Organization and structure of the Qa genes of the major histocompatibility complex of the C3H mouse: implications for Qa function and class I evolution.
We have determined the structure and organization of the entire Qa family of class I genes from the major histocompatibility complex of the C3H mouse. Restriction maps of overlapping lambda and cosmid clones reveal that there are only five Qak genes: Q1k, Q2k, Q4k, Q10k and a Q5/9 hybrid, presumably generated by unequal homologous recombination. The resulting deletion of Q6-Q9 is consistent with the Qa-2null phenotype of this mouse strain. We have sequenced the Qak genes, and predict that each may encode a class I molecule with a structure comparable with that proposed for the transplantation antigens. Furthermore, these Qa products should be able to bind peptides and interact with appropriate T-cell receptors. Interestingly, in comparing Qak and H-2k sequences, we find limited evidence of interlocus gene conversion between Qa and H-2 loci, suggesting that the Qa genes are not likely to serve as a reservoir of genetic information for the generation of H-2 diversity within this haplotype.
Department of Genetics, University of California, Berkeley 94720.
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Watts
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Davis
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Gaut
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Wheeler
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Hill
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Goodenow
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D005075:Biological Evolution; D002874:Chromosome Mapping; D004247:DNA / Q000235:genetics; D005785:Gene Conversion; D005805:Genes, MHC Class I; D006183:H-2 Antigens / Q000235:genetics; D015395:Histocompatibility Antigens Class I / Q000235:genetics*; D051379:Mice; D008809:Mice, Inbred C3H / Q000235:genetics* / Q000276:immunology; D008969:Molecular Sequence Data; D012689:Sequence Homology, Nucleic Acid
D006183:H-2 Antigens; D015395:Histocompatibility Antigens Class I; C032907:Q surface antigens; D004247:DNA