wild-type phenotype. There are two main types of suppressor mutations: intragenic mutations occur within the same gene and restore function through alternate amino acid substitutions, while intergenic mutations occur elsewhere in the genome and restore function through interacting gene products. Suppressor mutations are useful for studying protein-protein interactions and dissecting biological pathways.
An overview of the Agrobacterium-mediated gene transfer process. Moreover, studied different kinds of Agrobacterium species are involved in this mechanism.
Agrobacterium is a rod-shaped, Gram-negative bacteria found mostly in the soil. It is a plant pathogen that is responsible for causing crown gall disease in them. This bacteria is also known as the natural genetic engineer because of it's the ability to integrate its plasmid Gene into the plant genome.
Agrobacterium tumefaciens transfer of their genetic material T-DNA of Ti-plasmid into the plant cell: A: Agrobacterium tumefaciens; B: Agrobacterium genome; C: Ti Plasmid : a: T-DNA , b: Vir genes , c: Replication origin , d: Opines catabolism genes; D: Plant cell
A Ti-Plasmid (tumor-inducing plasmid) is a ds, circular DNA that often, but not always. It's a piece of genetic equipment that transfers genetic material from bacterial cells means Agrobacterium tumefaciens into plant cells used to induce tumors in the plant. The Ti-plasmid is damage when Agrobacterium is grown above 28 °C. Such cured bacteria don't induce crown gall disease in the plant due to they are avirulent. The Ti-Plasmid are classified into two types on the basis of opine genes are present in T-DNA.
The Plasmid has 196 genes that code for 195 proteins. There is no one structural RNA. The plasmid is 206.479 nucleotides long. the GC content is 56% and 81% of the genetic material is coding genes.
The modification of this plasmid is a very important source in the production of transgenic plants.
The T-DNA must be cut out of the circular plasmid. A VirD1/D2 complex nicks the DNA at the left and right border sequences. The VirD2 protein is covalently attached to the 5' end. VirD2 contains a motif that leads to the nucleoprotein complex being targeted to the type IV secretion system (T4SS).
In the cytoplasm of the recipient cell, the T-DNA complex becomes coated with VirE2 proteins, which are exported through the T4SS independently from the T-DNA complex. Nuclear localization signals, or NLS, located on the VirE2 and VirD2 are recognized by the importin alpha protein, which then associates with importin beta and the nuclear pore complex to transfer the T-DNA into the nucleus. So that the T-DNA can integrate into the host genome.
We inoculate Agrobacterium containing our genes of interest, onto wounded plant tissue explants. The Agrobacterium then transfers the gene of interest into the DNA of the plant tissue.
This document provides information on various methods of gene transfer in plants, including Agrobacterium-mediated gene transfer and direct gene transfer methods. Direct methods rely on delivering large amounts of DNA to plant cells through techniques like particle bombardment, electroporation, and microinjection. Agrobacterium-mediated gene transfer utilizes the bacterium Agrobacterium, which transfers genes into plant genomes. The document discusses several direct and Agrobacterium-mediated methods in detail and provides advantages and limitations of each approach.
Transposons are DNA sequences that can change position within a genome. Barbara McClintock first discovered transposons in corn in the 1940s. There are two classes of transposons: class I (retrotransposons) move via an RNA intermediate, while class II (DNA transposons) move directly via a cut-and-paste mechanism. Transposons make up a large percentage of many genomes and can cause mutations when they insert into genes, which has implications for genetic disease and genome evolution.
This document provides an overview of mutation breeding. It discusses the historical development of mutation breeding, including key discoveries. It describes spontaneous and induced mutations and different types of mutations based on their effects. It also discusses mutagens, both physical (radiation) and chemical, and how they are used to induce mutations. The document outlines the general procedure for mutation breeding programs, including selecting plant materials, choosing mutagen doses, and screening mutated populations.
This document provides information on mutation breeding including definitions, types of mutations, mutagens, procedures for mutation breeding, applications, advantages, and limitations. It defines mutation as a sudden heritable change in a characteristic of an organism. It describes spontaneous and induced mutations and lists common mutagens like radiation and chemicals. The key steps in mutation breeding procedures are selection of crop variety, treatment with mutagen, handling of subsequent generations, and selection of desirable mutants. Applications include improving disease resistance and quantitative traits. However, limitations include the low frequency of beneficial mutations and difficulties associated with undesirable side effects and pleiotropic effects.
Mutagenesis is a process by which the genetic information of an organism is changed, resulting in a mutation. It may occur spontaneously in nature, or as a result of exposure to mutagens. It can also be
achieved experimentally using laboratory procedures.
In nature mutagenesis can lead to cancer and
various heritable diseases, but it is also a driving force of evolution.
The document discusses methods for directed mutagenesis in DNA. It describes how early methods involved random mutagenesis using physical and chemical mutagens. Modern techniques now allow directed mutagenesis through recombinant DNA methods, allowing specific mutations even at the single nucleotide level. Several directed mutagenesis methods are outlined, including oligonucleotide-mediated mutagenesis and PCR-based mutagenesis. Important discoveries in directed mutagenesis include methods developed for prokaryotes and eukaryotes in the 1980s, for which Mario Capecchi and Oliver Smithies received the Nobel Prize.
