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In situ cryo-electron tomography reveals filamentous actin within the microtubule lumen.

ABSTRACT: Microtubules and filamentous (F-) actin engage in complex interactions to drive many cellular processes from subcellular organization to cell division and migration. This is thought to be largely controlled by proteins that interface between the two structurally distinct cytoskeletal components. Here, we use cryo-electron tomography to demonstrate that the microtubule lumen can be occupied by extended segments of F-actin in small molecule-induced, microtubule-based, cellular projections. We uncover an unexpected versatility in cytoskeletal form that may prompt a significant development of our current models of cellular architecture and offer a new experimental approach for the in situ study of microtubule structure and contents.

SUBMITTER: Paul DM

PROVIDER: S-EPMC7480112 | biostudies-literature | 2020 Sep

REPOSITORIES: biostudies-literature

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In situ cryo-electron tomography reveals filamentous actin within the microtubule lumen.

Paul Danielle M DM Mantell Judith J Borucu Ufuk U Coombs Jennifer J Surridge Katherine J KJ Squire John M JM Verkade Paul P Dodding Mark P MP

The Journal of cell biology 20200901 9

Microtubules and filamentous (F-) actin engage in complex interactions to drive many cellular processes from subcellular organization to cell division and migration. This is thought to be largely controlled by proteins that interface between the two structurally distinct cytoskeletal components. Here, we use cryo-electron tomography to demonstrate that the microtubule lumen can be occupied by extended segments of F-actin in small molecule-induced, microtubule-based, cellular projections. We unco ...[more]

PMID: 32478855

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