ISOLATION AND CHARACTERIZATION OF CDNA CLONES FOR CHICKEN MAJOR HISTOCOMPATIBILITY COMPLEX CLASS-II MOLECULES

The chicken major histocompatibility complex (MHC); the B complex, is being intensively analysed at the DNA level. To further probe the mole cular structure of chicken MHC class II genes, cDNA clones coding for chicken MHC class II (B-L) beta chain molecules were isolated from an inbred G-B2 Leghorn chicken spleen and liver. Twenty-nine cDNA clones were isolated from the spleen and eight cDNA clones were isolated from the liver. Based on restriction maps, most clones could be clustered into one family of genes. Four cDNA clones were sequenced (S7, S10 and S19 from the spleen and L1, which was identical to S19, from the live r). Complete amino acid sequences of B-Lbeta chain molecules were pred icted from the nucleotide sequences of the cDNA clones. Although both the nature and the location of the conserved residues were similar in chicken and mammalian sequences, some species-specific differences wer e found, suggesting that the structures of the B-L molecules of this h aplotype are similar, but not identical, to their mammalian counterpar ts.