Site-directed mutagenesis is a technique used to introduce specific changes to the DNA sequence of a gene by altering the nucleotide sequence. It allows researchers to study the impact of mutations by changing individual bases, deleting bases, or inserting new bases. There are different methods of site-directed mutagenesis including oligonucleotide-based methods and PCR-based methods. Site-directed mutagenesis has applications in research, production of desired proteins, and development of engineered proteins for commercial uses like detergents.
This presentation provides an overview of What is a transposon,different types of transposons, their mechanism of action, examples for each type of transposons, changes caused due to insertion of transposon into the target gene and applications of Transposons. They are controlling factors in gene expression. Jumping genes is a special area of interest in Genetic research.
The document summarizes the mechanism of T-DNA transfer during Agrobacterium tumefaciens infection. It explains that T-DNA is a fragment of DNA transferred from the tumor-inducing (Ti) plasmid of A. tumefaciens into the host plant genome. The T-DNA is bordered by repeats and encodes genes that cause tumors in the plant. Virulence genes are expressed in response to plant signals and produce single-stranded T-DNA, which forms a complex with other proteins and is transported into the plant cell and integrated into the plant nuclear DNA, causing uncontrolled cell growth and tumor formation. The mechanism involves multiple virulence protein complexes and integration of T-DNA is directed by the
Mutations are changes in a DNA sequence that can result from errors in DNA copying, exposure to mutagens like radiation or chemicals, or infection by viruses. There are several types of mutations including chromosomal mutations like deletions, inversions, translocations, nondisjunction, and duplications as well as gene mutations like point mutations and frameshift mutations. Point mutations can be silent, missense, or nonsense while frameshift mutations occur due to insertions or deletions of nucleotides, changing the reading frame and resulting protein. Mutations can be caused spontaneously, induced by mutagens, or through inherited changes and can occur in somatic or germ-line cells with different effects on inheritance.
Transposon mutagenesis & site directed mutagenesisAnuKiruthika
This document provides information on transposon mutagenesis and site-directed mutagenesis. It defines transposons as "jumping genes" that can move locations in the genome and explains that transposon mutagenesis uses transposons to cause mutations by interrupting genes. Site-directed mutagenesis is described as an in vitro technique to introduce specific mutations into DNA using methods like conventional PCR, nested PCR, or inverse PCR. The document outlines several applications of these mutagenesis methods such as identifying virulence genes or screening for desired mutations.
post translational modifications of proteinAnandhan Ctry
Post-translational modifications (PTMs) are chemical modifications of proteins that occur after translation. PTMs play a key role in regulating protein function by modifying activity, localization, and interactions. The main types of PTMs discussed are phosphorylation, glycosylation, ubiquitination, S-nitrosylation, methylation, N-acetylation, lipidation, and proteolysis. These modifications are identified through techniques like mass spectrometry, HPLC, radioactive labeling, and gel electrophoresis. PTMs are important for processes like cell signaling, growth, and apoptosis.
Molecular basis of spontanceous mutation,induced mutation & physical and ...gohil sanjay bhagvanji
This document discusses different types of mutations, including spontaneous, induced, and those caused by physical and chemical mutagens. Spontaneous mutations occur naturally at a low rate due to errors in DNA replication. Induced mutations have a higher rate due to mutagens like radiation and chemicals. Physical mutagens include ionizing radiation like X-rays which can break DNA bases, and UV light which causes thymine dimers. Chemical mutagens are substances like nitrous acid and alkylating agents that directly damage DNA and induce mutations by changing bases or incorporating false bases. Temperature can also induce mutations by affecting DNA stability and reaction rates.
This document discusses the molecular mechanisms of spontaneous and induced mutations. It begins with an introduction and overview of types of mutations. It then describes spontaneous mutations that can occur due to DNA replication errors, spontaneous DNA lesions like depurination and deamination, and transposition. It also explains induced mutations caused by physical mutagens like radiation and heat, and chemical mutagens such as base analogs, alkylating agents, and intercalating agents. The document concludes with definitions of mutation rate and frequency.
The document discusses Agrobacterium rhizogenes, which causes hairy root disease in plants. It contains genes on Ri plasmids, including rol genes, that are transferred to plant cells and cause root proliferation. The T-DNA from the plasmid is integrated into the plant genome. Agrobacterium attaches to wounded plant cells, vir genes are activated by compounds from the plant, and the T-DNA and virulence genes work together to transfer T-DNA to the plant cell. Hairy roots can be grown in vitro for research on plant-pathogen interactions and production of compounds.
This document discusses transposable elements, which are discrete DNA sequences that can move to different locations within a genome. It covers the history of their discovery, mechanisms of transposition, classification into retrotransposons and DNA transposons, and examples found in bacteria. Specifically, it describes three types of bacterial transposable elements - insertion sequences, composite transposons, and non-composite transposons. The effects of transposable elements include gene inactivation, mutation, and their role in disease, but they can also help organisms adapt to stress and confer antibiotic resistance in bacteria.
A suppressor mutation counters the effects of an original mutation by restoring the wild-type phenotype. There are two main types of suppressor mutations: intragenic mutations occur within the same gene and restore function through alternate amino acid substitutions, while intergenic mutations occur elsewhere in the genome and restore function through interacting gene products. Suppressor mutations are useful for studying protein-protein interactions and dissecting biological pathways.
