Question

The laboratory you are working in is studying the regulation of immunoglobulin synthesis. You know that in order to produce the complete immunoglobulin protein, changes must occur at the DNA level. The production of complete immunoglobulin proteins occurs because of?

Rearrangement of DNA in the germline
Rearrangement of DNA in the B cells
Splicing of RNA in B cells
Deletion of immunoglobulin genes which are not needed
Reorganization of large chromosome fragments in the germline

Answer 1

The production of complete immunoglobulin proteins occurs through the rearrangement of gene segments encoding antibody polypeptides at the DNA level.

Step-by-step explanation:

The production of complete immunoglobulin proteins occurs because of rearrangement of gene segments encoding antibody polypeptides at the level of DNA. This rearrangement process involves enzymes like DNA recombinase that randomly excise V and J segments from the light chain gene in mature B cells. Splicing at the mRNA level further modifies the gene rearrangement, resulting in each antibody having a unique variable region capable of binding a different antigen.