This document provides an introduction to molecular biology. It discusses the key components of cells, including DNA, RNA, chromosomes, and organelles. The central dogma of molecular biology is explained as the flow of genetic information from DNA to RNA to protein. The structures and functions of both eukaryotic and prokaryotic cells are described. DNA replication, transcription, and protein synthesis are summarized as the basic processes by which genetic information is passed from parents to offspring.
DNA replication in prokaryotes occurs through a semi-conservative process where each daughter cell inherits one old and one new DNA strand. Replication begins at the origin of replication and proceeds bidirectionally. It involves three main stages - initiation, elongation, and termination. Initiation requires unwinding of the DNA duplex by helicase at the origin. Elongation is carried out by DNA polymerase III which synthesizes new DNA strands along the leading strand continuously and in short fragments along the lagging strand. Termination occurs when the replication forks from opposite directions meet.
The document summarizes key aspects of bacteriophage lambda. It describes that lambda can enter either the lytic cycle or lysogenic cycle. The lytic cycle involves a cascade of gene expression controlled by regulators that ultimately leads to bacterial lysis and phage particle release. The lysogenic cycle is maintained by the lambda repressor protein, which binds as a dimer to three operator sites and prevents expression of genes needed for the lytic cycle. The repressor uses a helix-turn-helix motif for specific DNA binding and binds cooperatively to operators to maintain lysogeny through an autoregulatory circuit.
It is a part of Ti Plasmid which takes part intransfer and integration of T-DNA into plant chromosome.
The vir sequence consist of 8 operons which take part in different functions associated with virulence of Ti Plasmid. These are vir H, vir A, vir B, vir G, vir C, vir D, vir E, & vir F. ( vir H & vir F present occasionally).
Gene manipulation involves externally arranging genes within an organism and is also known as genetic engineering. It was first used in agriculture to improve plant quality and was discovered in native Mexican corn in 2001. The process involves isolating DNA from an organism, introducing it into a vector or plasmid using restriction enzymes, and transforming it into a host cell. Restriction enzymes recognize specific DNA sequences and cleave the phosphodiester bonds between nucleotides at that site in viral, frog, or human DNA. Gene manipulation is concluded to include gene splicing, using recombinant DNA, forming monoclonal antibodies, and employing PCR thermocyclers, though it is not allowed for genetic manipulation in humans.
Dna supercoiling and role of topoisomerasesYashwanth B S
supercoiling is one of the important process to condenses the huge amount of DNA to fit inside the histone and its also plays a role during the replication ,transcription etc..,these activities is carried out by an enzyme called topoisomerases.
Agrobacterium tumefaciens is a soil bacterium that can transfer DNA fragments called T-DNA from its tumor-inducing (Ti) plasmid into the genome of plant cells. Scientists have harnessed this natural ability of A. tumefaciens by modifying its Ti plasmid to replace the tumor-causing genes with a gene of interest. This disarmed Ti plasmid, along with helper plasmids containing virulence genes, allows for the stable integration and expression of the new gene in plant cells. Common transformation methods using A. tumefaciens involve culturing plant explants like leaf disks with Agrobacteria containing the modified Ti plasmid, then regenerating transgenic plants from the transformed cells
Blotting techniques includes southren,northern,western and dot blottingbbmy
This document describes various blotting techniques used to detect specific DNA or RNA sequences, including Southern blotting, Northern blotting, Western blotting, and dot blotting. Southern blotting involves transferring DNA fragments separated by gel electrophoresis to a membrane and probing for specific sequences. Northern blotting is similar but uses RNA. Western blotting detects specific proteins. Dot blotting detects sequences in non-fractionated samples by directly applying samples to a membrane. These techniques allow for detection and analysis of genetic material.
This document discusses site-specific recombination, including the structures and mechanisms involved. It describes two classes of recombinases - tyrosine recombinases and serine recombinases. Tyrosine recombinases involve cleavage of DNA through formation of a protein-DNA bond using a tyrosine residue. Serine recombinases utilize a phosphoserine bond between DNA and a conserved serine residue. The document provides examples of applications for site-specific recombination such as tracking cell lineage, altering gene expression, and targeted gene knockout.
DNA replication in prokaryotes occurs through a semi-conservative process where each daughter cell inherits one old and one new DNA strand. Replication begins at the origin of replication and proceeds bidirectionally. It involves three main stages - initiation, elongation, and termination. Initiation requires unwinding of the DNA duplex by helicase at the origin. Elongation is carried out by DNA polymerase III which synthesizes new DNA strands along the leading strand continuously and in short fragments along the lagging strand. Termination occurs when the replication forks from opposite directions meet.
The document summarizes key aspects of bacteriophage lambda. It describes that lambda can enter either the lytic cycle or lysogenic cycle. The lytic cycle involves a cascade of gene expression controlled by regulators that ultimately leads to bacterial lysis and phage particle release. The lysogenic cycle is maintained by the lambda repressor protein, which binds as a dimer to three operator sites and prevents expression of genes needed for the lytic cycle. The repressor uses a helix-turn-helix motif for specific DNA binding and binds cooperatively to operators to maintain lysogeny through an autoregulatory circuit.
It is a part of Ti Plasmid which takes part intransfer and integration of T-DNA into plant chromosome.
The vir sequence consist of 8 operons which take part in different functions associated with virulence of Ti Plasmid. These are vir H, vir A, vir B, vir G, vir C, vir D, vir E, & vir F. ( vir H & vir F present occasionally).
Gene manipulation involves externally arranging genes within an organism and is also known as genetic engineering. It was first used in agriculture to improve plant quality and was discovered in native Mexican corn in 2001. The process involves isolating DNA from an organism, introducing it into a vector or plasmid using restriction enzymes, and transforming it into a host cell. Restriction enzymes recognize specific DNA sequences and cleave the phosphodiester bonds between nucleotides at that site in viral, frog, or human DNA. Gene manipulation is concluded to include gene splicing, using recombinant DNA, forming monoclonal antibodies, and employing PCR thermocyclers, though it is not allowed for genetic manipulation in humans.
Dna supercoiling and role of topoisomerasesYashwanth B S
supercoiling is one of the important process to condenses the huge amount of DNA to fit inside the histone and its also plays a role during the replication ,transcription etc..,these activities is carried out by an enzyme called topoisomerases.
Agrobacterium tumefaciens is a soil bacterium that can transfer DNA fragments called T-DNA from its tumor-inducing (Ti) plasmid into the genome of plant cells. Scientists have harnessed this natural ability of A. tumefaciens by modifying its Ti plasmid to replace the tumor-causing genes with a gene of interest. This disarmed Ti plasmid, along with helper plasmids containing virulence genes, allows for the stable integration and expression of the new gene in plant cells. Common transformation methods using A. tumefaciens involve culturing plant explants like leaf disks with Agrobacteria containing the modified Ti plasmid, then regenerating transgenic plants from the transformed cells
Blotting techniques includes southren,northern,western and dot blottingbbmy
This document describes various blotting techniques used to detect specific DNA or RNA sequences, including Southern blotting, Northern blotting, Western blotting, and dot blotting. Southern blotting involves transferring DNA fragments separated by gel electrophoresis to a membrane and probing for specific sequences. Northern blotting is similar but uses RNA. Western blotting detects specific proteins. Dot blotting detects sequences in non-fractionated samples by directly applying samples to a membrane. These techniques allow for detection and analysis of genetic material.
