Molecular characterization and expression analysis of four isotypes of immunoglobulin light chain genes in orange-spotted grouper, Epinephelus coioides.

To date, many immunoglobulin (Ig) genes have been identified in diverse teleost species, but the contributions of different types of light chain (IgL) to the immune response remain unclear. Screening of a stimulated kidney cDNA library from orange-spotted grouper (Osg, Epinephelus coioides) resulted in the identification of 26 full Ig light chain (OsgIgL) coding sequences. These 26 OsgIgLs encoded peptides from 235 to 248 amino acid residues and could be grouped into five variable (V(L)) and four constant (C(L)) isotypes.