STRUCTURAL STUDIES ON THE MURINE IA ALLOANTIGENS .6. EVIDENCE THAT BOTH SUBUNITS OF THE I-A ALLOANTIGEN ARE ENCODED BY THE I-A SUBREGION

Abstract

The .alpha. and .beta. subunits of murine I-A alloantigens from several H-2 haplotypes were examined by comparative tryptic peptide mapping by using double label (3H and 14C) techniques. Significant structural variation between alleles was detected in both subunits. Tryptic digests of the .alpha. polypeptides from s, b and d showed only 65% co-elution with k; .beta.-chains from s, b, d and r were about 50% similar to the k.beta. subunit. Peptide analysis of the AK subunits from intra-H-2 recombinant strains indicated that .alpha. and .beta. polypeptides are encoded within the I-A subregion.