STAM Gene: Function, Expression, and Role in Disease

STAM (Signal Transducing Adaptor Molecule) encodes a member of the STAM family of adaptor proteins. It contains an SH3 domain and an ITAM (immunoreceptor tyrosine-based activation motif) region. STAM is involved in cytokine-mediated signal transduction, particularly in the JAK-STAT pathway, and plays a critical role in endosomal sorting of ubiquitinated cargo via the ESCRT-0 complex. It is essential for receptor downregulation and lysosomal degradation.

Tissue Expression

Cell Line Expression

Hotspot Mutations

Mutation functional classification

• ESCRT-0 complex (endosomal sorting)

• JAK-STAT signaling pathway

• EGFR downregulation and degradation

• Interleukin-2 signaling

STAM is a 540-amino-acid adaptor protein (UniProt Q92783) that contains an N-terminal VHS domain, a central coiled-coil region, an SH3 domain, and a C-terminal ITAM-like motif. It forms a complex with HRS (HGS) to constitute the ESCRT-0 complex, which recognizes ubiquitinated membrane proteins and sorts them into multivesicular bodies for lysosomal degradation. STAM also participates in signal transduction downstream of cytokine receptors, including IL-2 and GM-CSF, by recruiting STAT proteins.