ERK3/MAPK6 dictates CDC42/RAC1 activity and ARP2/3-dependent actin polymerization
The actin cytoskeleton is tightly controlled by RhoGTPases, actin binding-proteins and nucleation-promoting factors to perform fundamental cellular functions. We have previously shown that ERK3, an atypical MAPK controls IL-8 production and chemotaxis52. Here, we show in human cells that, ERK3 directly acts as a guanine nucleotide exchange factor for CDC42and phosphorylates the ARP3 subunit of the ARP2/3 complex at S418 to promote filopodia formation and actin polymerization, respectively. Consistently, depletion of ERK3 prevented both basal and EGF-dependent RAC1 and CDC42 activation, maintenance of F-actin content, filopodia formation and epithelial cell migration. Further, ERK3 protein bound directly to the purified ARP2/3 complex and augmented polymerization of actin in vitro. ERK3 kinase activity was required for the formation of actin-rich protrusions in mammalian cells. These findings unveil a fundamentally unique pathway employed by cells to control actin-dependent cellular functions.
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Article and author information
Else Kröner-Fresenius-Stiftung (SUN-MAPK)
- Katarzyna Bogucka-Janczi
- Gregory Harms
Deutsche Forschungsgemeinschaft (CRC1292)
- Katarzyna Bogucka-Janczi
- Krishnaraj Rajalingam
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Animal experimentation: The animal experiments were performed as per the guideliens of University MEdical center Basel
- Volker Dötsch, Goethe University, Germany
- Preprint posted: October 13, 2022 (view preprint)
- Received: November 29, 2022
- Accepted: April 13, 2023
- Accepted Manuscript published: April 14, 2023 (version 1)
- Accepted Manuscript updated: April 17, 2023 (version 2)
- Version of Record published: May 17, 2023 (version 3)
© 2023, Bogucka-Janczi et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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