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Drp1 Tubulates the ER in a GTPase-Independent Manner.

ABSTRACT: Mitochondria are highly dynamic organelles that continuously grow, divide, and fuse. The division of mitochondria is crucial for human health. During mitochondrial division, the mechano-guanosine triphosphatase (GTPase) dynamin-related protein (Drp1) severs mitochondria at endoplasmic reticulum (ER)-mitochondria contact sites, where peripheral ER tubules interact with mitochondria. Here, we report that Drp1 directly shapes peripheral ER tubules in human and mouse cells. This ER-shaping activity is independent of GTP hydrolysis and located in a highly conserved peptide of 18 amino acids (termed D-octadecapeptide), which is predicted to form an amphipathic α helix. Synthetic D-octadecapeptide tubulates liposomes in vitro and the ER in cells. ER tubules formed by Drp1 promote mitochondrial division by facilitating ER-mitochondria interactions. Thus, Drp1 functions as a two-in-one protein during mitochondrial division, with ER tubulation and mechano-GTPase activities.

SUBMITTER: Adachi Y

PROVIDER: S-EPMC7680448 | biostudies-literature | 2020 Nov

REPOSITORIES: biostudies-literature

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Drp1 Tubulates the ER in a GTPase-Independent Manner.

Adachi Yoshihiro Y Kato Takashi T Yamada Tatsuya T Murata Daisuke D Arai Kenta K Stahelin Robert V RV Chan David C DC Iijima Miho M Sesaki Hiromi H

Molecular cell 20201104 4

Mitochondria are highly dynamic organelles that continuously grow, divide, and fuse. The division of mitochondria is crucial for human health. During mitochondrial division, the mechano-guanosine triphosphatase (GTPase) dynamin-related protein (Drp1) severs mitochondria at endoplasmic reticulum (ER)-mitochondria contact sites, where peripheral ER tubules interact with mitochondria. Here, we report that Drp1 directly shapes peripheral ER tubules in human and mouse cells. This ER-shaping activity ...[more]

PMID: 33152269

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