ERG30, a VAP-33-related protein, functions in protein transport mediated by COPI vesicles.
Intracellular transport of newly synthesized and mature proteins via vesicles is controlled by a large group of proteins. Here we describe a ubiquitous rat protein-endoplasmic reticulum (ER) and Golgi 30-kD protein (ERG30)-which shares structural characteristics with VAP-33, a 33-kD protein from Aplysia californica which was shown to interact with the synaptic protein VAMP. The transmembrane topology of the 30-kD ERG30 corresponds to a type II integral membrane protein, whose cytoplasmic NH(2) terminus contains a predicted coiled-coil motif. We localized ERG30 to the ER and to pre-Golgi intermediates by biochemical and immunocytochemical methods. Consistent with a role in vesicular transport, anti-ERG30 antibodies specifically inhibit intra-Golgi transport in vitro, leading to significant accumulation of COPI-coated vesicles. It appears that ERG30 functions early in the secretory pathway, probably within the Golgi and between the Golgi and the ER.
Soussan
L
L
Department of Biological Regulation, The Weizmann Institute of Science, Rehovot, 76100 Israel.
Burakov
D
D
Daniels
M P
MP
Toister-Achituv
M
M
Porat
A
A
Yarden
Y
Y
Elazar
Z
Z
D000595:Amino Acid Sequence; D000818:Animals; D000906:Antibodies / Q000494:pharmacology; D001483:Base Sequence; D001692:Biological Transport / Q000187:drug effects; D002352:Carrier Proteins / Q000737:chemistry / Q000235:genetics* / Q000276:immunology / Q000378:metabolism*; D002460:Cell Line; D003001:Cloning, Molecular; D018699:Coated Vesicles / Q000187:drug effects / Q000378:metabolism*; D020756:Coatomer Protein; D018870:Endoplasmic Reticulum, Rough / Q000378:metabolism; D015870:Gene Expression; D006056:Golgi Apparatus / Q000187:drug effects / Q000378:metabolism; D008565:Membrane Proteins / Q000737:chemistry / Q000235:genetics* / Q000276:immunology / Q000378:metabolism* / Q000502:physiology*; D008969:Molecular Sequence Data; D011485:Protein Binding; D017433:Protein Structure, Secondary; D051381:Rats; D050600:SNARE Proteins; D017384:Sequence Deletion; D017386:Sequence Homology, Amino Acid; D033921:Vesicular Transport Proteins; D015003:Yeasts / Q000235:genetics
D000906:Antibodies; D002352:Carrier Proteins; D020756:Coatomer Protein; C120695:ERG30 protein, rat; D008565:Membrane Proteins; D050600:SNARE Proteins; C114051:VAPA protein, human; C491919:Vapa protein, rat; D033921:Vesicular Transport Proteins