Expression cloning of a cDNA encoding a novel murine B cell activation marker. Homology to human CD38.

摘要: A rat mAb (NIM-R5) has recently been prepared against a novel murine B cell activation marker. We report here isolation of cDNA (1-19) encoding the cell-derived protein recognized by NIM-R5 antibody. This contains an open reading frame that encodes polypeptide 304 amino acids with predicted molecular weight 34,500. The existence 22-amino acid hydrophobic region located 23 from terminal deduced protein, together four potential N-linked glycosylation sites, characterize encoded I-19 as typical type II transmembrane glycoprotein. Although appears to encode its nucleotide sequence and show approximately 70% homology previously reported human CD38, suggesting either mouse homologue CD38 or closely related protein. Northern blot analysis expression this product in variety types, immunoprecipitation recombinant expressed BaF3 cells, indicated not only epitope but also is indistinguishable biochemically terms distribution marker Chromosomal mapping studies have localized locus proximal chromosome 5. anticipate availability probes for NIM-R5, itself, will greatly aid efforts define role molecule development.