Multiple roles of the vesicular-SNARE TI-VAMP in post-Golgi and endosomal trafficking

Abstract 

SNARE (Soluble N-ethylmaleimide-sensitive factor attachment protein receptor) proteins are the core machinery of membrane fusion. Vesicular SNAREs (v-SNAREs) interact with their target SNAREs (t-SNAREs) to form SNARE complexes which mediate membrane fusion. Here we review the basic properties and functions of the v-SNARE TI-VAMP/VAMP7 (Tetanus neurotoxin insensitive-vesicle associated membrane protein). TI-VAMP interacts with its t-SNARE partners, particularly plasmalemmal syntaxins, to mediate membrane fusion and with several regulatory proteins especially via its amino-terminal regulatory Longin domain. Partners include AP-3, Hrb/(Human immunodeficiency virus Rev binding) protein, and Varp (Vps9 domain and ankyrin repeats containing protein) and regulate TI-VAMP’s function and targeting. TI-VAMP is involved both in secretory and endocytic pathways which mediate neurite outgrowth and synaptic transmission, plasma membrane remodeling and lysosomal secretion.

Abbreviations: SNARE, soluble N-ethylmaleimide-sensitive factor attachment protein receptor, t-SNARE, target SNARE, v-SNARE, vesicular-SNARE, TI-VAMP, Tetanus neurotoxin insensitive-vesicle associated membrane protein, SNAP, synaptosome associated protein, VAMP, vesicle associated membrane protein, Hrb, human immunodeficiency virus Rev binding protein, Varp, Vps9 domain and ankyrin repeats containing protein, TGN, trans-Golgi Network, ER, endoplasmic reticulum, SV, synaptic vesicle

Keywords: SNARE attachment protein receptor, TI-VAMP associated membrane protein, Post-Golgi, Traffic, Endosomal pathway, Secretion