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Cross-linkers at growing microtubule ends generate forces that drive actin transport.

ABSTRACT: SignificanceComplex cellular processes such as cell migration require coordinated remodeling of both the actin and the microtubule cytoskeleton. The two networks for instance exert forces on each other via active motor proteins. Here we show that, surprisingly, coupling via passive cross-linkers can also result in force generation. We specifically study the transport of actin filaments by growing microtubule ends. We show by cell-free reconstitution experiments, computer simulations, and theoretical modeling that this transport is driven by the affinity of the cross-linker for the chemically distinct microtubule tip region. Our work predicts that growing microtubules could potentially rapidly relocate newly nucleated actin filaments to the leading edge of the cell and thus boost migration.

SUBMITTER: Alkemade C

PROVIDER: S-EPMC8931237 | biostudies-literature | 2022 Mar

REPOSITORIES: biostudies-literature

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Cross-linkers at growing microtubule ends generate forces that drive actin transport.

Alkemade Celine C Wierenga Harmen H Volkov Vladimir A VA Preciado López Magdalena M Akhmanova Anna A Ten Wolde Pieter Rein PR Dogterom Marileen M Koenderink Gijsje H GH

Proceedings of the National Academy of Sciences of the United States of America 20220310 11

SignificanceComplex cellular processes such as cell migration require coordinated remodeling of both the actin and the microtubule cytoskeleton. The two networks for instance exert forces on each other via active motor proteins. Here we show that, surprisingly, coupling via passive cross-linkers can also result in force generation. We specifically study the transport of actin filaments by growing microtubule ends. We show by cell-free reconstitution experiments, computer simulations, and theoret ...[more]

PMID: 35271394

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