SlideShare a Scribd company logo
1 of 21
cDNA ANDGENOMIC
LIBRARIES
MRS. S.AMIRTHAM
ASSITANT PROFESSOR
PG & RESEARCH DEPARTMENT OF BIOTECHNOLOGY
BON SECOURS COLLEGE FOR WOMEN
THANJAVUR
INTRODUCTION
 A DNA library is a collection of DNA clones ,gathered together as
a source of DNA for sequencing, gene discovery , or gene function
studies .
 There are two types of DNAlibraries:
1.DNA
2. Genomic
cDNA LIBRARY
 AcDNAlibrary is a set of cDNAclones prepared from the mRNAs
isolates from a particular type of tissue.
 The cDNA library contains only complementry DNAmolecules
synthesized from mRNA molecules in a cell.
 This molecules represents all the gene that are expressed in the cell
at different stage of its development.
No cDNAwas made from
prokaryotic mRNA
 Prokaryotic mRNA is very unstable.
 Genomic libraries of prokaryotes are easier to make and contain
all the genome sequences.
cDNA Libraries Are VeryUseful
For Eukaryotic Gene Analysis
 Condensed protein encoded gene libraries,Have much less
junk sequences
 cDNAs have no introns→genes can be expressed in E. coli
directly
 Are very useful to identify new genes
 Tissue or cell type specific(differential expression of genes)
Synthesis of Cdna:
 FIRST STAND SYNTHESIS: materials as reverse
transcriptase, primer(oligo(dT) or hexanucleotides) and
dNTPs
 SECOUND STRAND SYNTHESIS: best way of making full-
length cDNA is to ‘tail’ the 3’- end of the first strand and then
use a complementary primer to make the secound.
CONSTRUCTION
cDNA libraries are constructed by synthesizing cDNA
from purified cellular mRNA via oligo(dT)-cellulose
chromatography.
This is done to recover the poly(A) mRNA so as to
anneal with the oligo(dT) chains .
SCREENING
 A prope is a piece of DNA or RNA used to detect specific nucleic
acid sequence by hybridization ( binding of two nucleic acid chains
by base pairing). Oligonucleotide can be used as a probe.
 They are radioactivity labeled so that the hybridized nucleicacid
can be identified by autoratiography.
Two general approaches are avilable for screening libraries to
identify clones carrying a gene or other DNA region ofinterest.
Detection with oligonucleotide probes that bind to the clone of
interest .
Detection based on expression of the encoded protein.
A PLASMID cDNA LIBRARY
FOR SCREENING
GENOMIC LIBRARY
 Is the largest type of library which consist of the complete
genome of a complete genome of a particular organism
which is cleaved into thousands of fragments, are all the
fragments are cloned by insertion into a cloning vector.
 A collection of clones that collectively represent all the DNA
sequences in the genome of a particular organism.
CONSTRUCTION
 The first step in preparing a genomic library is partial
digestion of the DNA by restriction endonucleases, such that
any given sequences will appear in fragments of a range of
sizes and is represented in the library.
 Secondly,the cloning vector ,such as a BAC or YAC plasmid
,is cleaved with the same restriction endonuclease and
ligated to the genomic DNAfragment.
 Thereafter ligated DNA mixture is then used to transform bacterial oryeast
cells to produce a library of cell types,each type harboring a different
recombinant DNAmolecule.
 Each transformed bacterium or yeast cell grows into a colony,or “clone”,of
identical cells,each cell bearing the same recombinant plasmid.
 The ability to clone such large DNA fragments raise the possibility ofthe
Genomic library,but it has been found that there is a problem as to what
number of clones are required to construct a genomiclibrary.
 A solution has been provided with thw use of afornuker:
N=ln(1-P)/ln(1-a/b)
 Which enchances the capacity of constructing a genomic library,and also
ease the problem of screening.(i.e..the higher the fragments,the smaller the
number of clones).
SCREENING
 A common method of screening is the plasmid- based genomic
libraries which is to carry out a colony hybridization experiment.
Host bacteria containing either a plasmid based or bacteriophage-
based library are plated out on petri dish and allowed to grow
overnight to form colonies.
CONCLUSION
 In conclusion, genomic DNA segments can be organized in librariesknown
as genomic libraries and cDNA libraries with a wide range of designs and
purposes.
THANK YOU

