Complementry dna Library CDNA library

1. Complementary DNA LIBRARY
(C DNA Library)
A.VELKUMAR
II M.Sc MICROBIOLOGY
BIOTECHNOLOGY
SUBMITTED TO,
DR.G.RAMANATHAN
ASSISTANT PROFESSOR
SPKC-ALWARKURICHI
BIOTECHNOLOGY

2. CDNA LIBRARY
CDNA – Complementary DNA
It is a combination of cloned DNA
fragments inserted in a collection of
host cells which are arranged in a Petri
dish

3. CDNA LIBRARY
1 synthesise of cDNA
2 Construction of cDNA Library

4. 1 . Synthesis of cDNA
STEPS :
(i) Extraction of mRNA from the eukaryotic cells
(ii) Construction of cDNA from the Extracted mRNA

5. (i) . Extraction of mRNA from cells

7. (ii) . Construction of cDNA from mRNA

8. (ii) . Construction of cDNA from mRNA

9. 2 . Construction of cDNA Library

11. ELECTROPORATION
Pore to cell membrane
using electric current
(100-150 volts)

12. Applications of cDNA Library:
Following are the applications of cDNA libraries:
1. Discovery of novel genes.
2. Cloning of full-length cDNA molecules for in vitro study of gene
function.
3. Study of the repertoire of mRNAs expressed in different cells or
tissues.
4. Study of alternative splicing in different cells or tissues.

13. ADVANTAGES
▪It is enriched with fragments from actively transcribed genes.
▪Introns do not interrupt the cloned sequences; introns would
pose a problem when the goal is to produce a eukaryotic
protein in bacteria.

14. DISADVANTAGES
• It contains only sequences that are present in mature mRNA.
• Introns and any other sequences that are not present after
transcription.
• Sequences, such as promoters and enhancers, that are not
transcribed into RNA also are not present in a cDNA library.

15. REFERENCES
NOTES
• https://www.biotechnologynotes.com/dna-libraries/notes-on-cdna-
library-dna-libraries/517
• https://www.onlinebiologynotes.com/cdna-library-process-of-
construction-of-cdna-library-advantages-and-disadvantages/
VIDEOS
• https://youtu.be/sZCnYJ9K3A4
• https://youtu.be/ufI0-DzdOUQ