An overview of the Agrobacterium-mediated gene transfer process. Moreover, studied different kinds of Agrobacterium species are involved in this mechanism.
Agrobacterium is a rod-shaped, Gram-negative bacteria found mostly in the soil. It is a plant pathogen that is responsible for causing crown gall disease in them. This bacteria is also known as the natural genetic engineer because of it's the ability to integrate its plasmid Gene into the plant genome.
Agrobacterium tumefaciens transfer of their genetic material T-DNA of Ti-plasmid into the plant cell: A: Agrobacterium tumefaciens; B: Agrobacterium genome; C: Ti Plasmid : a: T-DNA , b: Vir genes , c: Replication origin , d: Opines catabolism genes; D: Plant cell
A Ti-Plasmid (tumor-inducing plasmid) is a ds, circular DNA that often, but not always. It's a piece of genetic equipment that transfers genetic material from bacterial cells means Agrobacterium tumefaciens into plant cells used to induce tumors in the plant. The Ti-plasmid is damage when Agrobacterium is grown above 28 °C. Such cured bacteria don't induce crown gall disease in the plant due to they are avirulent. The Ti-Plasmid are classified into two types on the basis of opine genes are present in T-DNA.
The Plasmid has 196 genes that code for 195 proteins. There is no one structural RNA. The plasmid is 206.479 nucleotides long. the GC content is 56% and 81% of the genetic material is coding genes.
The modification of this plasmid is a very important source in the production of transgenic plants.
The T-DNA must be cut out of the circular plasmid. A VirD1/D2 complex nicks the DNA at the left and right border sequences. The VirD2 protein is covalently attached to the 5' end. VirD2 contains a motif that leads to the nucleoprotein complex being targeted to the type IV secretion system (T4SS).
In the cytoplasm of the recipient cell, the T-DNA complex becomes coated with VirE2 proteins, which are exported through the T4SS independently from the T-DNA complex. Nuclear localization signals, or NLS, located on the VirE2 and VirD2 are recognized by the importin alpha protein, which then associates with importin beta and the nuclear pore complex to transfer the T-DNA into the nucleus. So that the T-DNA can integrate into the host genome.
We inoculate Agrobacterium containing our genes of interest, onto wounded plant tissue explants. The Agrobacterium then transfers the gene of interest into the DNA of the plant tissue.
This document provides information on various methods of gene transfer in plants, including Agrobacterium-mediated gene transfer and direct gene transfer methods. Direct methods rely on delivering large amounts of DNA to plant cells through techniques like particle bombardment, electroporation, and microinjection. Agrobacterium-mediated gene transfer utilizes the bacterium Agrobacterium, which transfers genes into plant genomes. The document discusses several direct and Agrobacterium-mediated methods in detail and provides advantages and limitations of each approach.
Transposons are DNA sequences that can change position within a genome. Barbara McClintock first discovered transposons in corn in the 1940s. There are two classes of transposons: class I (retrotransposons) move via an RNA intermediate, while class II (DNA transposons) move directly via a cut-and-paste mechanism. Transposons make up a large percentage of many genomes and can cause mutations when they insert into genes, which has implications for genetic disease and genome evolution.
This document provides an overview of mutation breeding. It discusses the historical development of mutation breeding, including key discoveries. It describes spontaneous and induced mutations and different types of mutations based on their effects. It also discusses mutagens, both physical (radiation) and chemical, and how they are used to induce mutations. The document outlines the general procedure for mutation breeding programs, including selecting plant materials, choosing mutagen doses, and screening mutated populations.
This document provides information on mutation breeding including definitions, types of mutations, mutagens, procedures for mutation breeding, applications, advantages, and limitations. It defines mutation as a sudden heritable change in a characteristic of an organism. It describes spontaneous and induced mutations and lists common mutagens like radiation and chemicals. The key steps in mutation breeding procedures are selection of crop variety, treatment with mutagen, handling of subsequent generations, and selection of desirable mutants. Applications include improving disease resistance and quantitative traits. However, limitations include the low frequency of beneficial mutations and difficulties associated with undesirable side effects and pleiotropic effects.
The document summarizes the history and process of plant mutagenesis. It discusses how mutation breeding was traced back to 300 BC in China and how the work of Lewis John Stadler in the 1920s-1930s laid the foundation for mutation breeding using X-rays. It also notes that almost 70% of durum wheat and over 400 rice varieties have been developed through mutation breeding programs using physical and chemical mutagens like radiation. The document then explains the key terms, types of mutagens used, factors influencing mutagenesis, types of mutations induced, and the general steps involved in mutation breeding programs.
Gene mutations – introduction – definition – a brief history – terminology –
classification of mutations – characteristic features of mutations – spontaneous
mutations and induced mutations
Gene mutations – artificial induction of mutations – physical and chemical
mutagens – molecular basis of mutations – detection of sex-linked lethals in
Drosophila by CLB technique – detection of mutations in plants – the importance of
mutation in plant breeding programmes –
This document discusses mutation breeding. It begins by defining mutation as a heritable change in DNA sequence. It then provides a historical account of mutation breeding, noting early discoveries in the late 19th/early 20th century. It describes the process of mutation breeding, including selecting plants to treat, common mutagens used, screening M1-M4 generations to select desirable mutants, and conditions under which mutation breeding is most successful for crop improvement.