More Related Content

What's hot

Genomic and c dna library
Genomic and c dna libraryGenomic and c dna library
Genomic and c dna libraryPromila Sheoran
 
CDNA Library preparation. ppt for Jamil sir
CDNA Library preparation. ppt for Jamil sirCDNA Library preparation. ppt for Jamil sir
CDNA Library preparation. ppt for Jamil sirNushrat Jahan
 
transfection and invitro packaging of phage genome
transfection and invitro packaging of phage genometransfection and invitro packaging of phage genome
transfection and invitro packaging of phage genomeNOMI KhanS
 
Restriction mapping
Restriction mappingRestriction mapping
Restriction mappingMinali Singh
 
cDNA Library Construction
cDNA Library ConstructioncDNA Library Construction
cDNA Library ConstructionStella Evelyn
 
Shuttle vector - a plasmid vector used in rDNA technology.
Shuttle vector - a plasmid vector used in rDNA technology. Shuttle vector - a plasmid vector used in rDNA technology.
Shuttle vector - a plasmid vector used in rDNA technology. neeru02
 
cohesive and blunt end ligation
cohesive and blunt end ligationcohesive and blunt end ligation
cohesive and blunt end ligationleo prabha
 
bacterial artificial chromosome & yeast artificial chromosome
bacterial artificial chromosome & yeast artificial chromosomebacterial artificial chromosome & yeast artificial chromosome
bacterial artificial chromosome & yeast artificial chromosomeashapatel676
 
lambda cloning vector
lambda cloning vectorlambda cloning vector
lambda cloning vectorNOMI KhanS
 
Lectut btn-202-ppt-l4. bacteriophage lambda and m13 vectors (1)
Lectut btn-202-ppt-l4. bacteriophage lambda and m13 vectors (1)Lectut btn-202-ppt-l4. bacteriophage lambda and m13 vectors (1)
Lectut btn-202-ppt-l4. bacteriophage lambda and m13 vectors (1)Rishabh Jain
 

What's hot (20)

Genomic and c dna library
Genomic and c dna libraryGenomic and c dna library
Genomic and c dna library
 
CDNA Library preparation. ppt for Jamil sir
CDNA Library preparation. ppt for Jamil sirCDNA Library preparation. ppt for Jamil sir
CDNA Library preparation. ppt for Jamil sir
 
transfection and invitro packaging of phage genome
transfection and invitro packaging of phage genometransfection and invitro packaging of phage genome
transfection and invitro packaging of phage genome
 
Pyrosequencing
PyrosequencingPyrosequencing
Pyrosequencing
 
Restriction mapping
Restriction mappingRestriction mapping
Restriction mapping
 
cDNA Library Construction
cDNA Library ConstructioncDNA Library Construction
cDNA Library Construction
 
Shuttle vector - a plasmid vector used in rDNA technology.
Shuttle vector - a plasmid vector used in rDNA technology. Shuttle vector - a plasmid vector used in rDNA technology.
Shuttle vector - a plasmid vector used in rDNA technology.
 
cohesive and blunt end ligation
cohesive and blunt end ligationcohesive and blunt end ligation
cohesive and blunt end ligation
 
bacterial artificial chromosome & yeast artificial chromosome
bacterial artificial chromosome & yeast artificial chromosomebacterial artificial chromosome & yeast artificial chromosome
bacterial artificial chromosome & yeast artificial chromosome
 
cDNA Library
cDNA LibrarycDNA Library
cDNA Library
 
Artificial chromosomes - YAC and BAC
Artificial chromosomes - YAC and BACArtificial chromosomes - YAC and BAC
Artificial chromosomes - YAC and BAC
 
M13 phage
M13 phageM13 phage
M13 phage
 
Cloning strategies
Cloning strategiesCloning strategies
Cloning strategies
 
lambda cloning vector
lambda cloning vectorlambda cloning vector
lambda cloning vector
 
Lambda vector
Lambda vectorLambda vector
Lambda vector
 
P bluescript
P bluescriptP bluescript
P bluescript
 
Exprssion vector
Exprssion vectorExprssion vector
Exprssion vector
 
Lamda phage
Lamda phageLamda phage
Lamda phage
 
Lectut btn-202-ppt-l4. bacteriophage lambda and m13 vectors (1)
Lectut btn-202-ppt-l4. bacteriophage lambda and m13 vectors (1)Lectut btn-202-ppt-l4. bacteriophage lambda and m13 vectors (1)
Lectut btn-202-ppt-l4. bacteriophage lambda and m13 vectors (1)
 
