5CA8

Structures of the yeast dynamin-like GTPase Sey1p in complex with GDP

Summary for 5CA8

• Entry DOI: 10.2210/pdb5ca8/pdb
• Related: 5CA9 5CB2
• Descriptor: Protein SEY1, MAGNESIUM ION, GUANOSINE-5'-DIPHOSPHATE, ... (4 entities in total)
• Functional Keywords: er, homo-fusion, dynamin, hydrolase
• Biological source: Candida albicans (strain SC5314 / ATCC MYA-2876) (Yeast)
• Total number of polymer chains: 1
• Total formula weight: 79591.51

Authors

Yan, L. (deposition date: 2015-06-29, release date: 2015-09-16, Last modification date: 2024-11-06)

Primary citation

Yan, L.,Sun, S.,Wang, W.,Shi, J.,Hu, X.,Wang, S.,Su, D.,Rao, Z.,Hu, J.,Lou, Z.
Structures of the yeast dynamin-like GTPase Sey1p provide insight into homotypic ER fusion
J.Cell Biol., 210:961-972, 2015

PubMed Abstract: Homotypic membrane fusion of the endoplasmic reticulum is mediated by dynamin-like guanosine triphosphatases (GTPases), which include atlastin (ATL) in metazoans and Sey1p in yeast. In this paper, we determined the crystal structures of the cytosolic domain of Sey1p derived from Candida albicans. The structures reveal a stalk-like, helical bundle domain following the GTPase, which represents a previously unidentified configuration of the dynamin superfamily. This domain is significantly longer than that of ATL and critical for fusion. Sey1p forms a side-by-side dimer in complex with GMP-PNP or GDP/AlF4(-) but is monomeric with GDP. Surprisingly, Sey1p could mediate fusion without GTP hydrolysis, even though fusion was much more efficient with GTP. Sey1p was able to replace ATL in mammalian cells, and the punctate localization of Sey1p was dependent on its GTPase activity. Despite the common function of fusogenic GTPases, our results reveal unique features of Sey1p.

PubMed: 26370501
DOI: 10.1083/jcb.201502078

Experimental method

X-RAY DIFFRACTION (2.3 Å)