Characterization of two class I major histocompatibility rat cDNA clones, one of which contains a premature termination codon.
A cDNA clone that shares considerable homology with mRNA for class-I major-histocompatibility (MHC) antigens has been isolated from a cDNA library constructed from an insulin-secreting tumor of the NEDH rat (RIN). Although there is very strong homology between the third extracellular domain of this gene, and other class-I antigen genes, a stop codon was noticed at the junction between the external and transmembrane regions of its protein. Thus, this gene codes for a truncated class-I antigen that lacks both transmembrane and cytoplasmic domains but has hydrophilic amino acids towards its C-terminus and therefore resembles a soluble protein. This gene was found to be transcribed at significant levels in the rat testis and an insulin-secreting tumor, but transcription was negligible in liver and kidney. The partial nucleotide sequence of this gene in a Wistar rat genomic clone indicates that the cDNA clone is represented in the rat genome complete with premature termination codon, thus eliminating the possibility of artifactual origins for the clone.
D000818:Animals; D001483:Base Sequence; D003062:Codon; D004247:DNA / Q000235:genetics; D005786:Gene Expression Regulation; D005796:Genes; D006649:Histocompatibility Antigens / Q000235:genetics*; D008285:Major Histocompatibility Complex; D010443:Peptide Chain Termination, Translational; D051381:Rats / Q000235:genetics / Q000276:immunology*
D003062:Codon; D006649:Histocompatibility Antigens; D004247:DNA