Evolutionary and structural influences on light chain constant (CL) region of human and mouse immunoglobulins.

A comparison of five constant region sequences of human and mouse k and lambda immunoglobulin chains has been undertaken in order to reveal sequence homologies and evolutionary relationships. Simultaneously, a comparison with the three-dimensional structure of one mouse k-chain (McPC 603) has suggested structural reasons why many of the residues are invariant or conserved along k versus lambda lines. There are a number of residues that have remained invariant despite exposed positions for reasons that do not apppear to be connected with the folding of the CL domain.