Sv 40
Sv 40Sv 40
Sv 40
 

Similar to C dna and genomic libraries amirtham

C dna and genomic libraries copy
C dna and genomic libraries   copyC dna and genomic libraries   copy
C dna and genomic libraries copychristanantony
 
Construction of genomic and c dna library
Construction of genomic and c dna libraryConstruction of genomic and c dna library
Construction of genomic and c dna libraryNaveenJ46
 
Genomic and c dna library by Kailash Sontakke
Genomic and c dna library by Kailash SontakkeGenomic and c dna library by Kailash Sontakke
Genomic and c dna library by Kailash SontakkeKAILASHSONTAKKE
 
Principle and procedure for making Genomic library and cDNA library.pptx
Principle and procedure for making Genomic library and cDNA library.pptxPrinciple and procedure for making Genomic library and cDNA library.pptx
Principle and procedure for making Genomic library and cDNA library.pptxPrabhatSingh628463
 
Dna library lecture-Gene libraries and screening
Dna library lecture-Gene libraries and screening  Dna library lecture-Gene libraries and screening
Dna library lecture-Gene libraries and screening Abdullah Abobakr
 
genomic library.pptx
genomic library.pptxgenomic library.pptx
genomic library.pptxHussainTaqi1
 
Dna library CONSTRUCTION
Dna library CONSTRUCTIONDna library CONSTRUCTION
Dna library CONSTRUCTIONMSCW Mysore
 
Molecular Cloning.pptx
Molecular Cloning.pptxMolecular Cloning.pptx
Molecular Cloning.pptxlalvarezmex
 
genetic_engineering__unit_3__lecture_1.ppt
genetic_engineering__unit_3__lecture_1.pptgenetic_engineering__unit_3__lecture_1.ppt
genetic_engineering__unit_3__lecture_1.pptUmehabiba502674
 
DNA Libraries PPT
DNA Libraries PPTDNA Libraries PPT
DNA Libraries PPTSayooj M R
 

Similar to C dna and genomic libraries amirtham (20)

C dna and genomic libraries copy
C dna and genomic libraries   copyC dna and genomic libraries   copy
C dna and genomic libraries copy
 
C dna
C dnaC dna
C dna
 
Gene library
Gene libraryGene library
Gene library
 
DNA library ppt.pptx
DNA library ppt.pptxDNA library ppt.pptx
DNA library ppt.pptx
 
Construction of genomic and c dna library
Construction of genomic and c dna libraryConstruction of genomic and c dna library
Construction of genomic and c dna library
 
Genomic and c dna library by Kailash Sontakke
Genomic and c dna library by Kailash SontakkeGenomic and c dna library by Kailash Sontakke
Genomic and c dna library by Kailash Sontakke
 
3 dna libraries
3 dna libraries3 dna libraries
3 dna libraries
 
Principle and procedure for making Genomic library and cDNA library.pptx
Principle and procedure for making Genomic library and cDNA library.pptxPrinciple and procedure for making Genomic library and cDNA library.pptx
Principle and procedure for making Genomic library and cDNA library.pptx
 
Dna library lecture-Gene libraries and screening
Dna library lecture-Gene libraries and screening  Dna library lecture-Gene libraries and screening
Dna library lecture-Gene libraries and screening
 
genomic library.pptx
genomic library.pptxgenomic library.pptx
genomic library.pptx
 
genomic library
genomic librarygenomic library
genomic library
 
Dna library CONSTRUCTION
Dna library CONSTRUCTIONDna library CONSTRUCTION
Dna library CONSTRUCTION
 
Genomic library
Genomic libraryGenomic library
Genomic library
 
Molecular Cloning.pptx
Molecular Cloning.pptxMolecular Cloning.pptx
Molecular Cloning.pptx
 
Genomic library
Genomic libraryGenomic library
Genomic library
 
Application1
Application1Application1
Application1
 
genetic_engineering__unit_3__lecture_1.ppt
genetic_engineering__unit_3__lecture_1.pptgenetic_engineering__unit_3__lecture_1.ppt
genetic_engineering__unit_3__lecture_1.ppt
 
