Abstract
Cellular asymmetry begins with the selection of a discrete point on the cell surface that triggers Rho-GTPases activation and localized assembly of the cytoskeleton to establish new growth zones. The cylindrical shape of fission yeast is organized by microtubules (MT) that deliver the landmark Tea1-Tea4 complex at the cell tips to define the growth poles. However, only a few tea1Δ cells mistaken the direction of growth, indicating that they manage to detect their growth sites. Here, we show that Rgf1 (Rho1-GEF) and Tea4 are components of the same complex and that Rgf1 activity toward Rho1 is required for strengthen Tea4 at the cell tips. Moreover, in cells lacking Tea1, selection of the correct growth site depends on Rgf1 and on a correctly polarized actin cytoskeleton, both necessary for Rho1 activation at the pole. We propose an actin-dependent mechanism driven by Rgf1-Rho1 that marks the poles independently of MTs and the Tea1-Tea4 complex.
Copyright: © 2024 Garcia et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
MeSH terms
-
Actins* / metabolism
-
Cell Polarity / physiology
-
Guanine Nucleotide Exchange Factors / genetics
-
Guanine Nucleotide Exchange Factors / metabolism
-
Microtubule-Associated Proteins
-
Microtubules* / metabolism
-
Schizosaccharomyces pombe Proteins* / genetics
-
Schizosaccharomyces pombe Proteins* / metabolism
-
Schizosaccharomyces* / genetics
-
Schizosaccharomyces* / growth & development
-
Schizosaccharomyces* / metabolism
-
Signal Transduction
-
rho GTP-Binding Proteins* / genetics
-
rho GTP-Binding Proteins* / metabolism
Substances
-
Schizosaccharomyces pombe Proteins
-
rho GTP-Binding Proteins
-
Actins
-
Tea4 protein, S pombe
-
Tea1 protein, S pombe
-
Guanine Nucleotide Exchange Factors
-
Microtubule-Associated Proteins
Grants and funding
This work was supported by a grant PID2020-115111GB-I00 (Ministerio de Ciencia e Innovación, MICINN, Spain) to Y.S. The PhD fellowship (FPU program) from Ministerio de Ciencia e Innovación, MICINN, Spain supported RC. The Universidad de Salamanca postdoctoral fellowship (Programa II) supported PG. A contract obtained through the Consejería de Educación de la Junta de Castilla y León was granted to TE. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.