DNA profiling is a technique used by scientists to distinguish between individuals using DNA samples. It was invented in 1985 by Alec Jeffreys at the University of Leicester. The process involves breaking down cells to extract DNA, cutting the DNA into fragments using restriction enzymes, separating the fragments by size using gel electrophoresis, and analyzing the pattern of fragments. DNA profiling is used to solve crimes by comparing crime scene DNA to suspects' DNA, and to solve medical problems like determining paternity. Famous cases that used DNA evidence include O.J. Simpson's murder trial and proving Steve Bing was the father of Elizabeth Hurley's child.
El documento describe varios conceptos clave relacionados con la expresión génica en procariotas y eucariotas. En procariotas, un operón es un conjunto de genes estructurales que se transcriben como una unidad y están regulados por una secuencia operadora adyacente. Los factores de transcripción regulan la expresión génica uniéndose a promotores y operadores. En eucariotas, la expresión génica está regulada a niveles transcripcionales y pos-transcripcionales, incluyendo modificaciones epigenéticas y proces
1. Plant tissue culture uses techniques to grow plant cells, tissues, or organs under sterile conditions on a nutrient culture medium. The type of media used depends on the plant species and material being cultured.
2. Common media include White's for root culture, MS for organogenesis and regeneration, B5 for cell suspension and callus culture, and N6 for cereal anther culture.
3. Media contains inorganic nutrients, carbon and energy sources, organic supplements like vitamins and amino acids, plant growth hormones, solidifying agents, and is sterilized before use.
The document describes the central dogma of molecular biology, which is the flow of genetic information from DNA to RNA to proteins. It covers DNA replication, transcription, translation, and how mutations can occur during these processes. DNA replication is semi-conservative and produces two identical DNA molecules from one original. Transcription produces mRNA from DNA, and translation uses mRNA to produce proteins according to the genetic code. Mutations can occur during replication, transcription or translation and result in changes to the amino acid sequence or reading frame of proteins.
Este documento describe la estructura y función de los ácidos nucleicos ADN y ARN. Los ácidos nucleicos son polímeros formados por la repetición de nucleótidos unidos mediante enlaces fosfodiéster. El ADN almacena y transmite la información genética de forma hereditaria a través de generaciones. El ARN tiene diversas funciones como dirigir la síntesis de proteínas y regular la expresión génica. Tanto el ADN como el ARN están formados por cadenas de nucleótidos compuestos por azúcares, bases
slide 2 central dogma
slide 3 key molecules used in translation
slide 4,5,6,7 all the key molcules with detail explanation
slide 8 phases of translation
slide 9 initiation and its process
slide 10 explanation initiation
slide 11 elongation and translocation
slide 12 process and steps of elongation and tRNA recharge in detail
slide 13 termination and its stages.
slide 14 diagrammatic representation of all the steps of termination with discrption
slide 15 thank you
This document provides an overview of DNA typing techniques used in forensics. It discusses the history of DNA analysis, beginning with its discovery and use in DNA fingerprinting in 1985. It also describes different DNA typing methods, including Restriction Fragment Length Polymorphism (RFLP), Polymerase Chain Reaction (PCR), and Short Tandem Repeats (STRs). Finally, it outlines the sample processing steps involving biology, technology, and genetics used to extract, amplify, separate, detect, and compare DNA from crime scene evidence and suspects.
DNA profiling is a technique used by scientists to distinguish between individuals using DNA samples. It was invented in 1985 by Alec Jeffreys at the University of Leicester. The process involves breaking down cells to extract DNA, cutting the DNA into fragments using restriction enzymes, separating the fragments by size using gel electrophoresis, and analyzing the pattern of fragments. DNA profiling is used to solve crimes by comparing crime scene DNA to suspects' DNA, and to solve medical problems like determining paternity. Famous cases that used DNA evidence include O.J. Simpson's murder trial and proving Steve Bing was the father of Elizabeth Hurley's child.
