High impact information on Stam2

• We previously reported that the STAM family members STAM1 and STAM2 are phosphorylated on tyrosine upon stimulation with cytokines through the gammac-Jak3 signaling pathway, which is essential for T-cell development [1].
• These STAM1(-/-) STAM2(-/-) mice showed a significant reduction in thymocytes and a profound reduction in peripheral mature T cells [1].
• A deubiquitinating enzyme UBPY interacts with the Src homology 3 domain of Hrs-binding protein via a novel binding motif PX(V/I)(D/N)RXXKP [2].
• Association of Hbp with a binding partner(s) via the SH3 domain seems to be essential for Hbp to exert its function [2].
• In this study, we searched for Hbp-binding proteins by a far Western screening and isolated a mouse cDNA clone encoding a deubiquitinating enzyme mUBPY as an Hbp SH3-binding protein. mUBPY has two Hbp-SH3 domain binding sites [2].

Biological context of Stam2

• Deletion mutants of Hbp lacking either the SH3 domain or the Hrs binding domain showed dominantly negative effects on the intracellular degradation of a growth factor and its receptor, but not on the internalization of growth factor/receptor complexes [3].
• The tissue distribution of different Stam2 mRNA variants was determined by reverse transcription-polymerase chain reaction, and the consequences of the alternative splicing at the protein level were analyzed by western blot with the polyclonal anti-STAM2 antibody [4].
• Involvement of hrs binding protein in IgE receptor-triggered exocytosis in RBL-2H3 mast cells [5].

Anatomical context of Stam2

• CONCLUSIONS: Hbp is thought to be closely associated with Hrs on early endosomes [3].
• Signal-transducing adaptor molecules STAM1 and STAM2 are required for T-cell development and survival [1].

Physical interactions of Stam2

• Hbp was co-immunoprecipitated with Hrs, and its intracellular localization was similar to that of Hrs [3].

Other interactions of Stam2

• Here we show that STAM1 and STAM2 are localized to the endosomal membrane [6].
• A hrs binding protein having a Src homology 3 domain is involved in intracellular degradation of growth factors and their receptors [3].

References