This document discusses site-specific recombination, including the structures and mechanisms involved. It describes two classes of recombinases - tyrosine recombinases and serine recombinases. Tyrosine recombinases involve cleavage of DNA through formation of a protein-DNA bond using a tyrosine residue. Serine recombinases utilize a phosphoserine bond between DNA and a conserved serine residue. The document provides examples of applications for site-specific recombination such as tracking cell lineage, altering gene expression, and targeted gene knockout.
DNA can be damaged through various means, including single base alterations, double base alterations, chain breaks, and cross-linking. Single base alterations include depurination, deamination, alkylation, base analogue incorporation, and mismatch bases. Double base alterations include pyrimidine dimers and purine dimers caused by UV radiation. Chain breaks include single and double stranded breaks caused by irradiation and free radicals. Cross-linking can occur between DNA and DNA or DNA and proteins due to UV radiation, ionizing radiation, and free radicals. Unrepaired damage can lead to mutations if incorrectly repaired during replication.
DNA replication in prokaryotes occurs through bidirectional replication from an origin of replication. It involves three main steps - initiation, elongation, and termination. During initiation, helicase unwinds the DNA at the origin of replication, forming a replication fork. In elongation, DNA polymerase extends RNA primers to synthesize new leading and lagging strands. The lagging strand is synthesized discontinuously in short Okazaki fragments. Termination occurs when replication is complete and the replicated circular DNA molecules are separated by topoisomerase II.
L10. enzymes used in genetic engineering i-1Rishabh Jain
This document discusses various enzymes that are used in genetic engineering and recombinant DNA technology. It describes DNA and RNA polymerases such as DNA polymerase I, Klenow fragment, T4 DNA polymerase, and reverse transcriptase. It also covers ligases, phosphatases, kinases, and nucleases including DNase I, and their functions, sources, and applications in techniques like cDNA synthesis, DNA labeling, amplification, and sequencing.
1. mRNA isolation is the process of extracting messenger RNA from biological samples. It is important for research and industry applications as mRNA provides insight into which genes are being expressed and translated into proteins.
2. Total RNA is first extracted using Trizol, which separates RNA, DNA and proteins. mRNA is then isolated from total RNA using biotin-labeled oligo dT probes that selectively bind to the poly-A tail of mRNA molecules.
3. The mRNA-probe complexes are immobilized on magnetic beads coated with streptavidin. This allows the mRNA to be separated and purified from other RNAs through magnetic separation washes. The purified mRNA can then be used in applications like RT-PCR and protein
RAPD (Random Amplification of Polymorphic DNA) is a PCR-based molecular marker technique that involves using short, arbitrary nucleotide primers to randomly amplify genomic DNA fragments. These fragments can then be analyzed as genetic markers. RAPD works by using a single short primer to amplify random DNA sequences from a complex template. Variations in priming sites between individuals result in presence or absence of bands that can be used to analyze genetic relationships. The technique is fast, inexpensive and does not require prior DNA sequence knowledge, but results can lack reproducibility between laboratories.
This document describes methods for purifying DNA from living cells. It discusses purification of total cellular DNA, plasmid DNA, and bacteriophage DNA. The basic protocol involves lysing cells to release DNA, then using enzymatic or chemical treatments to remove contaminating proteins, RNA, and other molecules. Specific techniques described include phenol/chloroform extraction, ion exchange chromatography, alkaline denaturation, and CsCl gradient centrifugation. The goal is to obtain purified DNA samples suitable for downstream applications like PCR and sequencing.
Single strand conformation polymorphismNivethitha T
Single-strand conformation polymorphism (SSCP) is a technique that detects variations in single-stranded DNA sequences. It involves PCR amplification of a target region, denaturing the PCR products to generate single strands, and separating the single strands on a non-denaturing gel based on differences in electrophoretic mobility caused by variations in nucleotide sequence. This allows sequences to be distinguished and variants detected without sequencing. SSCP is useful for discovering new polymorphisms and detecting mutations for diagnostic applications.
This document discusses various methods for ligating DNA fragments, including blunt end ligation, sticky end ligation using linkers or adaptors, and homopolymeric tailing. Blunt end ligation is less efficient than sticky end ligation. Linkers and adaptors are oligonucleotides used to create sticky ends for ligation, while homopolymeric tailing uses terminal transferase to add homopolymer tails to blunt ends before ligation. The goal is to efficiently join vector and insert DNA fragments for recombinant DNA construction.
Artificial chromosomes are synthetic chromosomes introduced into host cells to propagate and transfect DNA fragments larger than plasmids can hold. Yeast artificial chromosomes (YACs) specifically are engineered chromosomes derived from yeast DNA ligated into bacterial plasmids, allowing insertion of 100-1000kb DNA fragments. YACs contain elements for yeast and bacterial replication and selection, and are useful for cloning large genomic fragments like whole human genes for mapping the genome.
Rolling circle model and m13 bacteriophage replicationmicrobiology Notes
This document summarizes rolling circle replication and the replication of M13 bacteriophage. Rolling circle replication involves the nicking of one strand of circular DNA by an initiator protein. DNA polymerase then uses the unnicked strand as a template to synthesize multiple copies of the DNA in a continuous head-to-tail series. These linear copies can then be converted to circular DNA molecules through additional processing. Replication of M13 bacteriophage involves its single-stranded DNA entering an E. coli cell and being converted to double-stranded replicative form DNA. A phage protein then nicks the viral DNA to allow replication and production of progeny phage genomes and assembly of new viral particles.
Colony hybridization is a technique used to identify bacterial colonies containing a specific gene. It involves transferring bacterial colonies from a master plate onto a nitrocellulose filter to create replicas. The filter is then treated to lyse the bacterial cells and denature the DNA. A radioactive probe is used to hybridize to the target DNA sequence, and autoradiography identifies colonies containing the gene of interest. Colony hybridization allows efficient screening of bacterial colonies to isolate a specific DNA sequence.
This lecture is intended as an introduction to the fundamental concepts associated with plasmid DNA. Plasmids can be applied as vectors in Genetic Engineering for the production of recombinant proteins as well as the construction of genomic libraries for DNA sequencing projects.
This document provides an overview of genetic engineering techniques used to create transgenic plants, specifically focusing on Agrobacterium-mediated transformation. It discusses what transgenic plants are, genetic engineering methods like microprojectile bombardment and electroporation, and how Agrobacterium tumefaciens is used. A. tumefaciens causes crown gall disease by transferring T-DNA from its Ti plasmid into plant cells. The Ti plasmid and vir genes control this process. Researchers have developed Ti plasmid vectors to insert foreign genes between the T-DNA borders and transfer them to plant genomes, creating transgenic plants. Selectable marker genes like NPTII allow identification of transformed cells.
Genomic and cDNA libraries are constructed to isolate genes of interest from organisms. Genomic libraries contain total chromosomal DNA while cDNA libraries contain mRNA from specific cell types. DNA is digested and ligated into vectors to clone fragments. Libraries are screened using probes and PCR to identify clones containing genes of interest. cDNA libraries are useful for studying eukaryotic gene expression as they contain mRNA from specific cells. Thousands of clones may need to be screened to have high probability of isolating a particular gene fragment.
The document summarizes eukaryotic DNA replication. It discusses that DNA replication in eukaryotes is more complex than prokaryotes due to larger genome size and chromatin packaging. The key stages of eukaryotic replication are similar to prokaryotes, including origin of replication, formation of replication forks, semiconservative replication and synthesis of leading and lagging strands. However, eukaryotic replication involves additional proteins and is slower due to chromatin remodeling required to access DNA.