El documento describe varios conceptos clave relacionados con la expresión génica en procariotas y eucariotas. En procariotas, un operón es un conjunto de genes estructurales que se transcriben como una unidad y están regulados por una secuencia operadora adyacente. Los factores de transcripción regulan la expresión génica uniéndose a promotores y operadores. En eucariotas, la expresión génica está regulada a niveles transcripcionales y pos-transcripcionales, incluyendo modificaciones epigenéticas y proces
1. Plant tissue culture uses techniques to grow plant cells, tissues, or organs under sterile conditions on a nutrient culture medium. The type of media used depends on the plant species and material being cultured.
2. Common media include White's for root culture, MS for organogenesis and regeneration, B5 for cell suspension and callus culture, and N6 for cereal anther culture.
3. Media contains inorganic nutrients, carbon and energy sources, organic supplements like vitamins and amino acids, plant growth hormones, solidifying agents, and is sterilized before use.
The document describes the central dogma of molecular biology, which is the flow of genetic information from DNA to RNA to proteins. It covers DNA replication, transcription, translation, and how mutations can occur during these processes. DNA replication is semi-conservative and produces two identical DNA molecules from one original. Transcription produces mRNA from DNA, and translation uses mRNA to produce proteins according to the genetic code. Mutations can occur during replication, transcription or translation and result in changes to the amino acid sequence or reading frame of proteins.
Este documento describe la estructura y función de los ácidos nucleicos ADN y ARN. Los ácidos nucleicos son polímeros formados por la repetición de nucleótidos unidos mediante enlaces fosfodiéster. El ADN almacena y transmite la información genética de forma hereditaria a través de generaciones. El ARN tiene diversas funciones como dirigir la síntesis de proteínas y regular la expresión génica. Tanto el ADN como el ARN están formados por cadenas de nucleótidos compuestos por azúcares, bases
slide 2 central dogma
slide 3 key molecules used in translation
slide 4,5,6,7 all the key molcules with detail explanation
slide 8 phases of translation
slide 9 initiation and its process
slide 10 explanation initiation
slide 11 elongation and translocation
slide 12 process and steps of elongation and tRNA recharge in detail
slide 13 termination and its stages.
slide 14 diagrammatic representation of all the steps of termination with discrption
slide 15 thank you
This document provides an overview of DNA typing techniques used in forensics. It discusses the history of DNA analysis, beginning with its discovery and use in DNA fingerprinting in 1985. It also describes different DNA typing methods, including Restriction Fragment Length Polymorphism (RFLP), Polymerase Chain Reaction (PCR), and Short Tandem Repeats (STRs). Finally, it outlines the sample processing steps involving biology, technology, and genetics used to extract, amplify, separate, detect, and compare DNA from crime scene evidence and suspects.
1. DNA (deoxyribonucleic acid) is a chemical found in the nuclei of living cells that controls chemical changes and determines cell and organism type.
2. DNA is a long molecule composed of nucleotides, each containing a sugar (deoxyribose), phosphate group, and organic base (adenine, thymine, cytosine, or guanine).
3. DNA replicates before cell division by unwinding its double helix structure and using each strand as a template to make a new partner strand, resulting in two identical DNA molecules for each daughter cell after division.
Bioinformatics combines computer science, statistics, mathematics, and engineering to analyze biological data. Major bioinformatics databases and resources include NCBI, EMBL-EBI, and ExPASy. NCBI was established in 1988 as part of the National Library of Medicine and contains databases like PubMed, OMIM, and PubChem. EMBL-EBI was established in 1980 and provides DNA sequences and additional biological information through tools like Webin and SRS. ExPASy was established in 1993 by the Swiss Institute of Bioinformatics and contains protein databases like Swiss-Prot, TrEMBL, and InterPro.
The document summarizes the classic experiment conducted by Matthew Meselson and Frank Stahl in 1958 that determined the mechanism of DNA replication. They grew bacteria in a culture containing the heavy isotope nitrogen-15 to produce "heavy" DNA. When these bacteria were then grown in a culture with regular nitrogen-14, the resulting DNA had an intermediate density, indicating that DNA replicates semiconservatively, with each parent strand serving as a template to produce two daughter double helices. Subsequent experiments showed that after a second generation, the DNA was half heavy and half light, confirming the semiconservative model. This elegant experiment provided the first direct evidence that DNA replicates in this manner.
