Question

List the steps to build a gene library?

Answer 1

A gene library contains a clone of each and every gene that is present in the cells of any organism. This happens due to the fact that the starting material in a genomic library is that DNA which is extracted from an organism out of interest.

Complete answer-
A genomic library consists of fragments of DNA in either form of bacteriophage or P1 derived artificial chromosome. Each of these phages contain a DNA molecule that has a fragmentary insert of cellular DNA obtained from a foreign organism.
Following are the steps to build a gene library:
1. The required DNA should be extracted from the organism and then purified.
2. Using the restriction enzyme the DNA should be made into gene-size pieces.
3. With the help of the same restriction enzyme cut a cloning plasmid.
4. Add all the plasmid and genomic DNA and DNA ligase to a test tube. This will lead to the formation of a collection of recombinant and non-recombinant plasmids.
5. Transfer this collection of plasmids into the strain of E.coli in the laboratory so that it becomes susceptible to antibodies.
6. Now put this bacteria on the X-gel plate and incubate it at body temperature overnight.
7. Observe this plate and select the white colonies so that they can be transferred to the new X-gel plate.
8. Now it’s time to make a large collection of white colonies to form the genomic library.

Note-
One very important use of this gene library is that once it is made it can be used to extract the colonies that contain any gene of the organism. The difficult part arises in identifying as to which gene of the organism they are interested in and from which organism it should be extracted.