5B86

Crystal structure of M-Sec

Summary for 5B86

• Entry DOI: 10.2210/pdb5b86/pdb
• Descriptor: Tumor necrosis factor alpha-induced protein 2 (2 entities in total)
• Functional Keywords: helical protein, exocyst complex, exocytosis, membrane traffic, immune system
• Biological source: Mus musculus (Mouse)
• Total number of polymer chains: 2
• Total formula weight: 137146.22

Authors

Yamashita, M.,Sato, Y.,Yamagata, A.,Fukai, S. (deposition date: 2016-06-12, release date: 2016-10-12, Last modification date: 2024-10-30)

Primary citation

Kimura, S.,Yamashita, M.,Yamakami-Kimura, M.,Sato, Y.,Yamagata, A.,Kobashigawa, Y.,Inagaki, F.,Amada, T.,Hase, K.,Iwanaga, T.,Ohno, H.,Fukai, S.
Distinct Roles for the N- and C-terminal Regions of M-Sec in Plasma Membrane Deformation during Tunneling Nanotube Formation.
Sci Rep, 6:33548-33548, 2016

PubMed Abstract: The tunneling nanotube (TNT) is a structure used for intercellular communication, and is a thin membrane protrusion mediating transport of various signaling molecules and cellular components. M-Sec has potent membrane deformation ability and induces TNT formation in cooperation with the Ral/exocyst complex. Here, we show that the N-terminal polybasic region of M-Sec directly binds phosphatidylinositol (4,5)-bisphosphate for its localization to the plasma membrane during the initial stage of TNT formation. We further report a crystal structure of M-Sec, which consists of helix bundles arranged in a straight rod-like shape, similar to the membrane tethering complex subunits. A positively charged surface in the C-terminal domains is required for M-Sec interaction with active RalA to extend the plasma membrane protrusions. Our results suggest that the membrane-associated M-Sec recruits active RalA, which directs the exocyst complex to form TNTs.

PubMed: 27629377
DOI: 10.1038/srep33548

Experimental method

X-RAY DIFFRACTION (3.017 Å)