This document discusses RNA secondary structure prediction. It begins by defining RNA and its primary and secondary structures. The problem of predicting secondary structure given a primary sequence is introduced. Approaches include physical/chemical experiments and computational prediction using a single sequence. The Nussinov and Zuker algorithms are described. Nussinov finds the structure with maximum base pairs using dynamic programming. Zuker finds the minimum free energy structure also using dynamic programming. Addressing pseudoknots and other interactions is discussed as future work.
El documento describe tres tipos de ARN: ARNr, ARNt y ARNm. El ARNr es el más abundante y se encuentra en los ribosomas celulares. El ARNt transporta aminoácidos a los ribosomas durante la síntesis de proteínas. El ARNm transporta una copia del código genético del ADN a los ribosomas y especifica la secuencia de aminoácidos de las proteínas.
LocusLink is an online resource from the National Center for Biotechnology Information (NCBI) that provides a central point of access for basic biomedical information on genes, transcripts, and proteins from model organisms including human, rat, mouse, fruit fly, and zebrafish. It links to related NCBI databases such as PubMed, RefSeq, OMIM, GenBank, and others to provide curated gene sequence data, citations, and knowledge on genetic diseases. Users can search LocusLink by gene name or symbol and access descriptions and links to related data for the given genetic locus.
El documento describe los principales componentes y estructura de los ácidos nucleicos DNA y RNA. Explica que el DNA está formado por dos cadenas entrelazadas de nucleótidos unidos por enlaces fosfodiéster, mientras que el RNA normalmente es de una sola cadena. También resume el modelo de Watson-Crick para la estructura del DNA, el proceso de replicación semiconservativa del DNA, y los roles del DNA, RNA y proteínas en la expresión del código genético y síntesis de proteínas.
Introduction to Next-Generation Sequencing (NGS) TechnologyQIAGEN
The continuous evolution of NGS technology has led to an enormous diversification in NGS applications and dramatically decreased the costs to sequence a complete human genome.
In this presentation, we will discuss the following major topics:
• Basic overview of NGS sequencing technologies
• Next-generation sequencing workflow
• Spectrum of NGS applications
• QIAGEN universal NGS solutions
Sanger sequencing is a method of DNA sequencing based on the selective incorporation of chain-terminating dideoxynucleotides by DNA polymerase during in vitro DNA replication.
This document discusses RNA molecule structure prediction and the assumptions made, including that the most likely structure is similar to the most stable energetically, and that the energy of any position is only influenced by local sequence and structure. It also mentions complementary interactions of secondary structures and circle plots of base pairs.
RNA interference (RNAi) is a natural process in cells that uses small RNA molecules to regulate gene expression. Craig Fire and Andrew Mello discovered RNAi in 1998 through their experiments injecting double-stranded RNA into C. elegans worms. They found this silenced or interfered with the expression of genes with complementary RNA sequences. RNAi has important roles in defending against viruses and regulating development, with the small RNAs binding to messenger RNAs to decrease their activity. It has potential applications in gene therapy, functional genomics, agriculture, and more.
Introduction
Nucleic Acid Sequencing
Types of Nucleic Acid Sequencing
DNA Sequencing
Method of DNA Sequencing
Applications of DNA Sequencing
Conclusion
References
This document discusses the genetic material in living organisms. It covers:
1. The key properties of genetic material, including that it contains information passed from parents to offspring, replicates accurately, and is capable of change through evolution.
2. Experiments by Griffith, Avery, Hershey and Chase that identified DNA as the genetic material through labeling and tracking its transmission.
3. The history and structure of nucleic acids, including that they are made of nucleotides with a phosphate group, sugar (ribose in RNA, deoxyribose in DNA), and nitrogenous base. The two types are DNA and RNA.
4. DNA is a double-stranded molecule that exists in B-form and
This document discusses the collaboration between molecular medicine and bioinformatics. It defines bioinformatics as the science of storing, retrieving, and analyzing large amounts of biological data, cutting across biology, computer science, and mathematics. It gives examples of how bioinformatics can be applied in molecular medicine for studying pathogenicity, therapeutic targets, molecular diagnostics, and host-pathogen interactions. The document also outlines how bioinformatics supports molecular medicine through genome analysis, database and tool development, and describes some catalysts like genome sequencing that have expanded bioinformatics.