Probes are used for hybridization purposes. different types of probes can be used on the basis of what we want to hybridize. May be Radioactive or Non-Radioactive.
Mismatch Repair Mechanism Is One Of The Important DNA Repair Mechanism Which Recognizes And Replaces The Wrong Nucleotides. DNA Repair Is Important Since Its Failure Leads To Deadly Diseases Like Cancer. In This Presentation, You Will Learn About DNA Repair, Mismatch Repair, Proteins Involved In Prokaryotic And Eukaryotic MMR, Diagrams, Biological Importance Of MMR And References For Further Study.
Agrobacterium tumefaciens causes crown gall disease in plants by transferring oncogenic T-DNA from its Ti plasmid into the plant genome. The Ti plasmid contains three key regions - the T-DNA region containing tumor-inducing genes, the virulence region containing genes necessary for T-DNA transfer, and the opine synthesis region. In response to wound signals like acetosyringone released by injured plants, the virulence genes are activated and produce proteins that nick and transfer the single-stranded T-DNA into the plant cell, where it integrates randomly into the plant genome and expresses tumor-inducing genes causing uncontrolled growth.
The document discusses various methods of transfection in animals. Transfection is the process of introducing nucleic acids into eukaryotic cells. It describes viral transfection using bacteria like Agrobacterium tumefaciens and viruses. Non-viral methods include chemical transfection using calcium phosphate, liposomes, polyamines. Mechanical transfection employs microinjection or particle bombardment. Common chemical methods are calcium phosphate precipitation, polyplexes, and liposomes/lipoplexes. Viruses used are retroviruses, adenoviruses, adeno-associated viruses. Bacterial and viral vectors allow for integration into the host genome while chemical and mechanical are often transient.
The document provides an overview of key concepts in molecular biology including:
- DNA and RNA structure, including nucleotides, bases, sugars, and single vs double stranded forms.
- Key cellular components like genes, chromosomes, and genomes of prokaryotes and eukaryotes.
- Central processes like transcription, translation, and the central dogma.
- Differences between prokaryotic and eukaryotic cells, including bacterial vs human DNA organization and composition.
It also includes diagrams of DNA structure, the genetic code, and tRNA structure to illustrate these concepts. The document concludes with sample review questions.
The Indian Dental Academy is the Leader in continuing dental education , training dentists in all aspects of dentistry and
offering a wide range of dental certified courses in different formats.for more details please visit
www.indiandentalacademy.com
DNA can be damaged through various means, including single base alterations, double base alterations, chain breaks, and cross-linking. Single base alterations include depurination, deamination, alkylation, base analogue incorporation, and mismatch bases. Double base alterations include pyrimidine dimers and purine dimers caused by UV radiation. Chain breaks include single and double stranded breaks caused by irradiation and free radicals. Cross-linking can occur between DNA and DNA or DNA and proteins due to UV radiation, ionizing radiation, and free radicals. Unrepaired damage can lead to mutations if incorrectly repaired during replication.
DNA replication in prokaryotes occurs through bidirectional replication from an origin of replication. It involves three main steps - initiation, elongation, and termination. During initiation, helicase unwinds the DNA at the origin of replication, forming a replication fork. In elongation, DNA polymerase extends RNA primers to synthesize new leading and lagging strands. The lagging strand is synthesized discontinuously in short Okazaki fragments. Termination occurs when replication is complete and the replicated circular DNA molecules are separated by topoisomerase II.
L10. enzymes used in genetic engineering i-1Rishabh Jain
This document discusses various enzymes that are used in genetic engineering and recombinant DNA technology. It describes DNA and RNA polymerases such as DNA polymerase I, Klenow fragment, T4 DNA polymerase, and reverse transcriptase. It also covers ligases, phosphatases, kinases, and nucleases including DNase I, and their functions, sources, and applications in techniques like cDNA synthesis, DNA labeling, amplification, and sequencing.
1. mRNA isolation is the process of extracting messenger RNA from biological samples. It is important for research and industry applications as mRNA provides insight into which genes are being expressed and translated into proteins.
2. Total RNA is first extracted using Trizol, which separates RNA, DNA and proteins. mRNA is then isolated from total RNA using biotin-labeled oligo dT probes that selectively bind to the poly-A tail of mRNA molecules.
3. The mRNA-probe complexes are immobilized on magnetic beads coated with streptavidin. This allows the mRNA to be separated and purified from other RNAs through magnetic separation washes. The purified mRNA can then be used in applications like RT-PCR and protein
RAPD (Random Amplification of Polymorphic DNA) is a PCR-based molecular marker technique that involves using short, arbitrary nucleotide primers to randomly amplify genomic DNA fragments. These fragments can then be analyzed as genetic markers. RAPD works by using a single short primer to amplify random DNA sequences from a complex template. Variations in priming sites between individuals result in presence or absence of bands that can be used to analyze genetic relationships. The technique is fast, inexpensive and does not require prior DNA sequence knowledge, but results can lack reproducibility between laboratories.
This document describes methods for purifying DNA from living cells. It discusses purification of total cellular DNA, plasmid DNA, and bacteriophage DNA. The basic protocol involves lysing cells to release DNA, then using enzymatic or chemical treatments to remove contaminating proteins, RNA, and other molecules. Specific techniques described include phenol/chloroform extraction, ion exchange chromatography, alkaline denaturation, and CsCl gradient centrifugation. The goal is to obtain purified DNA samples suitable for downstream applications like PCR and sequencing.
Single strand conformation polymorphismNivethitha T
Single-strand conformation polymorphism (SSCP) is a technique that detects variations in single-stranded DNA sequences. It involves PCR amplification of a target region, denaturing the PCR products to generate single strands, and separating the single strands on a non-denaturing gel based on differences in electrophoretic mobility caused by variations in nucleotide sequence. This allows sequences to be distinguished and variants detected without sequencing. SSCP is useful for discovering new polymorphisms and detecting mutations for diagnostic applications.
This document discusses various methods for ligating DNA fragments, including blunt end ligation, sticky end ligation using linkers or adaptors, and homopolymeric tailing. Blunt end ligation is less efficient than sticky end ligation. Linkers and adaptors are oligonucleotides used to create sticky ends for ligation, while homopolymeric tailing uses terminal transferase to add homopolymer tails to blunt ends before ligation. The goal is to efficiently join vector and insert DNA fragments for recombinant DNA construction.
Artificial chromosomes are synthetic chromosomes introduced into host cells to propagate and transfect DNA fragments larger than plasmids can hold. Yeast artificial chromosomes (YACs) specifically are engineered chromosomes derived from yeast DNA ligated into bacterial plasmids, allowing insertion of 100-1000kb DNA fragments. YACs contain elements for yeast and bacterial replication and selection, and are useful for cloning large genomic fragments like whole human genes for mapping the genome.
Rolling circle model and m13 bacteriophage replicationmicrobiology Notes
This document summarizes rolling circle replication and the replication of M13 bacteriophage. Rolling circle replication involves the nicking of one strand of circular DNA by an initiator protein. DNA polymerase then uses the unnicked strand as a template to synthesize multiple copies of the DNA in a continuous head-to-tail series. These linear copies can then be converted to circular DNA molecules through additional processing. Replication of M13 bacteriophage involves its single-stranded DNA entering an E. coli cell and being converted to double-stranded replicative form DNA. A phage protein then nicks the viral DNA to allow replication and production of progeny phage genomes and assembly of new viral particles.