DNA Libraries PPT
DNA Libraries PPTDNA Libraries PPT
DNA Libraries PPT
 
cDNA library construction
cDNA library constructioncDNA library construction
cDNA library construction
 
cDNA Library Construction
cDNA Library ConstructioncDNA Library Construction
cDNA Library Construction
 

More from christanantony

More from christanantony (20)

Pcr molecular diagnosis
Pcr molecular diagnosisPcr molecular diagnosis
Pcr molecular diagnosis
 
Pcr and its application
Pcr and its applicationPcr and its application
Pcr and its application
 
Gene silencing amirtham
Gene silencing   amirthamGene silencing   amirtham
Gene silencing amirtham
 
Cloning pcr amirtham
Cloning pcr   amirthamCloning pcr   amirtham
Cloning pcr amirtham
 
Spectroscopy amirtham
Spectroscopy   amirthamSpectroscopy   amirtham
Spectroscopy amirtham
 
Electrophoresis amirtham
Electrophoresis   amirthamElectrophoresis   amirtham
Electrophoresis amirtham
 
Crystallography amirtham
Crystallography   amirthamCrystallography   amirtham
Crystallography amirtham
 
Chromatography amirtham
Chromatography   amirthamChromatography   amirtham
Chromatography amirtham
 
Centrifugation amirtham
Centrifugation   amirthamCentrifugation   amirtham
Centrifugation amirtham
 
Calorimeter
CalorimeterCalorimeter
Calorimeter
 
Daisy gene 123
Daisy gene  123Daisy gene  123
Daisy gene 123
 
Presentation
Presentation Presentation
Presentation
 
Cloning pcr
Cloning pcrCloning pcr
Cloning pcr
 
Labelling of dna
Labelling of dnaLabelling of dna
Labelling of dna
 
Spectroscopy
SpectroscopySpectroscopy
Spectroscopy
 
Electrophoresis wps office
Electrophoresis wps officeElectrophoresis wps office
Electrophoresis wps office
 
Crystallography
CrystallographyCrystallography
Crystallography
 
Centrifugation
Centrifugation Centrifugation
Centrifugation
 
Centrifugation by akasthiya
Centrifugation  by akasthiyaCentrifugation  by akasthiya
Centrifugation by akasthiya
 
Types of pcr ppt by mala (1)
Types of pcr ppt by mala (1)Types of pcr ppt by mala (1)
Types of pcr ppt by mala (1)
 

Recently uploaded

A Giant Impact Origin for the First Subduction on Earth
A Giant Impact Origin for the First Subduction on EarthA Giant Impact Origin for the First Subduction on Earth
A Giant Impact Origin for the First Subduction on EarthSérgio Sacani
 
Pests of Green Manures_Bionomics_IPM_Dr.UPR.pdf
Pests of Green Manures_Bionomics_IPM_Dr.UPR.pdfPests of Green Manures_Bionomics_IPM_Dr.UPR.pdf
Pests of Green Manures_Bionomics_IPM_Dr.UPR.pdfPirithiRaju
 
Microbial bio Synthesis of nanoparticles.pptx
Microbial bio Synthesis of nanoparticles.pptxMicrobial bio Synthesis of nanoparticles.pptx
Microbial bio Synthesis of nanoparticles.pptxCherry
 
Quantifying Artificial Intelligence and What Comes Next!
Quantifying Artificial Intelligence and What Comes Next!Quantifying Artificial Intelligence and What Comes Next!
Quantifying Artificial Intelligence and What Comes Next!University of Hertfordshire
 
INSIGHT Partner Profile: Tampere University
INSIGHT Partner Profile: Tampere UniversityINSIGHT Partner Profile: Tampere University
INSIGHT Partner Profile: Tampere UniversitySteffi Friedrichs
 
Exomoons & Exorings with the Habitable Worlds Observatory I: On the Detection...
Exomoons & Exorings with the Habitable Worlds Observatory I: On the Detection...Exomoons & Exorings with the Habitable Worlds Observatory I: On the Detection...
Exomoons & Exorings with the Habitable Worlds Observatory I: On the Detection...Sérgio Sacani
 
mixotrophy in cyanobacteria: a dual nutritional strategy
mixotrophy in cyanobacteria: a dual nutritional strategymixotrophy in cyanobacteria: a dual nutritional strategy
mixotrophy in cyanobacteria: a dual nutritional strategyMansiBishnoi1
 
