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ER tubules mark sites of mitochondrial division.

ABSTRACT: Mitochondrial structure and distribution are regulated by division and fusion events. Mitochondrial division is regulated by Dnm1/Drp1, a dynamin-related protein that forms helices around mitochondria to mediate fission. Little is known about what determines sites of mitochondrial fission within the mitochondrial network. The endoplasmic reticulum (ER) and mitochondria exhibit tightly coupled dynamics and have extensive contacts. We tested whether ER plays a role in mitochondrial division. We found that mitochondrial division occurred at positions where ER tubules contacted mitochondria and mediated constriction before Drp1 recruitment. Thus, ER tubules may play an active role in defining the position of mitochondrial division sites.

SUBMITTER: Friedman JR

PROVIDER: S-EPMC3366560 | biostudies-literature | 2011 Oct

REPOSITORIES: biostudies-literature

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ER tubules mark sites of mitochondrial division.

Friedman Jonathan R JR Lackner Laura L LL West Matthew M DiBenedetto Jared R JR Nunnari Jodi J Voeltz Gia K GK

Science (New York, N.Y.) 20110901 6054

Mitochondrial structure and distribution are regulated by division and fusion events. Mitochondrial division is regulated by Dnm1/Drp1, a dynamin-related protein that forms helices around mitochondria to mediate fission. Little is known about what determines sites of mitochondrial fission within the mitochondrial network. The endoplasmic reticulum (ER) and mitochondria exhibit tightly coupled dynamics and have extensive contacts. We tested whether ER plays a role in mitochondrial division. We fo ...[more]

PMID: 21885730

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