Paxillin-Mediated Recruitment of Calcineurin to the Contractile Ring Is Required for the Correct Progression of Cytokinesis in Fission Yeast
Rebeca Martín-García,
Victor Arribas,
Pedro M. Coll,
Mario Pinar,
Raul A. Viana,
Sergio A. Rincón,
Jaime Correa-Bordes,
Juan Carlos Ribas,
Pilar Pérez
Affiliations
Rebeca Martín-García
Instituto de Biología Funcional y Genómica, Consejo Superior de Investigaciones Científicas (CSIC) and Departamento de Microbiología y Genética, Universidad de Salamanca, Salamanca, Spain
Victor Arribas
Instituto de Biología Funcional y Genómica, Consejo Superior de Investigaciones Científicas (CSIC) and Departamento de Microbiología y Genética, Universidad de Salamanca, Salamanca, Spain
Pedro M. Coll
Instituto de Biología Funcional y Genómica, Consejo Superior de Investigaciones Científicas (CSIC) and Departamento de Microbiología y Genética, Universidad de Salamanca, Salamanca, Spain
Mario Pinar
Departamento de Biología Celular y Molecular, Centro de Investigaciones Biológicas del CSIC, Madrid 28040, Spain
Raul A. Viana
Instituto de Biología Funcional y Genómica, Consejo Superior de Investigaciones Científicas (CSIC) and Departamento de Microbiología y Genética, Universidad de Salamanca, Salamanca, Spain
Sergio A. Rincón
Institut Curie, PSL Research University, CNRS, UMR 144, 75005 Paris, France
Jaime Correa-Bordes
Departamento de Ciencias Biomédicas, Universidad de Extremadura, Badajoz, Spain
Juan Carlos Ribas
Instituto de Biología Funcional y Genómica, Consejo Superior de Investigaciones Científicas (CSIC) and Departamento de Microbiología y Genética, Universidad de Salamanca, Salamanca, Spain
Pilar Pérez
Instituto de Biología Funcional y Genómica, Consejo Superior de Investigaciones Científicas (CSIC) and Departamento de Microbiología y Genética, Universidad de Salamanca, Salamanca, Spain; Corresponding author
Summary: Paxillin is a scaffold protein that participates in focal adhesion signaling in mammalian cells. Fission yeast paxillin ortholog, Pxl1, is required for contractile actomyosin ring (CAR) integrity and collaborates with the β-glucan synthase Bgs1 in septum formation. We show here that Pxl1’s main function is to recruit calcineurin (CN) phosphatase to the actomyosin ring; and thus the absence of either Pxl1 or calcineurin causes similar cytokinesis defects. In turn, CN participates in the dephosphorylation of the Cdc15 F-BAR protein, which recruits and concentrates Pxl1 at the CAR. Our findings suggest the existence of a positive feedback loop between Pxl1 and CN and establish that Pxl1 is a crucial component of the CN signaling pathway during cytokinesis. : Martín-García et al. show that fission yeast paxillin binds and recruits calcineurin (CN) phosphatase to the cytokinetic actomyosin ring (CAR). There, CN collaborates with Bgs1 in septum ingression and promotes the concentration of Pxl1 at the CAR in a feedback loop likely mediated through CN dephosphorylation of the Cdc15 F-BAR protein, essential for cytokinesis. Keywords: Schizosaccharomyces pombe, cytokinesis, calcineurin, paxillin, septum, actomyosin ring, Bgs1, Cdc15