POST TRANSCRIPTIONAL MODIFICATIONS IN EUKARYOTESSidra Shaffique
1) Eukaryotic mRNAs undergo post-transcriptional processing in the cell nucleus, including addition of a 5' cap and 3' polyadenylated tail.
2) The 5' cap consists of a 7-methylguanosine residue joined to the initial nucleotide via a 5'-5' triphosphate bridge, and is added co-transcriptionally.
3) Mature mRNAs also contain a poly(A) tail of around 250 nucleotides added by poly(A) polymerase to the 3' end after cleavage of the primary transcript.
This document provides an overview of DNA including its structure, function, discovery, testing, and applications. It discusses that DNA contains the instructions for development, life, and reproduction and is found in every cell. The structure of DNA is a double helix formed from nucleotides. DNA can be tested to determine genetic disorders, carrier status, and disease risk. Mutations in DNA can cause changes in organisms. DNA has many uses including genetic engineering, fingerprinting, personalized healthcare, and industry applications. However, it also has risks if damaged or used for biological warfare.
In this slides the topic that which is discussed is "How PCR is involved in identification of Genotype"
I hope this will Help you in your presentation work.
"PCR can be used in identification of genotype."
The document discusses various aspects of genome organization, including:
1. Chromatin assembly begins with the incorporation of histone proteins to form nucleosomes, which are then folded and organized into higher order structures within the nucleus.
2. Genes can be split, overlapping, or pseudogenes. Split genes contain introns that are spliced out, while overlapping genes share nucleotide sequences. Pseudogenes are non-functional copies of genes.
3. Gene families consist of genes related by common ancestry that may be clustered or dispersed throughout the genome. Members can vary in sequence but often retain similar functions.
1. DNA (deoxyribonucleic acid) is a chemical found in the nuclei of living cells that controls chemical changes and determines cell and organism type.
2. DNA is a long molecule composed of nucleotides, each containing a sugar (deoxyribose), phosphate group, and organic base (adenine, thymine, cytosine, or guanine).
3. DNA replicates before cell division by unwinding its double helix structure and using each strand as a template to make a new partner strand, resulting in two identical DNA molecules for each daughter cell after division.
Bioinformatics combines computer science, statistics, mathematics, and engineering to analyze biological data. Major bioinformatics databases and resources include NCBI, EMBL-EBI, and ExPASy. NCBI was established in 1988 as part of the National Library of Medicine and contains databases like PubMed, OMIM, and PubChem. EMBL-EBI was established in 1980 and provides DNA sequences and additional biological information through tools like Webin and SRS. ExPASy was established in 1993 by the Swiss Institute of Bioinformatics and contains protein databases like Swiss-Prot, TrEMBL, and InterPro.
The document summarizes the classic experiment conducted by Matthew Meselson and Frank Stahl in 1958 that determined the mechanism of DNA replication. They grew bacteria in a culture containing the heavy isotope nitrogen-15 to produce "heavy" DNA. When these bacteria were then grown in a culture with regular nitrogen-14, the resulting DNA had an intermediate density, indicating that DNA replicates semiconservatively, with each parent strand serving as a template to produce two daughter double helices. Subsequent experiments showed that after a second generation, the DNA was half heavy and half light, confirming the semiconservative model. This elegant experiment provided the first direct evidence that DNA replicates in this manner.
This document discusses RNA secondary structure prediction. It begins by defining RNA and its primary and secondary structures. The problem of predicting secondary structure given a primary sequence is introduced. Approaches include physical/chemical experiments and computational prediction using a single sequence. The Nussinov and Zuker algorithms are described. Nussinov finds the structure with maximum base pairs using dynamic programming. Zuker finds the minimum free energy structure also using dynamic programming. Addressing pseudoknots and other interactions is discussed as future work.
El documento describe tres tipos de ARN: ARNr, ARNt y ARNm. El ARNr es el más abundante y se encuentra en los ribosomas celulares. El ARNt transporta aminoácidos a los ribosomas durante la síntesis de proteínas. El ARNm transporta una copia del código genético del ADN a los ribosomas y especifica la secuencia de aminoácidos de las proteínas.
