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PubMed · 15633455

Regulating filopodial dynamics through actin-depolymerizing factor/cofilin.

Joseph Fass·Scott Gehler·Patrick Sarmiere·Paul Letourneau·James R Bamburg
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Abstract

The regulation of filopodial dynamics by neurotrophins and other guidance cues plays an integral role in growth cone pathfinding. Filopodia are F-actin-based structures that explore the local environment, generate forces and play a role in growth cone translocation. Here, we review recent research showing that the actin-depolymerizing factor (ADF)/cofilin family of proteins mediates changes in the length and number of growth cone filopodia in response to brain-derived neurotrophic factor (BDNF). Although inhibition of myosin contractility also causes filopodial elongation, the elongation in response to BDNF does not occur through a myosin-dependent pathway. Active ADF/cofilin increases the rate of cycling between the monomer and polymer pools and is critical for the BDNF-induced changes. Thus, we discuss potential mechanisms by which ADF/cofilin may affect filopodial initiation and length change via its effects on F-actin dynamics in light of past research on actin and myosin function in growth cones.

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Actin Depolymerizing FactorsAnimalsCell Line, TumorDestrinGrowth ConesHumansMiceMicrofilament ProteinsNerve Tissue ProteinsJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, Non-P.H.S.Research Support, U.S. Gov't, P.H.S.Review

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Joseph Fass, Scott Gehler, Patrick Sarmiere, Paul Letourneau, James R Bamburg. 2004. Regulating filopodial dynamics through actin-depolymerizing factor/cofilin.. https://doi.org/10.1111/j.1447-073x.2004.00087.x

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