Sec61β facilitates the maintenance of endoplasmic reticulum homeostasis by associating microtubules

Protein & Cell

Shaoyu Lin¹  Juanming Shi¹  Yimeng Zhu²  Gangming Zhang²  Hong Zhang²  Junjie Hu² 

[1] Department of Genetics and Cell Biology, College of Life Sciences, Nankai University;National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences;

关键词: ER stress;    Microtubule;    Sec61β;    Translocon;    Ribosome;   

DOI  :  10.1007/s13238-017-0492-5

来源: DOAJ

【 摘 要 】

Abstract Sec61β, a subunit of the Sec61 translocon complex, is not essential in yeast and commonly used as a marker of endoplasmic reticulum (ER). In higher eukaryotes, such as Drosophila, deletion of Sec61β causes lethality, but its physiological role is unclear. Here, we show that Sec61β interacts directly with microtubules. Overexpression of Sec61β containing small epitope tags, but not a RFP tag, induces dramatic bundling of the ER and microtubule. A basic region in the cytosolic domain of Sec61β is critical for microtubule association. Depletion of Sec61β induces ER stress in both mammalian cells and Caenorhabditis elegans, and subsequent restoration of ER homeostasis correlates with the microtubule binding ability of Sec61β. Loss of Sec61β causes increased mobility of translocon complexes and reduced level of membrane-bound ribosomes. These results suggest that Sec61β may stabilize protein translocation by linking translocon complex to microtubule and provide insight into the physiological function of ER-microtubule interaction.

【 授权许可】

Unknown