LocusLink is an online resource from the National Center for Biotechnology Information (NCBI) that provides a central point of access for basic biomedical information on genes, transcripts, and proteins from model organisms including human, rat, mouse, fruit fly, and zebrafish. It links to related NCBI databases such as PubMed, RefSeq, OMIM, GenBank, and others to provide curated gene sequence data, citations, and knowledge on genetic diseases. Users can search LocusLink by gene name or symbol and access descriptions and links to related data for the given genetic locus.
El documento describe los principales componentes y estructura de los ácidos nucleicos DNA y RNA. Explica que el DNA está formado por dos cadenas entrelazadas de nucleótidos unidos por enlaces fosfodiéster, mientras que el RNA normalmente es de una sola cadena. También resume el modelo de Watson-Crick para la estructura del DNA, el proceso de replicación semiconservativa del DNA, y los roles del DNA, RNA y proteínas en la expresión del código genético y síntesis de proteínas.
Introduction to Next-Generation Sequencing (NGS) TechnologyQIAGEN
The continuous evolution of NGS technology has led to an enormous diversification in NGS applications and dramatically decreased the costs to sequence a complete human genome.
In this presentation, we will discuss the following major topics:
• Basic overview of NGS sequencing technologies
• Next-generation sequencing workflow
• Spectrum of NGS applications
• QIAGEN universal NGS solutions
Sanger sequencing is a method of DNA sequencing based on the selective incorporation of chain-terminating dideoxynucleotides by DNA polymerase during in vitro DNA replication.
This document discusses RNA molecule structure prediction and the assumptions made, including that the most likely structure is similar to the most stable energetically, and that the energy of any position is only influenced by local sequence and structure. It also mentions complementary interactions of secondary structures and circle plots of base pairs.
RNA interference (RNAi) is a natural process in cells that uses small RNA molecules to regulate gene expression. Craig Fire and Andrew Mello discovered RNAi in 1998 through their experiments injecting double-stranded RNA into C. elegans worms. They found this silenced or interfered with the expression of genes with complementary RNA sequences. RNAi has important roles in defending against viruses and regulating development, with the small RNAs binding to messenger RNAs to decrease their activity. It has potential applications in gene therapy, functional genomics, agriculture, and more.
Introduction
Nucleic Acid Sequencing
Types of Nucleic Acid Sequencing
DNA Sequencing
Method of DNA Sequencing
Applications of DNA Sequencing
Conclusion
References
This document discusses the genetic material in living organisms. It covers:
1. The key properties of genetic material, including that it contains information passed from parents to offspring, replicates accurately, and is capable of change through evolution.
2. Experiments by Griffith, Avery, Hershey and Chase that identified DNA as the genetic material through labeling and tracking its transmission.
3. The history and structure of nucleic acids, including that they are made of nucleotides with a phosphate group, sugar (ribose in RNA, deoxyribose in DNA), and nitrogenous base. The two types are DNA and RNA.
4. DNA is a double-stranded molecule that exists in B-form and
This document discusses the collaboration between molecular medicine and bioinformatics. It defines bioinformatics as the science of storing, retrieving, and analyzing large amounts of biological data, cutting across biology, computer science, and mathematics. It gives examples of how bioinformatics can be applied in molecular medicine for studying pathogenicity, therapeutic targets, molecular diagnostics, and host-pathogen interactions. The document also outlines how bioinformatics supports molecular medicine through genome analysis, database and tool development, and describes some catalysts like genome sequencing that have expanded bioinformatics.
POST TRANSCRIPTIONAL MODIFICATIONS IN EUKARYOTESSidra Shaffique
1) Eukaryotic mRNAs undergo post-transcriptional processing in the cell nucleus, including addition of a 5' cap and 3' polyadenylated tail.
2) The 5' cap consists of a 7-methylguanosine residue joined to the initial nucleotide via a 5'-5' triphosphate bridge, and is added co-transcriptionally.
3) Mature mRNAs also contain a poly(A) tail of around 250 nucleotides added by poly(A) polymerase to the 3' end after cleavage of the primary transcript.
This document provides an overview of DNA including its structure, function, discovery, testing, and applications. It discusses that DNA contains the instructions for development, life, and reproduction and is found in every cell. The structure of DNA is a double helix formed from nucleotides. DNA can be tested to determine genetic disorders, carrier status, and disease risk. Mutations in DNA can cause changes in organisms. DNA has many uses including genetic engineering, fingerprinting, personalized healthcare, and industry applications. However, it also has risks if damaged or used for biological warfare.