Colony hybridization is a technique used to identify bacterial colonies containing a specific gene. It involves transferring bacterial colonies from a master plate onto a nitrocellulose filter to create replicas. The filter is then treated to lyse the bacterial cells and denature the DNA. A radioactive probe is used to hybridize to the target DNA sequence, and autoradiography identifies colonies containing the gene of interest. Colony hybridization allows efficient screening of bacterial colonies to isolate a specific DNA sequence.
This lecture is intended as an introduction to the fundamental concepts associated with plasmid DNA. Plasmids can be applied as vectors in Genetic Engineering for the production of recombinant proteins as well as the construction of genomic libraries for DNA sequencing projects.
This document provides an overview of genetic engineering techniques used to create transgenic plants, specifically focusing on Agrobacterium-mediated transformation. It discusses what transgenic plants are, genetic engineering methods like microprojectile bombardment and electroporation, and how Agrobacterium tumefaciens is used. A. tumefaciens causes crown gall disease by transferring T-DNA from its Ti plasmid into plant cells. The Ti plasmid and vir genes control this process. Researchers have developed Ti plasmid vectors to insert foreign genes between the T-DNA borders and transfer them to plant genomes, creating transgenic plants. Selectable marker genes like NPTII allow identification of transformed cells.
Genomic and cDNA libraries are constructed to isolate genes of interest from organisms. Genomic libraries contain total chromosomal DNA while cDNA libraries contain mRNA from specific cell types. DNA is digested and ligated into vectors to clone fragments. Libraries are screened using probes and PCR to identify clones containing genes of interest. cDNA libraries are useful for studying eukaryotic gene expression as they contain mRNA from specific cells. Thousands of clones may need to be screened to have high probability of isolating a particular gene fragment.
The document summarizes eukaryotic DNA replication. It discusses that DNA replication in eukaryotes is more complex than prokaryotes due to larger genome size and chromatin packaging. The key stages of eukaryotic replication are similar to prokaryotes, including origin of replication, formation of replication forks, semiconservative replication and synthesis of leading and lagging strands. However, eukaryotic replication involves additional proteins and is slower due to chromatin remodeling required to access DNA.
Probes are used for hybridization purposes. different types of probes can be used on the basis of what we want to hybridize. May be Radioactive or Non-Radioactive.
Mismatch Repair Mechanism Is One Of The Important DNA Repair Mechanism Which Recognizes And Replaces The Wrong Nucleotides. DNA Repair Is Important Since Its Failure Leads To Deadly Diseases Like Cancer. In This Presentation, You Will Learn About DNA Repair, Mismatch Repair, Proteins Involved In Prokaryotic And Eukaryotic MMR, Diagrams, Biological Importance Of MMR And References For Further Study.
Agrobacterium tumefaciens causes crown gall disease in plants by transferring oncogenic T-DNA from its Ti plasmid into the plant genome. The Ti plasmid contains three key regions - the T-DNA region containing tumor-inducing genes, the virulence region containing genes necessary for T-DNA transfer, and the opine synthesis region. In response to wound signals like acetosyringone released by injured plants, the virulence genes are activated and produce proteins that nick and transfer the single-stranded T-DNA into the plant cell, where it integrates randomly into the plant genome and expresses tumor-inducing genes causing uncontrolled growth.
The document discusses various methods of transfection in animals. Transfection is the process of introducing nucleic acids into eukaryotic cells. It describes viral transfection using bacteria like Agrobacterium tumefaciens and viruses. Non-viral methods include chemical transfection using calcium phosphate, liposomes, polyamines. Mechanical transfection employs microinjection or particle bombardment. Common chemical methods are calcium phosphate precipitation, polyplexes, and liposomes/lipoplexes. Viruses used are retroviruses, adenoviruses, adeno-associated viruses. Bacterial and viral vectors allow for integration into the host genome while chemical and mechanical are often transient.
The document provides an overview of key concepts in molecular biology including:
- DNA and RNA structure, including nucleotides, bases, sugars, and single vs double stranded forms.
- Key cellular components like genes, chromosomes, and genomes of prokaryotes and eukaryotes.
- Central processes like transcription, translation, and the central dogma.
- Differences between prokaryotic and eukaryotic cells, including bacterial vs human DNA organization and composition.
It also includes diagrams of DNA structure, the genetic code, and tRNA structure to illustrate these concepts. The document concludes with sample review questions.
The Indian Dental Academy is the Leader in continuing dental education , training dentists in all aspects of dentistry and
offering a wide range of dental certified courses in different formats.for more details please visit
www.indiandentalacademy.com
A brief introduction to human genetics. Relevant to medical students i.e biochem, anatomy and physiology students.
It might be very short but it is also helpful.
- Frederic Miesher first isolated nucleic acid from salmon sperm in 1869, naming it nuclein.
- In 1920, Jones proved there are two types of nucleic acids: DNA and RNA.
- In 1953, Watson and Crick used data from Franklin and others to discover that DNA is a double helix with complementary base pairing between strands.
❖ The genome is the full complement of genetic information in a cell, contained in DNA or RNA. In eukaryotes, the genome is organized into multiple linear chromosomes within the cell nucleus. The human genome contains around 20,000-25,000 genes.
❖ Genes are regions of DNA that encode instructions. During transcription, genes are copied into mRNA, which is then translated into proteins. Eukaryotic genes can contain non-coding intron regions.
❖ Chromosomes are composed of DNA and protein. Eukaryotic cells normally contain two sets of chromosomes, making them diploid. During cell division, chromosomes condense and duplicate, with sister chromatids separating into new daughter cells
The document provides an overview of the structure and functions of the cell nucleus. It discusses how DNA is tightly packaged into chromosomes through winding around histone proteins to form nucleosomes and chromatin fibers. This compact packaging allows the 100 trillion meters of DNA in the human body to fit within cell nuclei. The nucleus contains DNA, which directs gene expression, DNA replication, and cell division. RNA carries DNA's genetic instructions out of the nucleus to direct protein synthesis. Key concepts covered include DNA and RNA structure, DNA replication, transcription, translation, and the central dogma of molecular biology.
Proteins are important macromolecules that have many functions in organisms, including serving as enzymes, hormones, antibodies, and performing structural and transport roles. They are composed of amino acids that are linked together by peptide bonds. There are over 20 different amino acids, with proteins containing thousands in long chains that fold into complex three-dimensional shapes determined by their primary, secondary, tertiary, and sometimes quaternary structures. This folding allows proteins to specifically bind other molecules and perform their diverse functions. Nucleic acids DNA and RNA also have important roles, with DNA containing the genetic code and RNA having roles in protein synthesis.
Protein synthesis involves transcription and translation. During transcription, DNA is copied into messenger RNA (mRNA) in the nucleus. The mRNA carries the genetic code from DNA to the cytoplasm for translation. Translation is the process by which the mRNA genetic code is used to produce a specific amino acid sequence or protein with the help of transfer RNA (tRNA) and ribosomes. The central dogma of molecular biology states that genetic information flows from DNA to RNA to protein.
In this paper, we briefly reviewed the numbers in life from a statistical genetic approach. The human genome comprises of 6 billion chemical bases of DNA. The DNA encodes 30,000 genes. It consists of two parts; the nuclear genome; which consists of 3,200,000,000 nucleotides of DNA, divided into 24 linear molecules, the shortest 50,000,000 nucleotides in length and the longest 260,000,000 nucleotides, each contained in a different chromosome and the mitochondrial genome; which contains approximately 16,600 base pairs encoding 37 genes. Most human cells have 46 chromosomes. However, the number of chromosomes in the nuclei of a person with Down syndrome is 47. The DNA of any two people on Earth is 99.6 percent identical, the 0.4 percent variation represents about 20 million base pairs. Almost all 98 percent of the human DNA is noncoding, while in bacteria, only 2% of the genetic material does not code for anything.
