A cDNA clone encoding the mouse Qa-1a histocompatibility antigen and proposed structure of the putative peptide binding site.
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.
Connolly
D J
DJ
Transplantation Biology Section, Clinical Research Centre, Harrow, UK.
Cotterill
L A
LA
Hederer
R A
RA
Thorpe
C J
CJ
Travers
P J
PJ
McVey
J H
JH
Dyson
J
J
Robinson
P J
PJ
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D001665:Binding Sites; D018076:DNA, Complementary / Q000302:isolation & purification*; D006183:H-2 Antigens / Q000235:genetics*; D015395:Histocompatibility Antigens Class I / Q000032:analysis / Q000737:chemistry / Q000235:genetics*; D051379:Mice; D008810:Mice, Inbred C57BL; D008969:Molecular Sequence Data; D014176:Protein Biosynthesis; D011817:Rabbits
D018076:DNA, Complementary; D006183:H-2 Antigens; D015395:Histocompatibility Antigens Class I; C032907:Q surface antigens