In this slides the topic that which is discussed is "How PCR is involved in identification of Genotype"
I hope this will Help you in your presentation work.
"PCR can be used in identification of genotype."
The document discusses various aspects of genome organization, including:
1. Chromatin assembly begins with the incorporation of histone proteins to form nucleosomes, which are then folded and organized into higher order structures within the nucleus.
2. Genes can be split, overlapping, or pseudogenes. Split genes contain introns that are spliced out, while overlapping genes share nucleotide sequences. Pseudogenes are non-functional copies of genes.
3. Gene families consist of genes related by common ancestry that may be clustered or dispersed throughout the genome. Members can vary in sequence but often retain similar functions.
4. Dezoksiriboza molekuluna
birləşmiş azot əsasları
nukleozidlər
adlanır.Nukleozidlər bir-birilə
fosfat turşusu qalığının köməyilə
qonşu nukleozidlərin karbon
atomu vasitəsilə
birləşirlər.Nukleozidin fosfat
turşusu qalığı ilə birləşməsi
monomer və nukleotid adlanan
DNT makromolekullarını təşkil
edir.
5. Nukleotidlərin nisbətinin şəkil dəyişməsində müəyyən
məhdudlaşmalar mövcuddur. Belə Ki, adeninin (A)
timinə (T) nisbəti, quaninin (Q) sitozinə (S) nisbəti
vahidə olduqca yaxındır, ancaq birinci (A+T) və ikinci
(Q+S) cüt əsasların cəmi miqdar nisbəti olduqca güclü
şəkildə dəyişə bilər. DNT makromolenulu bir–birinə
komplementar olan iki zəncirdən ibarətdir ki, burada
A, yaxud S-in bir zəncirdə olması müvafiq olaraq,
digərində T və Q-nin olmasına səbəb olur. Belə
bərabərliyi nəticəsində Q nisbi miqdarı və ona qoşa
olan S,həmçinin A miqdarda isə T miqdarın bərabərliyi
aydın izah oluna bilir.
6. DNT– nin iki zənciri azotlu birləşmələr arasında
yaranmış hidrogen rabitəsi ilə birləşmişdir. Spiral
burulduqda azot əsasları arasından H rabitəsi qırılır
və DNT-nin iki zənciri bir-birindən aralanır. Hər bir
zəncir üzərində DNT-nin struktur elementlərindən
yeni zəncir sintez olunur. Bu zaman hər bir əsasla
ona komplementar olan əsas elə əlaqələnir ki, hər
iki yeni zəncir valideyn zəncirə komplementar olur.
Beləliklə, bir ikiqat spiral əvəzinə onun iki dəqiq
surəti meydana çıxır. Bu proses DNT-nin
replikasiyası adını almışdır. DNT–nin belə dəqiq
replikasiyası adını almışdır.
7.
8. •DNT-polimeraza yeni DNT zəncirinin sintezidir.
Praymer matris zəncirinə komplementar olan
qısa nukleotid zənciri, RNT praymaza -RNT-nin
qısa nukleotid zənciridir. DNT-nin struktur
elementlərinin hər bir zəncirinə yeni zəncir sintez
olunur. Bu zaman ona komplementar olan əsas
qaynaqlaşdırılır, belə ki, 2 yeni zəncirdən hər biri
valideyn zəncirinə komplementar olacaqdır.
Beləliklə, 1 ikili spiralın əvəzinə onun 2 surəti
meydana çıxır. DNT-nin belə replikasiyası genetik
məlumatın saxlanmasına zəmanət verir
9. Genetik kod
Hər bir gen DNT molekulunun müəyyən sahəsi ilə
təmsil olunur. Gendə olan spesifik informasiya DNT
molekulu zəncirində əsasların ardıcıllığı ilə müəyyən
olunur. DNT informasiyası əlifbanın 4 hərfi vasitəsilə
işarə olunur: adenin (A), quanin (Q), timin (T) və
sitozin (S). mRNT–də timin urasillə (U) əvəz
olunmuşdur. Sintezinə genlər nəzarət edən zülal
fermentlərinin spesifikliyi polipeptid zəncirdə amin
turşularının ardıcıllığı ilə müəyyən olunur. Bu ardıcıllıq
zülalın məkan strukturunu, yəni informasiyanı (ikinci,
üçüncü və dördüncü struktur) təyin edir.
