HLA-A2 and HLA-B7 antigens are phosphorylated in vitro by rous sarcoma virus kinase (pp60v-src) at a tyrosine residue encoded in a highly conserved exon of the intracellular domain

Proc Natl Acad Sci U S A. 1983 May;80(10):2894-8. doi: 10.1073/pnas.80.10.2894.


HLA-A2 and -B7 antigens are phosphorylated by Rous sarcoma kinase (pp60v-src) in vitro. The phosphate group is attached to the heavy chains as determined by NaDodSO4/polyacrylamide gel electrophoresis. The site of phosphorylation was localized to the COOH-terminal intracellular domain by its susceptibility to limited trypsin proteolysis. Furthermore, the 32P-labeled amino acid is a single tyrosine residue located in the COOH terminus of the heavy chain. The protein sequences of known class I human and murine intracellular domains contain a highly conserved sequence -K-G-G-X-Y- located NH2-terminally to the single tyrosine residue of this domain. The DNA sequences that encode class I antigen intracellular domains were compared by computer with a homology matrix program. Exon 6 which encodes the conserved tyrosine-containing protein sequence in both human and mouse is 75% homologous across species and 90-100% homologous within species. The significance of the high degree of conservation within exon 6 is discussed.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Amino Acid Sequence
  • Avian Sarcoma Viruses / enzymology*
  • Base Sequence
  • HLA Antigens / genetics
  • HLA Antigens / metabolism*
  • HLA-A2 Antigen
  • HLA-B7 Antigen
  • Humans
  • Oncogene Protein pp60(v-src)
  • Phosphorylation
  • Tyrosine / metabolism
  • Viral Proteins / metabolism*


  • HLA Antigens
  • HLA-A2 Antigen
  • HLA-B7 Antigen
  • Viral Proteins
  • Tyrosine
  • Oncogene Protein pp60(v-src)