This gene was identified by the rapid tyrosine-phosphorylation of its product in response to cytokine stimulation. The encoded protein contains an [[SH3 ___domain]] and the [[immunoreceptor tyrosine-based activation motif]] (ITAM). This protein associates with [[JAK3]] and [[JAK2]] kinases via its ITAM region, and is phosphorylated by the [[JAK kinaseskinase]]s upon [[cytokine]] stimulation, which suggests the function of this protein is as an adaptor molecule involved in the downstream signaling of [[cytokine receptors]]. HGS/HRS (hepatocyte growth factor-regulated tyrosine kinase substrate) has been found to bind and counteract the function of this protein.<ref name="entrez" /> STAM1 contains multiple [[amino acid]] sites that are [[phosphorylated]] and [[ubiquitinated]].<ref>{{Cite web|title=STAM1 (human)|url=https://www.phosphosite.org/proteinAction.action?id=6864&showAllSites=true|access-date=2020-10-31|website=www.phosphosite.org}}</ref>