10. Nuklein turşusu dilindən amin turşusu dilinə keçilməsinə
spesifik kod xidmət edir. Hər bir amin turşusu üç qonşu
nukleotid qrupu ilə triplet və ya kodonla müəyyən olunur.
Nuklein turşularında tripletlərin bu və ya digər ardıcıllığı
birmənalıdır və polipeptid zəncirində amin turşularının
ardıcıllığını təyin edir. Tripletdə nukleotidlərin 64 müxtəlif
kombinasiyası ola bilər. Əgər hər bir 20 amin turşusu yalnız
bir tripletdə kodlaşarsa, onda 44 kombinasiya istifadə
olunmamış qalar. Ancaq məlum olmuşdur ki, bir çox amin
turşuları iki və daha çox müxtəlif tripletlə kodlaşır. Bəzi
tripletlər xüsusi məna kəsb edir,onlar polipeptid zəncirin
"başlanğıc" və "son"unu bildirir.
13. DNT irsi informasiyanın daşıyıcısı olsa da, polipeptidin sintezi
zamanı matriks rolunu daşımır. Zülalların biosintezi ribosomlarda
gedir və bunlar DNT ilə əlaqəli olmur. DNT–də qeyd olunmuş
informasiyanın zülal sintezi yerinə verilməsini matriks və ya
informasiya ribonuklein turşusu (m-RNT) həyata keçirir. RNT
polimer olub, DNT-dən dezoksiribozanın riboza ilə, timinin (T) isə
urasillə (U) əvəz edilməsi ilə fərqlənir. Quruluşuna görə birzəncirli
DNT–ni xatırladır. Matriks RNT DNT–nin hər hansı bir zəncirində
sintez olunur və bunun mexanizmi DNT-nin replikasiya
mexanizminə bənzəyir. Nukleotid əsasınm ardıcıllığına görə bunun
zənciri DNT zəncirinə komplementardır. Beləliklə, mRNT-nin
sintezində DNT-nin nukleotid ardıcıllığının surəti çıxarılır. Bu proses
transkripsiya adlanır və bu translyasiyamn əksi kimi qeyd olunur
14. Translyasiya
Amin turşuları mRNT tripletləri tərəfindən müəyyən olunmuş qaydada
polipeptid zənciri ilə birləşirlər. Bu prosesdə mRNT nəqliyyat RNT–si
(n-RNT), bir sıra fermentlər, ATF və digər faktorlar iştirak edir. Amin
turşularının aktivləşməsi və onun müvafiq n-RNT ilə birləşməsi spesifiıc
fermentaaminoasil RNTsintetaza ilə həyata keçirilir və bu da bir
tərəfdən amin turşusunu, digər tərəfdən isə müvafiq n-RNT-ni tanıyır.
20 müxtəlif sintetaza mövcuddur. Ribosomlar mRNT boyunca yerini
dəyişir və beləliklə, növbəti amin turşusunun yaranması və polipeptid
zəncirinin formalaşması baş verir. Eyni vaxtda polipeptid zəncirinin
burulması və kələf forması alması müşahidə edilir, bu isə öz növbəsində
amin turşularının ardıcıllığı və onların yan zəncirinin təbiəti ilə
müəyyən olunur.
15.
16. m-RNT-yə adətən, bir neçə ribosom birləşir və onun
həmin matriksdə eynı vaxtda bir neçə polipeptid
zənciri sintez olunur. Bir m-RNT-nin ribosomla belə
kompleksi polisom adlanır . Ribosomdan polipeptid
zəncirinin ayrılması prosesi m–RNT–nin ucunda
olan kodondan asılıdır. Beləliklə, DNT–nin nukleotid
ardıcıllığı spesifik zülalın strukturunu müəyyən
edən gen kodlaşmış “təlimatla” özunu göstərir.
Genetik materialı DNT olan bütün oqanizmlərdə
informasiya məhz bu yolla ötürülür.