7_DNA organization in prokaryotes and eukaryotes.pptxAKHILRDONGA
DNA is the molecule that contains the genetic instructions used in the development and functioning of all known living organisms. In prokaryotes, DNA exists as a single circular chromosome located in the nucleoid region of the cell. Prokaryotic DNA is tightly packed using supercoiling, where the DNA winds further around itself. In eukaryotes, DNA is organized into linear chromosomes within the cell nucleus. Eukaryotic DNA is associated with histone proteins to form chromatin, which condenses into distinct chromosomes during cell division. The basic unit of hereditary information is the gene. Genes encode either functional products like proteins or regulatory elements that control gene expression.
The presentation includes about the basic knowledge of Deoxyribonucleic Acid or DNA. It involves the definition, structure, occurence, quantity, chemical composition, stability, variety, types, molecular weight, complementary of base pairs, absorbance, viscosity, ionic interactions, alternative forms and functions of DNA.
6 molecular basis of inheritance extraTeenTraining
This document provides definitions and explanations of key concepts related to molecular genetics and inheritance. It discusses DNA and RNA as the nucleic acids that carry genetic information. The central dogma of molecular biology involving DNA replication, transcription of DNA to RNA, and translation of RNA to protein is explained. Key terms like operon, exon, intron, and nucleosome are defined. DNA structure and packaging into chromatin and chromosomes is described. The experiments demonstrating that DNA is the genetic material like Griffith's transformation experiments and Avery, MacLeod, and McCarty's work are summarized. Semiconservative DNA replication and the Meselson-Stahl experiment supporting it are outlined. The process of transcription in prokaryotes and eukaryotes
DNA is the hereditary material found in humans and other organisms. It is a double-stranded molecule made up of nucleotides with four bases - adenine, guanine, cytosine, and thymine. Genes are sections of DNA that code for proteins or RNA chains and hold the information to build and maintain organisms. Vectors are DNA molecules used to transfer genes between cells. Common vectors include plasmids and viruses. The process of cloning involves isolating DNA from cells, cutting it into pieces using restriction enzymes, reassembling the pieces into a vector, and inserting the vector back into host cells.
DNA and RNA , Structure, Functions, Types, difference, Similarities, Protein ...AKSHAYMAGAR17
DNA contains the genetic instructions used in the development and functioning of all known living organisms. It is a long polymer made from repeating units called nucleotides, with each nucleotide containing a sugar, phosphate, and one of four nitrogenous bases. DNA exists as a double helix held together through base pairing between adenine and thymine and between cytosine and guanine. DNA stores and transmits genetic information from one generation of cells to the next through the process of replication. It also controls the production of proteins through transcription of DNA into RNA and the translation of RNA into proteins, which are essential for the structure, function, and regulation of the body.
The Indian Dental Academy is the Leader in continuing dental education , training dentists in all aspects of dentistry and
offering a wide range of dental certified courses in different formats.for more details please visit
www.indiandentalacademy.com
The Indian Dental Academy is the Leader in continuing dental education , training dentists in all aspects of dentistry and
offering a wide range of dental certified courses in different formats.for more details please visit
www.indiandentalacademy.com
Nucleic acids like DNA and RNA are long biopolymers composed of nucleotides. DNA stores genetic information in cells and is made up of deoxyribonucleotides arranged in a double helix structure. RNA is involved in protein synthesis and comes in several types including mRNA, tRNA, and rRNA. Nucleic acids have a primary structure defined by their linear sequence of nucleotides joined by phosphodiester bonds, and a secondary structure involving base pairing of nucleotides that gives them their characteristic helical shape.
Nucleic acids like DNA and RNA are long biopolymers composed of nucleotides. DNA stores genetic information in cells and is made up of deoxyribonucleotides arranged in a double helix structure. RNA is involved in protein synthesis and comes in several types including mRNA, tRNA, and rRNA. Nucleic acids have a primary structure defined by their linear sequence of nucleotides joined by phosphodiester bonds, and a secondary structure involving base pairing of nucleotides that gives them their characteristic helical shape.
Nucleic acids like DNA and RNA are long biopolymers composed of nucleotides. DNA stores genetic information in cells and is made up of deoxyribonucleotides arranged in a double helix structure. RNA is involved in protein synthesis and comes in several types including mRNA, tRNA, and rRNA. Nucleic acids have a primary structure defined by their linear sequence of nucleotides joined by phosphodiester bonds, and a secondary structure involving base pairing of nucleotides that gives them their characteristic helical shape.
How to Make a Field Mandatory in Odoo 17Celine George
In Odoo, making a field required can be done through both Python code and XML views. When you set the required attribute to True in Python code, it makes the field required across all views where it's used. Conversely, when you set the required attribute in XML views, it makes the field required only in the context of that particular view.
Walmart Business+ and Spark Good for Nonprofits.pdfTechSoup
"Learn about all the ways Walmart supports nonprofit organizations.
You will hear from Liz Willett, the Head of Nonprofits, and hear about what Walmart is doing to help nonprofits, including Walmart Business and Spark Good. Walmart Business+ is a new offer for nonprofits that offers discounts and also streamlines nonprofits order and expense tracking, saving time and money.
The webinar may also give some examples on how nonprofits can best leverage Walmart Business+.
The event will cover the following::
Walmart Business + (https://business.walmart.com/plus) is a new shopping experience for nonprofits, schools, and local business customers that connects an exclusive online shopping experience to stores. Benefits include free delivery and shipping, a 'Spend Analytics” feature, special discounts, deals and tax-exempt shopping.
Special TechSoup offer for a free 180 days membership, and up to $150 in discounts on eligible orders.
Spark Good (walmart.com/sparkgood) is a charitable platform that enables nonprofits to receive donations directly from customers and associates.
Answers about how you can do more with Walmart!"
Strategies for Effective Upskilling is a presentation by Chinwendu Peace in a Your Skill Boost Masterclass organisation by the Excellence Foundation for South Sudan on 08th and 09th June 2024 from 1 PM to 3 PM on each day.
How to Build a Module in Odoo 17 Using the Scaffold MethodCeline George
Odoo provides an option for creating a module by using a single line command. By using this command the user can make a whole structure of a module. It is very easy for a beginner to make a module. There is no need to make each file manually. This slide will show how to create a module using the scaffold method.
How to Manage Your Lost Opportunities in Odoo 17 CRMCeline George
Odoo 17 CRM allows us to track why we lose sales opportunities with "Lost Reasons." This helps analyze our sales process and identify areas for improvement. Here's how to configure lost reasons in Odoo 17 CRM
A review of the growth of the Israel Genealogy Research Association Database Collection for the last 12 months. Our collection is now passed the 3 million mark and still growing. See which archives have contributed the most. See the different types of records we have, and which years have had records added. You can also see what we have for the future.
it describes the bony anatomy including the femoral head , acetabulum, labrum . also discusses the capsule , ligaments . muscle that act on the hip joint and the range of motion are outlined. factors affecting hip joint stability and weight transmission through the joint are summarized.
ISO/IEC 27001, ISO/IEC 42001, and GDPR: Best Practices for Implementation and...PECB
Denis is a dynamic and results-driven Chief Information Officer (CIO) with a distinguished career spanning information systems analysis and technical project management. With a proven track record of spearheading the design and delivery of cutting-edge Information Management solutions, he has consistently elevated business operations, streamlined reporting functions, and maximized process efficiency.
