SH3 DOMAIN-DEPENDENT INTERACTIONS OF ENDOPHILIN WITH AMPHIPHYSIN

Amphiphysin I and II are nerve terminal-enriched proteins thought to f unction in synaptic vesicle endocytosis. In addition to a C-terminal S H3 domain, the proteins contain a highly conserved putative SH3 bindin g site and numerous consensus phosphorylation sites, We now demonstrat e that amphiphysin a but not amphiphysin HP is a phosphoprotein which undergoes dephosphorylation during nerve terminal depolarization, Furt her, both amphiphysin I and PI interact with the SH3 domain of endophi lin, a synaptically enriched protein implicated in synaptic vesicle en docytosis. The interaction is direct sind mediated through a 43 amino acid region of amphiphysin containing the putative SH3 binding site. T hese data further support a role for amphiphysin I, II and endophilin in synaptic vesicle endocytosis. (C) 1997 Federation of European Bioch emical Societies.