This document discusses mutation breeding in plants. It begins by defining key terms like mutation, mutagen, and mutant. It then describes the history of mutation breeding, which began in the 1920s with experiments exposing plants to radiation. The document outlines different types of mutations and mutagens used, including physical mutagens like radiation and chemical mutagens. The breeding process is explained as inducing mutations, screening mutants for desirable traits, and releasing improved varieties. Advantages include developing new varieties quickly, while disadvantages include the unpredictability of mutations. The document concludes by listing achievements of mutation breeding programs in India.
Mutation breeding is a process of exposing plants or seeds to chemical or radiation to generate mutants with desirable traits. It has been used since the 1920s to develop over 3200 new crop varieties. There are two types of mutations - spontaneous and induced. Induced mutations are caused by physical mutagens like radiation or chemical mutagens like EMS. The process involves selecting plants with desired mutations, breeding them with other varieties, and screening offspring for traits like increased yield, drought tolerance, or disease resistance. While it can develop useful traits quickly, mutation breeding also has disadvantages like unpredictability and potential health risks from mutagens. Several research centers in India have used it to develop higher yielding varieties of crops like rice, barley, and ground
The document discusses different modern methods of plant breeding including mutation breeding, polyploidy breeding, and haploidy breeding. It provides details on mutation breeding including how mutagens like radiation and chemicals can induce mutations and the process of mutation breeding from selection of material to development of new varieties. It also describes polyploidy breeding which involves variations in chromosome number like polyploids having more than two sets of genomes. Finally, it mentions how haploids which have only one set of chromosomes can be used in plant breeding through techniques like haploid production and chromosome doubling.
1. Mutation breeding is a plant breeding technique that uses mutagens like radiation and chemicals to induce mutations and generate genetic variability.
2. Mutagens act by altering the DNA of plants through changes like transitions, transversions, and frameshifts at the molecular level.
3. The process of mutation breeding involves selecting plant material, treating it with mutagens, growing the subsequent generations to identify desirable mutants, and evaluating mutants through yield trials before release as new varieties.
Polyploidy, mutation and hybridization with reference to medicinal plantsSiddhartha Das
This document discusses genetics as applied to medicinal plants, including polyploidy, mutation, and hybridization. It provides background on genetics concepts like genes, DNA structure, mitosis, and meiosis. It then discusses types of mutations like point mutations and chromosomal mutations that can be spontaneous or induced through mutagens like radiation, chemicals, or abnormal environments. Polyploidy is described as having multiple chromosome sets and being induced by chemicals like colchicine, which can increase yield of compounds in some medicinal plants. Hybridization is the crossing of different species or varieties to produce hybrids with new combinations of traits.
Mutations,natural selection and speciationbhavnesthakur
Mutations, natural selection, and speciation were the topics covered. The key points discussed include:
1. Mutations are sudden, inheritable changes in genetic material that can be caused by factors like radiation, chemicals, or replication errors. They can be beneficial, harmful, or neutral.
2. Natural selection occurs when heritable traits influence the reproductive success of organisms, meaning mutations that increase fitness are more likely to be passed on.
3. Over time, accumulation of genetic differences through natural selection and mutations can lead to the emergence of new species in a process known as speciation.
Mutation breeding is a technique used to induce desirable mutations in plants for crop improvement. It involves treating seeds or other plant materials with physical or chemical mutagens to generate genetic variations. Useful mutant traits such as disease resistance, abiotic stress tolerance, and yield improvements have been identified in many crops including rice, wheat, barley through mutation breeding. Over 3,200 mutant varieties of more than 75 crops and 25 ornamental plants have been commercially released worldwide using this technique. Mutation breeding is an effective, low-cost method for developing new crop varieties with desirable traits.
This document summarizes research on chloroplast engineering for various applications. Chloroplasts naturally contain their own DNA and can be genetically engineered via homologous recombination. This allows for high levels of transgene expression without gene silencing effects. The document discusses how chloroplasts have been engineered for herbicide resistance, pathogen resistance, drought tolerance, and production of recombinant proteins. While chloroplast engineering holds promise, limitations include lack of expression in non-green cells and full genome sequence information for some species.
This document discusses mutation, including its definition, types, and causes. Some key points:
- H.J. Muller first demonstrated induced mutation using X-rays in 1927 and won the Nobel Prize in 1949 for his contributions to genetics research.
- Mutation is defined as a sudden heritable change in an organism's phenotype or nucleotide sequence not due to segregation or recombination.
- Mutations can be induced artificially using physical mutagens like radiation or chemical mutagens like alkylating agents.
- At the molecular level, point mutations involve changes in a gene's base sequence and can be substitutions, deletions, or additions of nucleotide bases.
Plant biotechnology with having refrence from glickbhaktisapte112004
Plant biotechnology can be used to genetically engineer plants for insect and disease resistance. Common methods include expressing genes from Bacillus thuringiensis (Bt) that code for insecticidal proteins or genes for plant proteins that inhibit insect growth. Other strategies prevent the development of Bt-resistant insects. Virus resistance has been achieved by expressing viral coat proteins or antiviral plant proteins. Fungus and bacteria resistance can be conferred by overexpressing plant defense genes or salicylic acid production. Transgenic plants now provide protection from major agricultural pathogens and pests.
