Cargando…

Distinct Roles for the N- and C-terminal Regions of M-Sec in Plasma Membrane Deformation during Tunneling Nanotube Formation

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...

Descripción completa

Detalles Bibliográficos
Autores principales: Kimura, Shunsuke, Yamashita, Masami, Yamakami-Kimura, Megumi, Sato, Yusuke, Yamagata, Atsushi, Kobashigawa, Yoshihiro, Inagaki, Fuyuhiko, Amada, Takako, Hase, Koji, Iwanaga, Toshihiko, Ohno, Hiroshi, Fukai, Shuya
Formato: Online Artículo Texto
Lenguaje:English
Publicado: Nature Publishing Group 2016
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5024327/
https://www.ncbi.nlm.nih.gov/pubmed/27629377
http://dx.doi.org/10.1038/srep33548
Descripción
Sumario: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.