The Scientific names of some important families of Industrial plants .pdf
The Scientific names of some important families of Industrial plants .pdfThe Scientific names of some important families of Industrial plants .pdf
The Scientific names of some important families of Industrial plants .pdfMohamed Said
 
GBSN - Microbiology (Unit 7) Microbiology in Everyday Life
GBSN - Microbiology (Unit 7) Microbiology in Everyday LifeGBSN - Microbiology (Unit 7) Microbiology in Everyday Life
GBSN - Microbiology (Unit 7) Microbiology in Everyday LifeAreesha Ahmad
 
Aerodynamics. flippatterncn5tm5ttnj6nmnynyppt
Aerodynamics. flippatterncn5tm5ttnj6nmnynypptAerodynamics. flippatterncn5tm5ttnj6nmnynyppt
Aerodynamics. flippatterncn5tm5ttnj6nmnynypptsreddyrahul
 
Mitosis...............................pptx
Mitosis...............................pptxMitosis...............................pptx
Mitosis...............................pptxCherry
 
family therapy psychotherapy types .pdf
family therapy psychotherapy types  .pdffamily therapy psychotherapy types  .pdf
family therapy psychotherapy types .pdfhaseebahmeddrama
 
Isolation of AMF by wet sieving and decantation method pptx
Isolation of AMF by wet sieving and decantation method pptxIsolation of AMF by wet sieving and decantation method pptx
Isolation of AMF by wet sieving and decantation method pptxGOWTHAMIM22
 
The solar dynamo begins near the surface
The solar dynamo begins near the surfaceThe solar dynamo begins near the surface
The solar dynamo begins near the surfaceSérgio Sacani
 
ERTHROPOIESIS: Dr. E. Muralinath & R. Gnana Lahari
ERTHROPOIESIS: Dr. E. Muralinath & R. Gnana LahariERTHROPOIESIS: Dr. E. Muralinath & R. Gnana Lahari
ERTHROPOIESIS: Dr. E. Muralinath & R. Gnana Laharimuralinath2
 
Emergent ribozyme behaviors in oxychlorine brines indicate a unique niche for...
Emergent ribozyme behaviors in oxychlorine brines indicate a unique niche for...Emergent ribozyme behaviors in oxychlorine brines indicate a unique niche for...
Emergent ribozyme behaviors in oxychlorine brines indicate a unique niche for...Sérgio Sacani
 
Ostiguy & Panizza & Moffitt (eds.) - Populism in Global Perspective. A Perfor...
Ostiguy & Panizza & Moffitt (eds.) - Populism in Global Perspective. A Perfor...Ostiguy & Panizza & Moffitt (eds.) - Populism in Global Perspective. A Perfor...
Ostiguy & Panizza & Moffitt (eds.) - Populism in Global Perspective. A Perfor...frank0071
 
MODERN PHYSICS_REPORTING_QUANTA_.....pdf
MODERN PHYSICS_REPORTING_QUANTA_.....pdfMODERN PHYSICS_REPORTING_QUANTA_.....pdf
MODERN PHYSICS_REPORTING_QUANTA_.....pdfRevenJadePalma
 
Cell Immobilization Methods and Applications.pptx
Cell Immobilization Methods and Applications.pptxCell Immobilization Methods and Applications.pptx
Cell Immobilization Methods and Applications.pptxCherry
 
Climate extremes likely to drive land mammal extinction during next supercont...
Climate extremes likely to drive land mammal extinction during next supercont...Climate extremes likely to drive land mammal extinction during next supercont...
Climate extremes likely to drive land mammal extinction during next supercont...Sérgio Sacani
 

Recently uploaded (20)

A Giant Impact Origin for the First Subduction on Earth
A Giant Impact Origin for the First Subduction on EarthA Giant Impact Origin for the First Subduction on Earth
A Giant Impact Origin for the First Subduction on Earth
 
Pests of Green Manures_Bionomics_IPM_Dr.UPR.pdf
Pests of Green Manures_Bionomics_IPM_Dr.UPR.pdfPests of Green Manures_Bionomics_IPM_Dr.UPR.pdf
Pests of Green Manures_Bionomics_IPM_Dr.UPR.pdf
 
Microbial bio Synthesis of nanoparticles.pptx
Microbial bio Synthesis of nanoparticles.pptxMicrobial bio Synthesis of nanoparticles.pptx
Microbial bio Synthesis of nanoparticles.pptx
 
Quantifying Artificial Intelligence and What Comes Next!
Quantifying Artificial Intelligence and What Comes Next!Quantifying Artificial Intelligence and What Comes Next!
Quantifying Artificial Intelligence and What Comes Next!
 