This document provides a summary of a Master's seminar presentation on crop improvement through mutation breeding. It discusses the historical background of mutation breeding, types of mutations, mutagens used, and the process of mutation breeding. Some key points include:
- Hugo de Vries first coined the term "mutation" in 1900 and was an early pioneer in the field. Mutation breeding aims to induce beneficial mutations to develop improved crop varieties.
- Physical mutagens like radiation and chemical mutagens like EMS are commonly used to induce mutations. The presentation provides several examples of mutant crop varieties developed through mutation breeding programs.
- The process involves treating seeds or plant parts with mutagens, growing the M1 generation with proper
21. Mutation Breeding in crop improvement Naveen Kumar
Mutation breeding in crop improvement can utilize both spontaneous and induced mutations. Induced mutations are caused by physical mutagens like radiation (x-rays, gamma rays, UV light) or chemical mutagens. Mutation rates can vary between genes and induced mutations occur more frequently than spontaneous mutations. Mutation breeding is useful for crop improvement by generating genetic variation for selection of desirable traits.
1. Strain improvement techniques aim to develop microbial variants that have higher productivity and lower costs of metabolite production. This is achieved through methods like mutation, recombination, protoplast fusion, and gene technology.
2. Microorganisms have regulatory mechanisms that limit metabolite synthesis to their requirements. Developing high yield strains requires suppressing these mechanisms, such as feedback inhibition and feedback repression.
3. Common methods for strain improvement include physical and chemical mutagenesis to induce mutations, and genetic recombination through processes like transformation, transduction, and conjugation in bacteria.
Mutation breeding involves deliberately inducing mutations in plants through chemicals or radiation in order to generate mutants with desirable traits. Some key points about mutation breeding include:
- It began in the 1920s when Hermann Muller demonstrated the first artificial mutation by treating a plant with radiation. This led to the field of mutation breeding which uses induced rather than natural mutations.
- There are two main types - spontaneous mutations that arise naturally, and induced mutations caused artificially through chemicals or radiation.
- Techniques for inducing mutations include exposing seeds or plants to x-rays, gamma rays, chemicals like ethyleneimine, or other mutagens.
- Mutation breeding has been successful in developing crops with traits like
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Perhaps most importantly, Thermodynamics rapidly became a primary tool in the advance of applied science/engineering/technology, spanning micro-tech, to aerospace and cosmology. I can think of no better a story to illustrate the breadth of scientific methodologies and applications at their best.
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Phenomics assisted breeding in crop improvementIshaGoswami9
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change, and increasing global population, crop yield and quality need to be improved in a sustainable way over the coming decades. Genetic improvement by breeding is the best way to increase crop productivity. With the rapid progression of functional
genomics, an increasing number of crop genomes have been sequenced and dozens of genes influencing key agronomic traits have been identified. However, current genome sequence information has not been adequately exploited for understanding
the complex characteristics of multiple gene, owing to a lack of crop phenotypic data. Efficient, automatic, and accurate technologies and platforms that can capture phenotypic data that can
be linked to genomics information for crop improvement at all growth stages have become as important as genotyping. Thus,
high-throughput phenotyping has become the major bottleneck restricting crop breeding. Plant phenomics has been defined as the high-throughput, accurate acquisition and analysis of multi-dimensional phenotypes
during crop growing stages at the organism level, including the cell, tissue, organ, individual plant, plot, and field levels. With the rapid development of novel sensors, imaging technology,
and analysis methods, numerous infrastructure platforms have been developed for phenotyping.
Remote Sensing and Computational, Evolutionary, Supercomputing, and Intellige...University of Maribor
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The pygmy halfbeak Dermogenys colletei, is known for its viviparous nature, this presents an intriguing case of relatively low fecundity, raising questions about potential compensatory reproductive strategies employed by this species. Our study delves into the examination of fecundity and the Gonadosomatic Index (GSI) in the Pygmy Halfbeak, D. colletei (Meisner, 2001), an intriguing viviparous fish indigenous to Sarawak, Borneo. We hypothesize that the Pygmy halfbeak, D. colletei, may exhibit unique reproductive adaptations to offset its low fecundity, thus enhancing its survival and fitness. To address this, we conducted a comprehensive study utilizing 28 mature female specimens of D. colletei, carefully measuring fecundity and GSI to shed light on the reproductive adaptations of this species. Our findings reveal that D. colletei indeed exhibits low fecundity, with a mean of 16.76 ± 2.01, and a mean GSI of 12.83 ± 1.27, providing crucial insights into the reproductive mechanisms at play in this species. These results underscore the existence of unique reproductive strategies in D. colletei, enabling its adaptation and persistence in Borneo's diverse aquatic ecosystems, and call for further ecological research to elucidate these mechanisms. This study lends to a better understanding of viviparous fish in Borneo and contributes to the broader field of aquatic ecology, enhancing our knowledge of species adaptations to unique ecological challenges.