Certified as an ISO/IEC 27001: Information Security Management Systems (ISMS) Lead Implementer, Data Protection Officer, and Cyber Risks Analyst, Denis brings a heightened focus on data security, privacy, and cyber resilience to every endeavor.
His expertise extends across a diverse spectrum of reporting, database, and web development applications, underpinned by an exceptional grasp of data storage and virtualization technologies. His proficiency in application testing, database administration, and data cleansing ensures seamless execution of complex projects.
What sets Denis apart is his comprehensive understanding of Business and Systems Analysis technologies, honed through involvement in all phases of the Software Development Lifecycle (SDLC). From meticulous requirements gathering to precise analysis, innovative design, rigorous development, thorough testing, and successful implementation, he has consistently delivered exceptional results.
Throughout his career, he has taken on multifaceted roles, from leading technical project management teams to owning solutions that drive operational excellence. His conscientious and proactive approach is unwavering, whether he is working independently or collaboratively within a team. His ability to connect with colleagues on a personal level underscores his commitment to fostering a harmonious and productive workplace environment.
Date: May 29, 2024
Tags: Information Security, ISO/IEC 27001, ISO/IEC 42001, Artificial Intelligence, GDPR
-------------------------------------------------------------------------------
Find out more about ISO training and certification services
Training: ISO/IEC 27001 Information Security Management System - EN | PECB
ISO/IEC 42001 Artificial Intelligence Management System - EN | PECB
General Data Protection Regulation (GDPR) - Training Courses - EN | PECB
Webinars: https://pecb.com/webinars
Article: https://pecb.com/article
-------------------------------------------------------------------------------
For more information about PECB:
Website: https://pecb.com/
LinkedIn: https://www.linkedin.com/company/pecb/
Facebook: https://www.facebook.com/PECBInternational/
Slideshare: http://www.slideshare.net/PECBCERTIFICATION
2. 2
Molecular Biology
Molecular biology; the study of biology at the
molecular level.
Molecular biology; the study of gene structure and
functions at the molecular level to understand the
molecular basis of hereditary, genetic variation, and the
expression patterns of genes.
The Molecular biology field overlaps with other
areas, particularly genetics and biochemistry.
3. 3
The Genome
The genome of an organism is the totality of genetic
information and is encoded in the DNA (or, for some
viruses, RNA).
commons.wikimedia.org
/
wiki/Image:Genome.jpg
4. 4
Genome Database
The database is organized in six major organism groups:
Eukaryotes, Bacteria, Archaea, Viruses, Viroids and Plasmids.
5. 5
All living things are grouped into three domain:
Eukaryotes;
Prokaryotes and
Archaea.
Three Domain of Life
6. 6
The Cell
The cell is the smallest
living unit, the basic
structural and functional
unit of all living things.
Some organisms, such as
most bacteria, are
unicellular (consist of a
single cell). Other
organisms, such as
humans, are multicellular.
7. 7
The Cell
Cells are stacked
together to make up
structures, tissues and
organs. Most cells have
got the same information
and resources and the
same basic material.
Cells can take many
shapes depending on
their function.
Function of cells
Secretion (Produce
enzymes).
Store sugars or fat.
Brain cells for memory
and intelligence.
Muscle cells to contract.
Skin cell to perform a
protective coating.
Defense, such as white
blood cells.
8. 8
Eukaryotic Cell
Eukaryotes are generally more advanced than
prokaryotes. There are many unicellular organisms which
are eukaryotic, but all cells in multicellular organisms are
eukaryotic.
Eukaryotic cells are found in animals; plants; fungi and
protists cell.
9. 9
Eukaryotic Cell
Cell with a true nucleus, where
the genetic material is
surrounded by a membrane;
Eukaryotic genome is more
complex than that of
prokaryotes and distributed
among multiple chromosomes;
Eukaryotic DNA is linear;
Eukaryotic DNA is
complexed with proteins called
"histones;
Numerous membrane-bound
organelles;
Complex internal structure;
Cell division by mitosis.
10. 10
Prokaryotic Cell
Unicellular organisms, found in
all environments. These
include bacteria and archaea.
Without a nucleus; no nuclear
membrane (genetic material
dispersed throughout
cytoplasm ;
No membrane-bound
organelles;
Cell contains only one circular
DNA molecule contained in the
cytoplasm;
DNA is naked (no histone);
Simple internal structure; and
Cell division by simple binary
fission.
12. 12
Eukaryotic Cell Cycle
Eukaryotic Cell Cycle :
defined as the sequence of
events that occurs during the
lifetime of a cell and is
traditionally divided into four
phases:
G1 = Growth and preparation
of the chromosomes for
replication
S = Synthesis of DNA
G2 = Preparation for mitosis
M = Mitosis
13. 13
Central Dogma of Molecular Biology
http://www.emc.maricopa.edu/faculty/farabee/BIOBK/BioBookPROTSYn.html
The flow of genetic information as follows:
14. 14
Deoxyribonucleic Acid (DNA)
Deoxyribonucleic Acid
(DNA), the genetic
material of all cellular
organisms and most
viruses, the gigantic
molecule which is used to
encode genetic
information for all life on
Earth.
17. 17
Thread like structure.
Located in the cell
nucleus.
The storage place for all
genetic information.
The number of
chromosomes varies from
one species to another.
The Chromosome
18. 18
In normal human cell
DNA contained in the
nucleus, arranged in 23
pairs of chromosomes ;
22 pairs of chromosomes
(autosomes) ; the 23
chromosome pair
determines the sex of
individual and is
composed of either two
(x) chromosomes
(female) or an (x) and (y)
chromosome (male).
The Chromosome
19. 19
The basic units of
inheritance; it is a
segment within a very
long strand of DNA with
specific instruction for the
production of one specific
protein. Genes located
on chromosome on it's
place or locus.
The Gene
20. 20
DNA and RNA are long
chain polymers of small
compound called
nucleotides. Each
nucleotide is composed
of a base; sugar (ribose
in RNA or deoxyribose in
DNA) and a phosphate
group. The phosphate
joins the sugars in a DNA
or RNA chain through
their 5` and 3` hydroxyl
group by phosphodiester
bonds.
General Structure of Nucleic Acid
21. 21
The structure of DNA was described by British
Scientists Watson and Crick as long double helix
shaped with its sugar phosphate backbone on the
outside and its bases on inside; the two strand of
helix run in opposite direction and are anti-parallel to
each other. The DNA double helix is stabilized by
hydrogen bonds between the bases.
This structure explains how genes engage in
replication, carrying information and acquiring
mutation.
The G+C content of a natural DNA can vary from 22-
73% and this can have a strong effect on the physical
properties of DNA, particularly its melting
temperature.
22. 22
There are four different types of nucleotides found in
DNA, differing only in the nitrogenous base: A is for
adenine; G is for guanine; C is for cytosine and T is for
thymine.
These bases are classified based on their chemical
structures into two groups: adenine and guanine are
double ringed structure termed purine , thymine and
cytosine are single ring structures termed pyrimidine.
The bases pair in a specific way: Adenine A with
thymine T (two hydrogen bonds) and guanine G with
cytosine C (three hydrogen bonds).
Within the structure of DNA, the number of thymine is
always equal to the number of adenine and the
number of cytosine is always equal to guanine.
In contrast to DNA; RNA is a single stranded, the
pyrimidine base uracil (U) replaces thymine and ribose
sugar replaces deoxyribose.
