STAM/EAST/Hbp adapter proteins - integrators of signalling pathways

STAM/EAST/Hbp family of proteins consists of eight members well conserved f rom yeast to mammals. The basic domain architecture is comprised of an N-te rminal Vps27, Hrs and STAM homology domain, a ubiquitin-interacting motif a nd a central Src homology-3 domain. Vertebrate members also carry an immuno receptor tyrosine-based activation motif. STAM/EAST/Hbp proteins become tyr osine-phosphorylated by a variety of cytokines and growth factors. STAM 1 a nd STAM 2A are involved in cytokine-mediated signalling for DNA synthesis a nd e-myc induction. EAST and STAM 2A/Hbp play a role in receptor-mediated e ndo- and exocytosis and probably also in the regulation of actin cytoskelet on. Knockout experiments implicate a role for STAM 1 in neural cell surviva l. A picture is emerging of STAM/EAST/Hbp proteins acting as integrators of thus far mechanistically disparate cellular signalling events. (C) 2001 Fe deration of European Biochemical Societies. Published by Elsevier Science B .V. All rights reserved.