TRAPP, a highly conserved novel complex on the cis-Golgi that mediates vesicle docking and fusion.
We previously identified BET3 by its genetic interactions with BET1, a gene whose SNARE-like product acts in endoplasmic reticulum (ER)-to-Golgi transport. To gain insight into the function of Bet3p, we added three c-myc tags to its C-terminus and immunopurified this protein from a clarified detergent extract. Here we report that Bet3p is a member of a large complex ( approximately 800 kDa) that we call TRAPP (transport protein particle). We propose that TRAPP plays a key role in the targeting and/or fusion of ER-to-Golgi transport vesicles with their acceptor compartment. The localization of Bet3p to the cis-Golgi complex, as well as biochemical studies showing that Bet3p functions on this compartment, support this hypothesis. TRAPP contains at least nine other constituents, five of which have been identified and shown to be highly conserved novel proteins.
Sacher
M
M
Howard Hughes Medical Institute and the Department of Cell Biology, Yale University School of Medicine, New Haven, CT 06510, USA.
Jiang
Y
Y
Barrowman
J
J
Scarpa
A
A
Burston
J
J
Zhang
L
L
Schieltz
D
D
Yates
J R
JR
Abeliovich
H
H
Ferro-Novick
S
S
D000595:Amino Acid Sequence; D017124:Conserved Sequence; D004721:Endoplasmic Reticulum / Q000502:physiology*; D000939:Epitopes; D005656:Fungal Proteins / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism*; D006056:Golgi Apparatus / Q000502:physiology*; D049452:Green Fluorescent Proteins; D007425:Intracellular Membranes / Q000502:physiology; D008164:Luminescent Proteins / Q000378:metabolism; D046911:Macromolecular Substances; D008561:Membrane Fusion; D008565:Membrane Proteins / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism*; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D010446:Peptide Fragments / Q000737:chemistry; D016271:Proto-Oncogene Proteins c-myc / Q000096:biosynthesis / Q000737:chemistry; D011993:Recombinant Fusion Proteins / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000254:growth & development / Q000502:physiology*; D029701:Saccharomyces cerevisiae Proteins; D033921:Vesicular Transport Proteins
C098389:BET3 protein, S cerevisiae; D000939:Epitopes; D005656:Fungal Proteins; D008164:Luminescent Proteins; D046911:Macromolecular Substances; D008565:Membrane Proteins; D010446:Peptide Fragments; D016271:Proto-Oncogene Proteins c-myc; D011993:Recombinant Fusion Proteins; D029701:Saccharomyces cerevisiae Proteins; D033921:Vesicular Transport Proteins; D049452:Green Fluorescent Proteins