Final answer:
In the maturation of B cells, DNA recombinase removes most V and J segments during DNA rearrangement; only one V and J segment get spliced together. During RNA processing, all surplus V and J segments are removed to create the mature mRNA, while the constant region remains unchanged, resulting in a diverse set of antibodies.
Step-by-step explanation:
Immunoglobulin Light Chain Gene Splicing
During the maturation of germ-line B cells, a process of genetic recombination rearranges the immunoglobulin light chain genes. An enzyme known as DNA recombinase is responsible for excising most of the variable (V) and joining (J) segments from the DNA. This is followed by the splicing of one V segment to one J segment. After transcription, RNA processing removes all but one set of these V and J segments. The constant (C) region, however, remains unaltered and is common across all antibodies. This sophisticated process of recombination and splicing at both the DNA and RNA levels is vital for the creation of a diverse repertoire of antibodies, allowing for the recognition and neutralization of an array of antigens by the immune system.
The regions that are removed during RNA splicing to generate the mature mRNA for immunoglobulin light chain genes are the superfluous V and J segments, leaving only one V and one J segment that form the variable region of the mature immunoglobulin light chain. This results in each B cell producing a unique antibody with a unique antigen-binding site, contributing to the body's ability to respond to a vast diversity of pathogens.
The constant domain, which is the same in all antibodies and does not participate in antigen binding, is not affected by this rearrangement and remains intact in the mature mRNA.