Immunoglobulin Superfamily, Member 3 (IGSF3)

Saupe et al. (1998) isolated a human cDNA encoding a novel immunoglobulin (Ig)-like membrane protein, named immunoglobulin superfamily member-3 (IGSF3). The deduced 1,215-amino acid protein contains an N-terminal signal sequence followed by a large extracellular domain composed of 8 Ig-like domains with 7 potential N-glycosylation sites; a potential hydrophobic transmembrane domain; and a C-terminal charged cytoplasmic tail. The Ig-like domains are of the V type, and a search of the sequence databases revealed that the IGSF3 protein is 32% identical to human V7, a leukocyte surface protein. The authors detected a major 8-kb mRNA and minor 6- and 4-kb mRNA species in a variety of human tissues by Northern blot analysis.