Journal
JOURNAL OF CELL BIOLOGY
Volume 151, Issue 2, Pages 289-295Publisher
ROCKEFELLER UNIV PRESS
DOI: 10.1083/jcb.151.2.289
Keywords
exchange factor; small GTPase; secretion; ER-to-Golgi; tethering factor
Categories
Ask authors/readers for more resources
TRAPP, a novel complex that resides on early Golgi, mediates the targeting of ER-to-Golgi vesicles to the Golgi apparatus. Previous studies have shown that YPT1, which encodes the small OTP-binding protein that regulates membrane traffic at this stage of the secretory pathway, interacts genetically with BET3 and BET5. Bet3p and Bet5p are 2 of the 10 identified subunits of TRAPP. Here we show that TRAPP preferentially binds to the nucleotide-free form of Ypt1p. Mutants with defects in several TRAPP subunits are temperature-sensitive in their ability to displace GDP from Ypt1p. Furthermore, the purified TRAPP complex accelerates nucleotide exchange on Ypt1p. Our findings imply that Ypt1p, which is present on ER-to-Golgi transport vesicles, is activated at the Golgi once it interacts with TRAPP.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available