SNAP23/25 and VAMP2 mediate exocytic event of transferrin receptor-containing recycling vesicles

Biology Open

Kiyotaka Hatsuzawa¹  Senye Takahashi²  Shohei Nozaki²  Hye-Won Shin²  Yohei Katoh²  Minako Kobayashi²  Kazuhisa Nakayama²  Keiji Kubo²  Chikako Yagi² 

[1] Division of Molecular Biology, Tottori University School of Life Science, Yonago, Tottori 683-8503, Japan;Graduate School of Pharmaceutical Sciences, Kyoto University, Sakyo-ku, Kyoto 606-8501, Japan;

关键词: SNAP23;    SNAP25;    VAMP2;    Exocyst;    Recycling endosome;    Transferrin receptor;    Exocytosis;   

DOI  :  10.1242/bio.012146

来源: DOAJ

【 摘 要 】

We recently showed that Rab11 is involved not only in formation of recycling vesicles containing the transferrin (Tfn)–transferrin receptor (TfnR) complex at perinuclear recycling endosomes but also in tethering of recycling vesicles to the plasma membrane (PM) in concert with the exocyst tethering complex. We here aimed at identifying SNARE proteins responsible for fusion of Tfn–TfnR-containing recycling vesicles with the PM, downstream of the exocyst. We showed that exocyst subunits, Sec6 and Sec8, can interact with SNAP23 and SNAP25, both of which are PM-localizing Qbc-SNAREs, and that depletion of SNAP23 and/or SNAP25 in HeLa cells suppresses fusion of Tfn–TfnR-containing vesicles with the PM, leading to accumulation of the vesicles at the cell periphery. We also found that VAMP2, an R-SNARE, is colocalized with endocytosed Tfn on punctate endosomal structures, and that its depletion in HeLa cells suppresses recycling vesicle exocytosis. These observations indicate that fusion of recycling vesicles with the PM downstream of the exocyst is mediated by SNAP23/25 and VAMP2, and provide novel insight into non-neuronal roles of VAMP2 and SNAP25.

【 授权许可】

Unknown