The use of Nauplii and metanauplii artemia in aquaculture (brine shrimp).pptxMAGOTI ERNEST
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Brine shrimp (Artemia spp.) are used in marine aquaculture worldwide. Annually, more than 2,000 metric tons of dry cysts are used for cultivation of fish, crustacean, and shellfish larva. Brine shrimp are important to aquaculture because newly hatched brine shrimp nauplii (larvae) provide a food source for many fish fry (Mozanzadeh et al., 2021). Culture and harvesting of brine shrimp eggs represents another aspect of the aquaculture industry. Nauplii and metanauplii of Artemia, commonly known as brine shrimp, play a crucial role in aquaculture due to their nutritional value and suitability as live feed for many aquatic species, particularly in larval stages (Sorgeloos & Roubach, 2021).
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Comparing the relative basicity of the nucleophile and the product is extremely helpful in determining how reversible the addition reaction is. Reactions with Grignards and hydrides are irreversible. Reactions with weak bases like halides and carboxylates generally don’t happen.
Electronic effects (inductive effects, electron donation) have a large impact on reactivity.
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Neutral nucleophiles can also add to carbonyls, although their additions are generally slower and more reversible. Acid catalysis is sometimes employed to increase the rate of addition.
2. ➢ Genetic variation is a source of
phenotypic diversity
▪ It is estimated that food production should be at least doubled by the year 2050 in order
to meet the needs of a continually growing population
➢ Primarily, simple selection of desirable
offspring was the first method of
breeding and this utilized the
occurrence of spontaneous
mutations
Introduction
➢ mutation induction has been an
important tool for crop breeding
since the release of the first mutant
variety of tobacco in the 1930s
4. Figure . Distribution of mutant crop varieties by continents
(Accessed on 15th July, 2015).
➢ The first commercial mutant
variety was produced in tobacco
in 1934
➢ Prior to 1995, reported 77
cultivars that were developed via
mutagenesis.
➢ In 1995, the number of
commercially released varieties
increased to 484.
▪ Some of the plants include fruit trees (e.g., apple, citrus, peach), ornamentals (e.g.,
chrysanthemum, dahlia, poinsettia), food crops (e.g., rice, barley, wheat, corn, pea), etc.
5. MUTATIONS
GENE MUTATION CHROMOSOMAL MUTATION GENOME MUTATION
At DNA level At protein level
- Transition
- Transversion
- Frame shift
- Silent
- Missense
- Non sense
- Neutral
Break in
Homologous
chromosome
Break in non
Homologous
chromosome
- Deletion
- Inversion
- Duplication
- Translocation
Aneuploidy
- Monosomic
- Trisomic
- Nullisomic
- Disomic
6. Mutagenesis is the process whereby sudden heritable changes occur in the
genetic information of an organism not caused by genetic segregation or genetic
recombination, but induced by chemical, physical or biological agents
MUTATIONS
Induced
mutations
Mutagens are those agents, with induces the mutations in a DNA molecules
MUTATIONS
Spontaneous
mutations
Random Targeted
About 35% of the 1440 commercial
varieties of roses, 25% of apple varieties
and 45% of potato seeds in the United
States
8. • H.j.Mullar first of all artificially induces the mutations
in flies
• L.j.stadler developed mutations in Barley and maize
Classified to:
(A). Ionizing Radiation
Particulate
Non-Particulate
(B). Non- Ionizing Radiation
Physical Mutagens
α - Ray
β – Ray
Fast neutrons
𝑪𝒐𝟔𝟎
𝑪𝒔𝟏𝟑𝟕
γ – Ray
X - Ray
Uv -Rays
9. ➢ The main Ionizing Radiations are
X-ray, α- ray, β-ray, γ-ray
➢ When these radiations react with
water, they produced highly active
free radicals (OH)
➢ These free radicals reacts with
DNA and the phosphodiester bond
of DNA resulted into mutagenic
effects
Physical Mutagens
X-ray
Wavelengths = ./01 - 10 nm
Penetration power = varies in
tissues from a few mm in the
long wavelength state to a few
cm in the short wavelength
state.
γ-ray
Release by decomposition
of isotopes such as 𝐶𝑜60
and 𝐶𝑠137
(half-life 3.5
years - 30 years)
Neutrons
produced in nuclear
reactors. The emission of
neutrons leads to the
release of high energy
and mutations.
Ionizing Radiation
10. ▪ UV rays don’t have such energy that they
cause ionization so its a non-ionizing radiation
▪ Mercury lamps have a wavelength of 250 to
290 nm and act as a source of ultraviolet light
in radiation.
▪ Nitrogenous bases absorbs UV lights and the
absorption is maximum at 260 nm.
▪ It causes the formation of Thymine dimer
(Pyrimedine dimer). If two thymine occur
together in one strand of DNA, UV light
causes fusion to form thymine dimer.
▪ At the site of thymine dimer confirmation of
DNA is changed, so rate of error during DNA
replication and transcription is high.
Physical Mutagens
Non- Ionizing Radiation
11. Typical symptoms of exposure to UV-B radiation on control leaves of cotton plants:
(a) No symptoms, (b) Initial chlorotic patches, and (c) Necrotic patches after
prolonged exposure. Adapted with permission from Prasad et al. (2003b)
Due to the long wavelength of ultraviolet light, its penetration into the tissue is limited
and it is used to induce mutations in cell cultures or protoplasts.
