5HAS

Crystal structure of the N-terminal DCB-HUS domain of T. terrestris Sec7

Summary for 5HAS

• Entry DOI: 10.2210/pdb5has/pdb
• Descriptor: Sec7 (2 entities in total)
• Functional Keywords: armadillo, arf-gef, tgn, transport, protein transport
• Biological source: Thielavia terrestris
• Total number of polymer chains: 4
• Total formula weight: 207572.28

Authors

Richardson, B.C.,Fromme, J.C. (deposition date: 2015-12-30, release date: 2016-01-27, Last modification date: 2024-03-06)

Primary citation

Richardson, B.C.,Halaby, S.L.,Gustafson, M.A.,Fromme, J.C.
The Sec7 N-terminal regulatory domains facilitate membrane-proximal activation of the Arf1 GTPase.
Elife, 5:-, 2016

PubMed Abstract: The Golgi complex is the central sorting compartment of eukaryotic cells. Arf guanine nucleotide exchange factors (Arf-GEFs) regulate virtually all traffic through the Golgi by activating Arf GTPase trafficking pathways. The Golgi Arf-GEFs contain multiple autoregulatory domains, but the precise mechanisms underlying their function remain largely undefined. We report a crystal structure revealing that the N-terminal DCB and HUS regulatory domains of the Arf-GEF Sec7 form a single structural unit. We demonstrate that the established role of the N-terminal region in dimerization is not conserved; instead, a C-terminal autoinhibitory domain is responsible for dimerization of Sec7. We find that the DCB/HUS domain amplifies the ability of Sec7 to activate Arf1 on the membrane surface by facilitating membrane insertion of the Arf1 amphipathic helix. This enhancing function of the Sec7 N-terminal domains is consistent with the high rate of Arf1-dependent trafficking to the plasma membrane necessary for maximal cell growth.

PubMed: 26765562
DOI: 10.7554/eLife.12411

Experimental method

X-RAY DIFFRACTION (2.653 Å)