INSIGHT Partner Profile: Tampere University
INSIGHT Partner Profile: Tampere UniversityINSIGHT Partner Profile: Tampere University
INSIGHT Partner Profile: Tampere University
 
Exomoons & Exorings with the Habitable Worlds Observatory I: On the Detection...
Exomoons & Exorings with the Habitable Worlds Observatory I: On the Detection...Exomoons & Exorings with the Habitable Worlds Observatory I: On the Detection...
Exomoons & Exorings with the Habitable Worlds Observatory I: On the Detection...
 
mixotrophy in cyanobacteria: a dual nutritional strategy
mixotrophy in cyanobacteria: a dual nutritional strategymixotrophy in cyanobacteria: a dual nutritional strategy
mixotrophy in cyanobacteria: a dual nutritional strategy
 
The Scientific names of some important families of Industrial plants .pdf
The Scientific names of some important families of Industrial plants .pdfThe Scientific names of some important families of Industrial plants .pdf
The Scientific names of some important families of Industrial plants .pdf
 
GBSN - Microbiology (Unit 7) Microbiology in Everyday Life
GBSN - Microbiology (Unit 7) Microbiology in Everyday LifeGBSN - Microbiology (Unit 7) Microbiology in Everyday Life
GBSN - Microbiology (Unit 7) Microbiology in Everyday Life
 
Aerodynamics. flippatterncn5tm5ttnj6nmnynyppt
Aerodynamics. flippatterncn5tm5ttnj6nmnynypptAerodynamics. flippatterncn5tm5ttnj6nmnynyppt
Aerodynamics. flippatterncn5tm5ttnj6nmnynyppt
 
Mitosis...............................pptx
Mitosis...............................pptxMitosis...............................pptx
Mitosis...............................pptx
 
family therapy psychotherapy types .pdf
family therapy psychotherapy types  .pdffamily therapy psychotherapy types  .pdf
family therapy psychotherapy types .pdf
 
Isolation of AMF by wet sieving and decantation method pptx
Isolation of AMF by wet sieving and decantation method pptxIsolation of AMF by wet sieving and decantation method pptx
Isolation of AMF by wet sieving and decantation method pptx
 
The solar dynamo begins near the surface
The solar dynamo begins near the surfaceThe solar dynamo begins near the surface
The solar dynamo begins near the surface
 
ERTHROPOIESIS: Dr. E. Muralinath & R. Gnana Lahari
ERTHROPOIESIS: Dr. E. Muralinath & R. Gnana LahariERTHROPOIESIS: Dr. E. Muralinath & R. Gnana Lahari
ERTHROPOIESIS: Dr. E. Muralinath & R. Gnana Lahari
 
Emergent ribozyme behaviors in oxychlorine brines indicate a unique niche for...
Emergent ribozyme behaviors in oxychlorine brines indicate a unique niche for...Emergent ribozyme behaviors in oxychlorine brines indicate a unique niche for...
Emergent ribozyme behaviors in oxychlorine brines indicate a unique niche for...
 
Ostiguy & Panizza & Moffitt (eds.) - Populism in Global Perspective. A Perfor...
Ostiguy & Panizza & Moffitt (eds.) - Populism in Global Perspective. A Perfor...Ostiguy & Panizza & Moffitt (eds.) - Populism in Global Perspective. A Perfor...
Ostiguy & Panizza & Moffitt (eds.) - Populism in Global Perspective. A Perfor...
 
MODERN PHYSICS_REPORTING_QUANTA_.....pdf
MODERN PHYSICS_REPORTING_QUANTA_.....pdfMODERN PHYSICS_REPORTING_QUANTA_.....pdf
MODERN PHYSICS_REPORTING_QUANTA_.....pdf
 
Cell Immobilization Methods and Applications.pptx
Cell Immobilization Methods and Applications.pptxCell Immobilization Methods and Applications.pptx
Cell Immobilization Methods and Applications.pptx
 
Climate extremes likely to drive land mammal extinction during next supercont...
Climate extremes likely to drive land mammal extinction during next supercont...Climate extremes likely to drive land mammal extinction during next supercont...
Climate extremes likely to drive land mammal extinction during next supercont...
 

