Structural component of specialized membrane microdomains known as tetraspanin-enriched microdomains (TERMs), which act as platforms for receptor clustering and signaling (PubMed:27180357, PubMed:36078095). Participates thereby in diverse biological functions such as cell signal transduction, migration and protein trafficking (PubMed:25761241). Promotes ADAM17-mediated TNF processing through recruitment of ADAM17 to tetraspanin-enriched micro-domains (TEMs) (PubMed:36078095). Forms a complex with RICTOR and integrin alpha3/ITGA3 to mediate mTORC2 activation and AKT1 phosphorylation leading to cell migration (PubMed:25761241). Reduces apoptosis and autophagy induced by high glucose levels through forming a complex with mTOR and RICTOR (PubMed:35904232). Contributes to the maintenance of intestinal epithelial barrier and plays a role in the regulation of intestine inflammation by switching interferon gamma receptor 1/IFNGR1 from clathrin-dependent to lipid raft-dependent endocytosis route to limit STAT1 activation magnitude and duration (PubMed:37204469). Acts as a modulator of the endothelin axis by associating with endothelin converting enzyme ECE1 and regulating its activity of conversion of the endothelin-1 precursor to endothelin (PubMed:37835445). {ECO:0000269|PubMed:25761241, ECO:0000269|PubMed:27180357, ECO:0000269|PubMed:35904232, ECO:0000269|PubMed:36078095, ECO:0000269|PubMed:37204469, ECO:0000269|PubMed:37835445}. This is the function of TSPAN8 (tetraspanin 8, Ensembl gene identifier ENSG00000127324).