Synergy between Wsp1 and Dip1 may initiate assembly of endocytic actin networks
- University of Oregon, United States
- Upstate Medical University, United States
- University of Washington, United States
Abstract
The actin filament nucleator Arp2/3 complex is activated at cortical sites in S. pombe to assemble branched actin networks that drive endocytosis. Arp2/3 complex activators Wsp1 and Dip1 are required for proper actin assembly at endocytic sites, but how they coordinately control Arp2/3-mediated actin assembly is unknown. Alone, Dip1 activates Arp2/3 complex without preexisting actin filaments to nucleate 'seed' filaments that activate Wsp1-bound Arp2/3 complex, thereby initiating branched actin network assembly. In contrast, because Wsp1 requires pre-existing filaments to activate, it has been assumed to function exclusively in propagating actin networks by stimulating branching from pre-existing filaments. Here we show that Wsp1 is important not only for propagation, but also for initiation of endocytic actin networks. Using single molecule TIRF microscopy we show that Wsp1 synergizes with Dip1 to co-activate Arp2/3 complex. Synergistic coactivation does not require pre-existing actin filaments, explaining how Wsp1 contributes to actin network initiation in cells.
Data availability
All data generated and analyzed in this study have been included in the manuscript and supporting source data files. An individual source data file has been provided for Figures 1, 2, 3 and 4.
Article and author information
Author details
Funding
National Institute of General Medical Sciences (R35GM136319)
- Brad J Nolen
National Institute of General Medical Sciences (GM007759)
- Connor John Balzer
- Luke A Helgeson
American Heart Association (18PRE33960110)
- Connor John Balzer
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2020, Balzer 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.
Metrics
-
- 1,428
- views
-
- 176
- downloads
-
- 8
- citations
Views, downloads and citations are aggregated across all versions of this paper published by eLife.
Citations by DOI
-
- 8
- citations for umbrella DOI https://doi.org/10.7554/eLife.60419
Download links
A two-part list of links to download the article, or parts of the article, in various formats.
Downloads (link to download the article as PDF)
Open citations (links to open the citations from this article in various online reference manager services)
Cite this article (links to download the citations from this article in formats compatible with various reference manager tools)
Synergy between Wsp1 and Dip1 may initiate assembly of endocytic actin networks
eLife 9:e60419.
https://doi.org/10.7554/eLife.60419
