A cDNA clone encoding the mouse Qa-1a histocompatibility antigen and proposed structure of the putative peptide binding site

J Immunol. 1993 Dec 1;151(11):6089-98.


We have isolated a cDNA clone which encodes the Qa-1a histocompatibility Ag from a library prepared from Con A-activated B10.BR mouse spleen cells. The clone encodes a protein of 322 amino acids with three potential N-glycosylation sites. The coding sequence shows strongest similarity with that of the T23d gene of DBA/2 mice which encodes the Qa-1b molecule. Molecular modeling of the putative peptide-combining site indicates most of the differences between Qa-1a and Qa-1b are located peripheral to the binding cleft, with only two amino acid substitutions, at positions 9 and 24, which might affect peptide binding. Many features of the Qa-1 binding cleft are also conserved in the rat RTBM.1 and in human HLA-E molecules. This suggests that all of these molecules may associate with structurally similar peptides.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Base Sequence
  • Binding Sites
  • DNA, Complementary / isolation & purification*
  • H-2 Antigens / genetics*
  • Histocompatibility Antigens Class I / analysis
  • Histocompatibility Antigens Class I / chemistry
  • Histocompatibility Antigens Class I / genetics*
  • Mice
  • Mice, Inbred C57BL
  • Molecular Sequence Data
  • Protein Biosynthesis
  • Rabbits


  • DNA, Complementary
  • H-2 Antigens
  • Histocompatibility Antigens Class I
  • Q surface antigens

Associated data

  • GENBANK/L00606