24. 24
Genomic DNA organization
Eukaryotic genes: DNA
molecules complexed
with other proteins
especially basic proteins
called histones, to form a
substance known as
chromatin. A human cell
contains about 2 meters
of DNA. DNA in body
could stretch to the sun
and back almost 100
times. So it is tightly
packed.
25. 25
Eukaryotic Chromatin
Eukaryotic chromatin
is folded in several ways.
The first order of folding
involves structures called
nucleosomes, which have
a core of histones,
around which the DNA
winds ( four pairs of
histones H2A, H2B,H3
and H4 in a wedge
shaped disc, around it
wrapped a stretch of 147
bp of DNA).
27. 27
DNA Replication
DNA Replication: The
DNA (all gene) duplication; the
transfer the genetic information
from a parent to a daughter cell ;
the DNA base sequence are
precisely copied.
Replication proceeds in a
semiconservative manner, each
strand of the DNA helix serves as
a template for the synthesis of
complementary DNA strands. This
lead to the formation of two
complete copies of the DNA
molecule, each consisting of one
strand derived from the parent
DNA molecule and one newly
synthesized complementary
strand.
28. 28
Mitochondrial DNA
Mitochondria is a membrane-
enclosed organelle found in most
eukaryotic cells.These organelles
range from 1–10 micrometers
(μm) in size.
Mitochondria generate most of
the cell's supply of adenosine
triphosphate (ATP).
Mitochondria are involved in a
range of other processes, such as
signaling, cellular differentiation,
cell death, as well as the control of
the cell cycle and cell growth.
Mitochondria have been
implicated in several human
diseases, including mental
disorders,cardiac dysfunction,[and
may play a role in the aging
process.
Mitochondria has its own DNA.
29. 29
Mitochondrial DNA
Mitochondrial DNA contains 37 genes, all of which
are essential for normal mitochondrial function. Thirteen
of these genes provide instructions for making enzymes
involved in oxidative phosphorylation.
Oxidative phosphorylation is a process that uses oxygen
and simple sugars to create adenosine triphosphate
(ATP), the cell's main energy source.
The remaining genes provide instructions for making
molecules called transfer RNAs (tRNAs) and ribosomal
RNAs (rRNAs).
Mitochondrial genes are among the estimated 20,000 to
25,000 total genes in the human genome.
30. 30
Function of The DNA
Deoxyribonucleic Acid (DNA), the gigantic
molecule which is used to encode genetic information
for all life on Earth.
The chemical basis of hereditary and genetic variation
are related to DNA.
DNA directs the synthesis of RNA which in turn
directs protein synthesis.
31. 31
The Genetic Code
The purine and pyrmidine bases of the DNA molecule
are the letters or alphabet of the genetic code. All
information contained in DNA represented by four letters:
A,T,C,G.
Three nucleotides of DNA (1st, 2nd and 3rd) form triplet
codons. A group of codons constitute the genetic code,
that can be translated into amino acid of proteins.
RNA Codon tRNA Amino Acids
32. 32
The Genetic Code
The sequence of codons
in the mRNA defines the
primary structure of the
final protein. Since there
are 64 possible codons,
most amino acids have
more than one possible
codon. Out of the 64
possible 3-base codons,
61 specify amino acids;
the other three are stop
signals (UAG, UAA, or
UGA).
33. 33
The RNA
Three major classes of RNA: messenger (mRNA),
transfer (tRNA) and ribosomal (rRNA). Minor classes
of RNA include small nuclear RNA ; small nucleolar
RNA;………..
34. 34
The RNA
- The concentration of
purine and pyrimidine
bases do not necessarily
equal one another in RNA
because RNA is single
stranded. However, the
single strand of RNA is
capable of folding back
on itself like a hairpin and
acquiring double strand
structure.
35. 35
Messenger RNA
mRNA molecules represent
transcripts of structural genes
that encode all the information
necessary for the synthesis of
a single type polypeptide of
protein.
mRNA; intermediate carrier
of genetic information; deliver
genetic information to the
cytoplasm where protein
synthesis take place.
The mRNA also contains
regions that are not translated:
in eukaryotes this includes the
5' untranslated region, 3'
untranslated region, 5' capand
poly-A tail.
36. 36
Transfer RNA(tRNA)
All tRNAs share a
common secondary
structure represented by
a coverleaf. They have
four-paired stems
defining three stem loops
(the D loop, anticodon
loop, and T loop) and the
acceptor stem to which
amino acids are added in
the charging step.
RNA molecules that carry
amino acids to the
growing polypeptide.
37. 37
Ribosomal RNA (rRNA)
Ribosomal RNA (rRNA) is the central component of
the ribosome, the function of the rRNA is to provide a
mechanism for decoding mRNA into amino acids and to
interact with the tRNAs during translation by providing
peptidyl transferase activity.
38. 38
Ribosomes
Ribosomes ; Factory for
protein synthesis; are
composed of ribosomal
RNA and ribosomal
proteins (known as a
Ribonucleoproteinor
RNP). They translate
messenger RNA (mRNA)
to build polypeptide
chains using amino acids
delivered by transfer RNA
(tRNA).
39. 39
Ribosomes
Eukaryotic ribosomes are larger. They consist of two
subunits; a 60S subunit holds (three rRNAs 5S, 5.8S,
28S and about 40 proteins) and a 40S subunit contains
(an18S rRNA and about 30 proteins) , which come
together to form an 80S particle compared with
prokaryotic 70S ribosome
40. 40
Most mRNA are
translated by more than
one ribosome at a time;
the result, a structure in
which many ribosomes
translate an mRNA in
tandem, is called a
polysomes.
Polysomes
41. 41
The Protein
Proteins are the basic building materials of a cell, made by cell
itself; the final product of most genes.
Proteins are chain like polymers of a few or many thousands of
amino acids. Amino acids are represented by codons, which are 3-
nucleotide RNA sequences. Amino acids joined together by peptide
bonds (polypeptide). Proteins can be composed of one or more
polypeptide chains.
Proteins have many functions: provide structure that help cells
integrity and shape (e.g. collagen in bone); serve as enzymes and
hormones; bind and carry substance and control of activities of
genes….
42. 42
Four levels of a protein's structure:
Primary structure: Formed by joining the amino acid
sequence into a polypeptide.
Secondary structure: Different conformation that can
be taken by the polypeptide: alpha helix and strands of
beta sheet.
Tertiary structure : Result from folding the secondary
structure components of the polypeptide into three-
dimensional configuration.
Quaternary structure : complex of several protein
molecules or polypeptide chains, usually called protein
subunits, which function as part of the larger assembly or
protein complex.
44. 44
Gene Expression
Gene expression process by which a gene product (an
RNA or polypeptide ) is made.
In transcription steps, RNA polymerase make a copy
of information in the gene (complementary RNA)
(mRNA) complementary to one strands of DNA.
In translation step, ribosomes read a messenger
RNA and make protein according to its instruction. Thus
any change in gene sequence may lead to change in the
protein product.
45. 45
Types of control in Eukaryotes
Transcriptional, prevent
transcription, prevent mRNA
from being synthesized.
Posttranscriptional,
control mRNA after it has been
produced.
Translational, prevent
translation; involve protein
factors needed for translation.
Posttranslational, after
the protein has been produced.
46. 46
Mutation
Mutation include both gross alteration of chromosome
and more subtle alteration to specific gene sequence.
Gross chromosomal aberrations include: large deletions;
addition and translocation (reciprocal and nonreciprocal).
Mutation in a gene's DNA sequence can alter the amino
acid sequence of the protein encoded by the gene. Point
mutations are the result of the substitution of a single base.