To do this, protoplasts are placed a few centimeters apart in unopened petri dishes under
a UV lamp. This reduces colony formation by 10 to 50 percent compared to non-mutant
protoplast culture.
Physical Mutagens
12. ❑ Rate of mutation a Amount of Radiation
The damage maybe
(a) Ss break
(b) Ds break
(c) Alteration in N sequence
✓ The ss damage may be
repaired in a cell but
others causes DELETION,
DUPLICATION, INVERSION
and TRANSLOCATION
✓ These radiations are used
for the treatment of
CANCER by giving the dose
of radiations at regular
interval
Physical Mutagens
14. Factors influencing the outcome of mutagenesis using physical mutagens
Oxygen >> The interplay between oxygen and ionising radiation continue from
irradiation to post-irradiation storage
Moisture content >> Seed moisture content is important.
Temperature >> preheating of cell lines has been shown to increase the incidence of
mutation events.
Other physical ionizing agents >> The presence of other unintended agents
(electromagnetic and ionizing radiation) increase mutation frequencies.
Dust and fibers >> Particles in the environment including dust and fibers (e.g. from
asbestos) increase significantly the incidence of mutagenicity of irradiation
Biological and infectious agents >> hormonal concentrations and Infectious agents
(both viral and bacterial) have been shown to elevate radiosensitivity.
Troubleshooting
15.
16. Chemical Mutagens
BASE ANALOGUES
- Maleic hydrazide
- Uridine derivatives
CHEMICALS
- Nitrous acid (HN𝐎𝟐)
- Hydroxyl amine (𝐇𝟐NO)
- Sodium azide (Na𝐍𝟑)
INTERCALATORS
- Ethidium bromide
- Proflavine
- Acridine orange
- daunorubicin
ALKYLATING AGENT
- Ethyl methyl sulphate
(EMS)
- Nitrogen mustards
- Mitomycin
- Methyl methane
sulfonate (MMS)
- Diethylsulfate (DES)
- Nitrosoguanidine (NG)
C . Auerbach – used the chemicals to induce the mutations
17. ❖ Base Analogues
➢ some chemicals are similar to N bases,
and these are called as base analogues.
➢ 5-Bermodioxyuridine (BrdU) and 5-
Bermoyuracil, are Analogs of thymine
and enter the DNA structure instead of
thymine.
➢ The frequency of mutations by these in
plants is low and therefore their use is
very limited.
In this way, 5-Bromo-Uracil can promote a change
of an AT base pair into a GC base pair
Chemical Mutagens
18. ➢ Some chemicals like Nitrogen,
Sulphur , mustard gas, MMS, EMS,
Nitrosoguanidine, NMU, NEV
➢ Due to these agents Methyl and
Ethyl groups transferred to N-
bases
➢ It resulted into changes in base
coupling potentials
➢ Transition and transversion type
mutation developed due to these
➢ Alkylating agents are compounds
with high reactivity
➢ EMS is commonly used for
mutations in plants ( ./1 – 3%)
➢ Urea nitroso is not stable in
alkaline solutions so it should be
PH= 5/6
Chemical Mutagens
❖ Alkylating Agents
19. ❖ Deamination Agents
➢ By the action of Nitrous Acid, amino
group is eliminated from The N base.
➢ Adenin…….. Hypoxanthine ( KETO)
Hypoxanthine ( KETO) binds with cytosin
Chemical Mutagens
21. ➢ Certain dyes like proflavine,
Acridine orange , ICR-170, ICR-191,
are strong mutagens
➢ These dyes inserted in between the
N bases and configuration of DNA
changed
➢ The interval between two purine
raised from 3.4A to 6.8A
Chemical Mutagens
❖ INTERCALATORS
22. ➢ The other important chemical
is Hydroxyl Amine
➢ Adding OH group to amino
group of cytosine
➢ It is responsible for GC…..AT
transition
Chemical Mutagens
23. Troubleshooting
▪ Factors that are critical to induced mutagenesis assays include the condition
of the mutagenic solution, the inherent characteristics of the target
tissue and the environment.
❖ Factors influencing the outcome of mutagenesis using chemical mutagens
Concentration of mutagen >>This is the most critical factor with the results of assays
depending to a great extent on the use of optimal concentrations of the mutagen.
Treatment volume >> The samples should be immersed completely in the mutagen
solution the volume of which must be large enough to prevent the existence of
concentration gradients during treatment. As a guide, a minimum of 0.5–1.0 ml of mutagen
solution per seed is suitable for most cereals
Treatment duration >>
The treatment should be long enough to permit hydration and infusion of the mutagen to
target tissue. The relevant seed characteristics that impact on this include seed size,
permeability of the seed coat and cell constituents. For EMS, this is 93 h at 20 ◦ C or 26 h at
30 ◦ C.
24. Troubleshooting
Temperature >> Related to hydrolysis is the temperature of the environment in which
the plant material is treated.
Presoaking of seeds >> This enhances the total uptake, the rate of uptake and the
distribution of mutagen within the target tissue. The duration of pre-soaking depends
primarily on the anatomy of the seed.For barley, a pre-soaking period of 16–20 h is
sufficient
pH >> The hydrogen ion concentration of the solution influences the hydrolysis of EMS.
by maintaining the pH of the EMS solution at the optimal vale of 7.0, injury to seeds and
explants is minimized.
