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bioRxiv · 10.1101/2024.01.17.575521

Drosophila Asap regulates cellular protrusions via dArf6-dependent actin regulatory pathway

Kushwaha, S.·Mallik, B.·Mushtaq, Z.·Bisht, A.·Kumar, V.
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Abstract

Membrane protrusions are fundamental to cellular functions like migration, adhesion, and communication and depend upon the dynamic reorganization of the cytoskeleton. The GAP-dependent GTP hydrolysis of Arf proteins regulates actin-dependent membrane remodeling. Here, we show that the dAsap regulates membrane protrusions in S2R+ cells by a mechanism that critically relies on its ArfGAP domain and re-localization of actin regulators, SCAR, and Ena. While our data reinforce the preference of dAsap for Arf1 GTP hydrolysis in vitro, we demonstrate that induction of membrane protrusions in S2R+ cells depends on Arf6 inactivation. This study furthers our understanding of how dAsap-dependent GTP hydrolysis maintains a balance between active and inactive states of dArf6 to regulate cell shape.

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Kushwaha, S., Mallik, B., Mushtaq, Z., Bisht, A., Kumar, V.. 2024-01-17. Drosophila Asap regulates cellular protrusions via dArf6-dependent actin regulatory pathway. https://doi.org/10.1101/2024.01.17.575521

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