3CUE
Crystal structure of a TRAPP subassembly activating the Rab Ypt1p
Summary for 3CUE
| Entry DOI | 10.2210/pdb3cue/pdb |
| Descriptor | Transport protein particle 23 kDa subunit, Transport protein particle 31 kDa subunit, Transport protein particle 18 kDa subunit, ... (6 entities in total) |
| Functional Keywords | membrane traffic, gef, tethering complex, rab activation, guanine nucleotide exchange factor, endoplasmic reticulum, er-golgi transport, golgi apparatus, transport, lipoprotein, palmitate, gtp-binding, nucleotide-binding, phosphoprotein, prenylation, protein transport |
| Biological source | Saccharomyces cerevisiae (Baker's yeast) More |
| Cellular location | Golgi apparatus, cis-Golgi network: Q03784 Q03337 Q03630 P36149 Endoplasmic reticulum membrane; Peripheral membrane protein: P01123 |
| Total number of polymer chains | 24 |
| Total formula weight | 571601.47 |
| Authors | Cai, Y.,Reinisch, K.M. (deposition date: 2008-04-16, release date: 2008-07-08, Last modification date: 2024-10-16) |
| Primary citation | Cai, Y.,Chin, H.F.,Lazarova, D.,Menon, S.,Fu, C.,Cai, H.,Sclafani, A.,Rodgers, D.W.,De La Cruz, E.M.,Ferro-Novick, S.,Reinisch, K.M. The structural basis for activation of the Rab Ypt1p by the TRAPP membrane-tethering complexes. Cell(Cambridge,Mass.), 133:1202-1213, 2008 Cited by PubMed Abstract: The multimeric membrane-tethering complexes TRAPPI and TRAPPII share seven subunits, of which four (Bet3p, Bet5p, Trs23p, and Trs31p) are minimally needed to activate the Rab GTPase Ypt1p in an event preceding membrane fusion. Here, we present the structure of a heteropentameric TRAPPI assembly complexed with Ypt1p. We propose that TRAPPI facilitates nucleotide exchange primarily by stabilizing the nucleotide-binding pocket of Ypt1p in an open, solvent-accessible form. Bet3p, Bet5p, and Trs23p interact directly with Ypt1p to stabilize this form, while the C terminus of Bet3p invades the pocket to participate in its remodeling. The Trs31p subunit does not interact directly with the GTPase but allosterically regulates the TRAPPI interface with Ypt1p. Our findings imply that TRAPPII activates Ypt1p by an identical mechanism. This view of a multimeric membrane-tethering assembly complexed with a Rab provides a framework for understanding events preceding membrane fusion at the molecular level. PubMed: 18585354DOI: 10.1016/j.cell.2008.04.049 PDB entries with the same primary citation |
| Experimental method | X-RAY DIFFRACTION (3.7 Å) |
Structure validation
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