CD81, Official Symbol CD81provided by HGNC Official Full Name CD81 moleculeprovided by HGNC Primary source HGNC:HGNC:1701 See related Ensembl:ENSG00000110651 MIM:186845; AllianceGenome:HGNC:1701 Gene type protein coding RefSeq status REVIEWED Organism Homo sapiens Lineage Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi; Mammalia; Eutheria; Euarchontoglires; Primates; Haplorrhini; Catarrhini; Hominidae; Homo Also known as S5.7; CVID6; TAPA1; TSPAN28 Summary The protein encoded by this gene is a member of the transmembrane 4 superfamily, also known as the tetraspanin family. Most of these members are cell-surface proteins that are characterized by the presence of four hydrophobic domains. The proteins mediate signal transduction events that play a role in the regulation of cell development, activation, growth and motility. This encoded protein is a cell surface glycoprotein that is known to complex with integrins. This protein appears to promote muscle cell fusion and support myotube maintenance. Also it may be involved in signal transduction. This gene is localized in the tumor-suppressor gene region and thus it is a candidate gene for malignancies. Two transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Jul 2014] Expression Ubiquitous expression in endometrium (RPKM 241.8), fat (RPKM 237.1) and 25 other tissues See more Orthologs mouse all