Frame-shift mutations occur when the reading frame of the
gene is shifted by addition or deletion of one or more bases.
47. 47
Mutation
Mutations can have harmful,
beneficial, neutral, or uncertain
effects on health and may be
inherited as autosomal
dominant, autosomal
recessive, or X-linked traits.
Mutations that cause serious
disability early in life are
usually rare because of their
adverse effect on life
expectancy and reproduction.
48. 48
Common Tools in Molecular Biology
Nucleic acid fractionation
Polymerase chain reaction
Probes, Hybridization
Vector, Molecular cloning
Nucleic acid enzymes
Microarray
DNA sequencing
Electrophoretic separation of nucleic acid
Detection of genes:
*DNA: Southern blotting; inSitu hybridization; FISH
Technique
*RNA: Northern blotting
*Protein: Western blotting, immunohistochemistry
49. 49
Human Genome Project
Goals
Identify all the approximately 20,000-25,000 genes in
human DNA,
Determine the sequences of the 3 billion chemical base
pairs that make up human DNA, store this information in
databases,
Improve tools for data analysis,
transfer related technologies to the private sector, and
Address the ethical, legal, and social issues (ELSI) that may
arise from the project.
50. 50
Molecular Biology : Uses
Various methods in molecular biology diagnose the
different human diseases; diagnosis of an infectious
agent, in malignancy, the presence of the genetic
disease and in transplantation, paternity and forensic
analysis.
The Most Recent Applied Technologies
Genetic engineering
DNA finger-printing in the social and forensic science.
Pre and postnatal diagnosis of inherited diseases.
Gene therapy.
Drug Design.
51. 51
Molecular biology is
facilitating research in
many field including
biochemistry,
microbiology,
immunology and
genetics,…………………
…
Molecular biology
allows the laboratory to
be predictive in nature,
it gives information that
the patients may be at
risk for disease (future).
52. 52
Glossary
Alleles are forms of the same gene with small differences in their sequence of DNA bases.
Exon (Coding DNA): A gene sequence contains protein coding information.
Introns (intervening sequence) (A noncoding DNA sequence ): Intervening stretches of DNA that separate exons.
Primary transcript: The initial production of gene transcription in the nucleus; an RNA containing copies of all exons and introns.
RNA gene or non-coding RNA gene: RNA molecule that is not translated into a protein. Noncoding RNA genes produce
transcripts that exert their function without ever producing proteins. Non-coding RNA genes include transfer RNA (tRNA) and
ribosomal RNA (rRNA), small RNAs such as snoRNAs, microRNAs, siRNAsand piRNAs and lastly long ncRNAs.
Enhancers and silencers: are DNA elements that stimulate or depress the transcription of associated genes; they rely on tissue specific
binding proteins for their activities; sometimes a DNA elements can act either as an enhancer or silencer depending on what is bound to it.
Activators: Additional gene-specific transcription factors that can bind to enhancer and help in transcription activation.
Open reading frame (ORF) : A reading frame that is uninterrupted by translation stop codon (reading frame that contains a start codonand
the subsequent translated region, but no stop codon).
Directionality: in molecular biology, refers to the end-to-end chemical orientation of a single strand of nucleic acid. The chemical convention
of naming carbon atoms in the nucleotide sugar-ring numerically gives rise to a 5' end and a 3' end ( "five prime end" and "three prime end"). The
relative positions of structures along a strand of nucleic acid, including genes, transcription factors, and polymerases are usually noted as being
either upstream (towards the 5' end) or downstream (towards the 3' end).
3' flanking region: Present adjacent to 3' end of the gene; often contain sequences which affect the formation of the 3` end of the message
and may contain enhancers or protein binding sites.
5' flanking region: A region adjacent to 5' end of the gene. It is not transcribed into RNA; it contains the promoter. May contain enhancers or
other protein binding sites.
3' untranslated region: The three prime untranslated region (3' UTR) is a particular section of messenger RNA (mRNA). It follows the
coding region. It is a region of the DNA which is transcribed into mRNA and becomes the 3' end or the message, Several regulatory sequences
are found in the 3' UTR. The 3' untranslated region may affect the translation efficiency of the mRNA or the stability of the mRNA. It also has
sequences which are required for the addition of the poly(A) tail to the message (including one known as the "hexanucleotide", AAUAAA).
5' untranslated region: The five prime untranslated region (5' UTR), also known as the leader sequence, is a particular section of messenger
RNA (mRNA) and the DNA that codes for it. It is a region of a gene which is transcribed into mRNA. It starts at the site (where transcription
begins) and ends just before the start codon (usually AUG) of the coding region. It usually contains a ribosome binding site (RBS), in bacteria also
known as the Shine Dalgarno sequence (AGGAGGU). In prokaryotic mRNA the 5' UTR is normally short. Some viruses and cellular genes have
unusual long structured 5' UTRs which may have roles in gene expression. Several regulatory sequences may be found in the 5' UTR.
Reverse Transcription: Some viruses (such as HIV, the cause of AIDS), have the ability to transcribe RNA into DNA.
53. 53
References & Online Further Reading
Robert F. Weaver. Molecular Biology. Fourth Edition. Page 600. McGraw-Hill International Edition. ISBN 978-0-07-110216-2
Innis,David H. Gelfand,John J. Sninsky PCR Applications: Protocols for Functional Genomics: ISBN:0123721865
Daniel H. Farkas. DNA Simplified: The Hitchhiker's Guide to DNA. Washington, DC: AACC Press, 1996, ISBN 0-915274-
84-1.
William B. Coleman,Gregory J. Tsongalis: Molecular Diagnostics: For the Clinical Laboratorian: ISBN 1588293564...
Robert F. Mueller,Ian D. Young. Emery's Elements of Medical Genetics: ISBN. 044307125X
Daniel P. Stites,Abba T. Terr. Basic Human Immunology: ISBN. 0838505430
Bruce Alberts, Alexander Johnson, Julian Lewis, Martin Raff, Keith Roberts, and Peter Walter. Molecular Biology
of the cell. ISBN. 9780815341055
http://www.pubmedcentral.nih.gov/
http://www.biomedcentral.com/1471-2105/2/8/abstract. Elena Rivas and Sean R Eddy Noncoding RNA gene
detection using comparative sequence analysis
BMC Bioinformatics 2001, 2:8doi:10.1186/1471-2105-2-8
www.medscape.com
http://www.medterms.com/script/main/art.asp?articlekey=4026
www.emedicine.com
www.ebi.ac.uk/2can good introduction to bioinformatics and molecular biology
http://www.genomicglossaries.com/
http://www.gene.ucl.ac.uk/nomenclature/guidelines.html defines the nomenclature for human genes
http://www.accessexcellence.org
http://users.rcn.com/jkimball.ma.ultranet/BiologyPages/C/Codons.html
http://www.web-books.com/MoBio/
http://www.expasy.org
http://www.emc.maricopa.edu/faculty/farabee/BIOBK/BioBookPROTSYn.html
Cell & Molecular Biology online: http://www.cellbio.com/recommend.html
http://www.ornl.gov/sci/techresources/Human_Genome/glossary/glossary.shtml%20
http://www.genome.gov/10000715
http://www.ncbi.nlm.nih.gov/About/primer/mapping.html
http://www.lilly.com/research/discovering/targets.html
http://www.informatics.jax.org/expression.shtml
www.wikipdia.com
http://www.biology.arizona.edu/cell_bio/tutorials/pev/page2.html
http://www.genome.ou.edu/protocol_book/protocol_index.html