Arf6 anchors Cdr2 nodes at the cell cortex to control cell size at division |
| |
| Authors: | Hannah E. Opalko Kristi E. Miller Hyun-Soo Kim Cesar Augusto Vargas-Garcia Abhyudai Singh Michael-Christopher Keogh James B. Moseley |
| |
| Affiliation: | 1. Department of Biochemistry and Cell Biology, the Geisel School of Medicine at Dartmouth, Hanover, NH ; 2. Department of Cell Biology, Albert Einstein College of Medicine, New York, NY ; 3. Grupo de Investigación en Sistemas Agropecuarios Sostenibles, Corporación Colombiana de Investigación Agropecuaria – AGROSAVIA, Bogotá, Colombia ; 4. Department of Electrical and Computer Engineering, University of Delaware, Newark, DE |
| |
| Abstract: | Fission yeast cells prevent mitotic entry until a threshold cell surface area is reached. The protein kinase Cdr2 contributes to this size control system by forming multiprotein nodes that inhibit Wee1 at the medial cell cortex. Cdr2 node anchoring at the cell cortex is not fully understood. Through a genomic screen, we identified the conserved GTPase Arf6 as a component of Cdr2 signaling. Cells lacking Arf6 failed to divide at a threshold surface area and instead shifted to volume-based divisions at increased overall size. Arf6 stably localized to Cdr2 nodes in its GTP-bound but not GDP-bound state, and its guanine nucleotide exchange factor (GEF), Syt22, was required for both Arf6 node localization and proper size at division. In arf6Δ mutants, Cdr2 nodes detached from the membrane and exhibited increased dynamics. These defects were enhanced when arf6Δ was combined with other node mutants. Our work identifies a regulated anchor for Cdr2 nodes that is required for cells to sense surface area. |
| |
| Keywords: | |
|
|