C dna and genomic libraries amirtham

  • 1. cDNA ANDGENOMIC LIBRARIES MRS. S.AMIRTHAM ASSITANT PROFESSOR PG & RESEARCH DEPARTMENT OF BIOTECHNOLOGY BON SECOURS COLLEGE FOR WOMEN THANJAVUR
  • 2. INTRODUCTION  A DNA library is a collection of DNA clones ,gathered together as a source of DNA for sequencing, gene discovery , or gene function studies .  There are two types of DNAlibraries: 1.DNA 2. Genomic
  • 3. cDNA LIBRARY  AcDNAlibrary is a set of cDNAclones prepared from the mRNAs isolates from a particular type of tissue.  The cDNA library contains only complementry DNAmolecules synthesized from mRNA molecules in a cell.  This molecules represents all the gene that are expressed in the cell at different stage of its development.
  • 4. No cDNAwas made from prokaryotic mRNA  Prokaryotic mRNA is very unstable.  Genomic libraries of prokaryotes are easier to make and contain all the genome sequences.
  • 5. cDNA Libraries Are VeryUseful For Eukaryotic Gene Analysis  Condensed protein encoded gene libraries,Have much less junk sequences  cDNAs have no introns→genes can be expressed in E. coli directly  Are very useful to identify new genes  Tissue or cell type specific(differential expression of genes)
  • 6. Synthesis of Cdna:  FIRST STAND SYNTHESIS: materials as reverse transcriptase, primer(oligo(dT) or hexanucleotides) and dNTPs  SECOUND STRAND SYNTHESIS: best way of making full- length cDNA is to ‘tail’ the 3’- end of the first strand and then use a complementary primer to make the secound.
  • 7. CONSTRUCTION cDNA libraries are constructed by synthesizing cDNA from purified cellular mRNA via oligo(dT)-cellulose chromatography. This is done to recover the poly(A) mRNA so as to anneal with the oligo(dT) chains .
  • 8. SCREENING  A prope is a piece of DNA or RNA used to detect specific nucleic acid sequence by hybridization ( binding of two nucleic acid chains by base pairing). Oligonucleotide can be used as a probe.  They are radioactivity labeled so that the hybridized nucleicacid can be identified by autoratiography.
  • 9. Two general approaches are avilable for screening libraries to identify clones carrying a gene or other DNA region ofinterest. Detection with oligonucleotide probes that bind to the clone of interest . Detection based on expression of the encoded protein.
  • 10. A PLASMID cDNA LIBRARY FOR SCREENING
  • 11.
  • 12.
  • 13. GENOMIC LIBRARY  Is the largest type of library which consist of the complete genome of a complete genome of a particular organism which is cleaved into thousands of fragments, are all the fragments are cloned by insertion into a cloning vector.  A collection of clones that collectively represent all the DNA sequences in the genome of a particular organism.
  • 14. CONSTRUCTION  The first step in preparing a genomic library is partial digestion of the DNA by restriction endonucleases, such that any given sequences will appear in fragments of a range of sizes and is represented in the library.  Secondly,the cloning vector ,such as a BAC or YAC plasmid ,is cleaved with the same restriction endonuclease and ligated to the genomic DNAfragment.
  • 15.  Thereafter ligated DNA mixture is then used to transform bacterial oryeast cells to produce a library of cell types,each type harboring a different recombinant DNAmolecule.  Each transformed bacterium or yeast cell grows into a colony,or “clone”,of identical cells,each cell bearing the same recombinant plasmid.  The ability to clone such large DNA fragments raise the possibility ofthe Genomic library,but it has been found that there is a problem as to what number of clones are required to construct a genomiclibrary.
  • 16.  A solution has been provided with thw use of afornuker: N=ln(1-P)/ln(1-a/b)  Which enchances the capacity of constructing a genomic library,and also ease the problem of screening.(i.e..the higher the fragments,the smaller the number of clones).
  • 17.
  • 18. SCREENING  A common method of screening is the plasmid- based genomic libraries which is to carry out a colony hybridization experiment. Host bacteria containing either a plasmid based or bacteriophage- based library are plated out on petri dish and allowed to grow overnight to form colonies.
  • 19.
  • 20. CONCLUSION  In conclusion, genomic DNA segments can be organized in librariesknown as genomic libraries and cDNA libraries with a wide range of designs and purposes.