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bioRxiv · 10.1101/2021.01.11.426289

ADF and cofilin-1 collaborate to promote cortical actin flow and the leader bleb-based migration of confined cells

Ullo, M. F.·Logue, J. S.
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Abstract

Melanoma cells have been shown to undergo fast amoeboid (leader bleb-based) migration, requiring a single large bleb for migration. In leader blebs, is a rapid flow of cortical actin that drives the cell forward. Using RNAi, we find that co-depleting cofilin-1 and ADF led to a large increase in cortical actin, suggesting that both proteins regulate cortical actin. Furthermore, severing factors can promote contractility through the regulation of actin architecture. However, RNAi of cofilin-1 but not ADF led to a significant decrease in cell stiffness. We found cofilin-1 to be enriched at leader bleb necks, whereas RNAi of cofilin-1 and ADF reduced bleb sizes and the frequency of motile cells. Strikingly, cells without cofilin-1 and ADF had blebs with abnormally long necks. Many of these blebs failed to retract and displayed slow actin turnover. Collectively, our data identifies cofilin-1 and ADF as actin remodeling factors required for fast amoeboid migration.

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Ullo, M. F., Logue, J. S.. 2021-01-12. ADF and cofilin-1 collaborate to promote cortical actin flow and the leader bleb-based migration of confined cells. https://doi.org/10.1101/2021.01.11.426289

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