TRAPP I implicated in the specificity of tethering in ER-to-Golgi transport.
TRAPP is a conserved protein complex required early in the secretory pathway. Here, we report two forms of TRAPP, TRAPP I and TRAPP II, that mediate different transport events. Using chemically pure TRAPP I and COPII vesicles, we have reconstituted vesicle targeting in vitro. The binding of COPII vesicles to TRAPP I is specific, blocked by GTPgammaS, and, surprisingly, does not require other tethering factors. Our findings imply that TRAPP I is the receptor on the Golgi for COPII vesicles. Once the vesicle binds to TRAPP I, the small GTP binding protein Ypt1p is activated and other tethering factors are recruited.
Department of Cell Biology, Yale University, New Haven, CT 06520, USA.
M
M
Sacher
J
J
Barrowman
W
W
Wang
J
J
Horecka
Y
Y
Zhang
M
M
Pypaert
S
S
Ferro-Novick
D022181:COP-Coated Vesicles / Q000378:metabolism; D002268:Carboxypeptidases / Q000378:metabolism; D002352:Carrier Proteins / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D043402:Cathepsin A; D002499:Centrifugation, Density Gradient; D004721:Endoplasmic Reticulum / Q000378:metabolism*; D006026:Glycoside Hydrolases / Q000378:metabolism; D006056:Golgi Apparatus / Q000378:metabolism*; D016244:Guanosine 5'-O-(3-Thiotriphosphate) / Q000494:pharmacology; D046911:Macromolecular Substances; D008565:Membrane Proteins / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D009154:Mutation; D011485:Protein Binding / Q000187:drug effects; D020033:Protein Isoforms / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism; D021122:Protein Subunits; D021381:Protein Transport; D012441:Saccharomyces cerevisiae / Q000166:cytology / Q000235:genetics / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins; D013379:Substrate Specificity; D013696:Temperature; D033921:Vesicular Transport Proteins; D043324:beta-Fructofuranosidase; D020691:rab GTP-Binding Proteins / Q000378:metabolism
D002352:Carrier Proteins; D046911:Macromolecular Substances; D008565:Membrane Proteins; D020033:Protein Isoforms; D021122:Protein Subunits; D029701:Saccharomyces cerevisiae Proteins; D033921:Vesicular Transport Proteins; C406327:transport protein particle, TRAPP; D016244:Guanosine 5'-O-(3-Thiotriphosphate); D006026:Glycoside Hydrolases; D043324:beta-Fructofuranosidase; D002268:Carboxypeptidases; D043402:Cathepsin A; C060755:YPT1 protein, S cerevisiae; D020691:rab GTP-Binding Proteins