Catalytic agents >> Certain metallic ions such as Cu2+ and Zn2+ have been implicated
in the enhancement of chromosomal aberrations induced by EMS. It is for this reason
that it is recommended to use deionized water to prepare the EMS emulsion.
Post-treatment handling The by-products of the incubation process (resulting from
hydrolysis) and residual active ingredients should be promptly washed off the incubated
target tissues after treatment.
25. Virus Transposon
Biological Agents
Bacteria
o Insertional Mutagenesis
➢ Identification of mutated genes
➢ Markers for chromosomal localization of mutated genes as
well as cloning of the original gene
➢ Selection of mutant plants based on their altered
phenotype from transgenic plants
26. • Whole plants, usually Seedlings, and in vitro Cultured cells. Nevertheless, the
most commonly used plant material is Seed.
The starting materials for the induction of mutations are vegetative cuttings, scions, or in
vitro cultured tissues like leaf and stem explants, anthers, callus, cell cultures,
microspores, ovules, protoplasts, etc.
➢ Gametes, usually inside the inflorescences, are also targeted for mutagenic
treatments through immersion of spikes, tassels, etc.
➢ it is noteworthy that the frequency and types of mutations are direct results of the
dosage and rate of exposure or administration of the mutagen rather than its type
Multiple forms of plant propagules, such as bulbs, tubers, corms and rhizomes and
more recently, the induction of mutations in vegetatively propagated plants is
becoming more efficient as scientists take advantage of totipotency using single cells
and other forms of in vitro cultured plant tissues.
Types of planting materials for performing Mutagenesis
29. Abstract
▪ Jatropha curcas is a semi-wild
▪ economically important shrub useful as a
source of biofuel or in soil reclamation
▪ it requires genetic improvement in order to
select the best genotypes for these
purposes.
the general methods for mutation induction
(chemical and physical mutagenesis) :
➢ ethyl methane sulfonate (EMS)
➢ gamma irradiation
➢ X-rays
induced mutants in different tissues of J.
curcas under in vitro and in vivo conditions.
30. ❖ Jatropha curcas is one of the most valuable
crops for its ability to produce seeds, which
contain 60–63 % of protein and 30–45 % of
toxic oil that renders the seedcake and oil
unsuitable for animal or human
consumption.
❖ The narrow genetic base in J. curcas hinders
efficient genetic improvement.
❖ In fact, the ultimate breeding objectives of
the J. curcas accessions are to reduce toxicity
and improve productivity under adverse
climatic conditions.
❖ To increase genetic diversity, mutagenesis
can be applied for plant improvement.
Introduction
31. Introduction
Ethyl methane sulfonate (EMS)
CH3SO2OC2H5
One of the most effective and
commonly used chemical mutagens
a monofunctional alkylating agent
base changes, breakage of the DNA
backbone, and mispairing
gamma rays, X-rays
Physical mutagens
low LET and produce energy in the form
of electromagnetic waves
most commonly used for mutation
breeding
deletions, point mutations, single- and
double-stranded brakes, and even
chromosome deletions
32. The Mutated populations (M1) are
generated
to reduce chimerism M2 or higher
populations are produced.
Entire mutant populations are
screened by either phenotypic
evaluation for selection of
phenotype of interest (forward
genetics) or by genotypic evaluation
for detection of novel allele in gene
of interest as well as study of gene
function (reverse genetics)
Schematic diagram of the basic
steps in physical and chemical
mutagenesis on different J.
curcas tissues
Methods
36. Further Analyses
❖ The second generation (and
higher) after chimera
dissolution of in vivo and in
vitro plants can be screened
for the selection of candidate
genes based on phenotypes
or genotypes.
37. ❖ Mutations can be detected with various direct and indirect methods such as:
➢ denaturing high-performance liquid chromatography (DHPLC),
➢ denaturing gradient gel electrophoresis (DGGE)
➢ temperature gradient capillary electrophoresis (TGCE)
➢ heteroduplex analysis (HD)
➢ single-stranded DNA conformation polymorphism (SSCP)
➢ chemical or enzymatic cleavage of mismatches (CECMs)
➢ Targeting Induced Local Lesions in Genome (TILLING)
➢ whole genome sequencing
➢ exome capture sequencing
➢ restriction-site-associated DNA (RAD) sequencing
➢ genotyping by sequencing (GBS)
Further Analyses
40. Conclusions
❖ For half a century, induced mutations have played an important role in plant breeding,
contributing to increased food production in both developed and developing economies.
Classical mutation breeding continues to be used for the benefit of communities in
parallel with application of modern genomic tools for mutation induction and discovery
in advanced laboratories.
❖ With 3211 registered mutant varieties in more than 170 different plant species, mutation
breeding has proven flexible, workable and ready to use on any crop if objectives and
selection methods are clearly identified. A range of mutagens are at our disposal to
induce mutations from the single nucleotide level to the genome level. Induced
mutations have not only played an unprecedented role in developing new crop cultivars
and novel products from existing crops, but also increasingly contribute to our
understanding of gene function and biochemical pathways. Along with newly emerged
‘omics’ techniques, induced mutations are contributing to the development of newly
emerging subject of systems biology.