title: Cortical regulation of cell size by a sizer cdr2p.
abstract: Cells can, in principle, control their size by growing to a specified size before commencing cell division. How any cell actually senses its own size remains poorly understood. The fission yeast Schizosaccharomyces pombe are rod-shaped cells that grow to ∼14 µm in length before entering mitosis. In this study, we provide evidence that these cells sense their surface area as part of this size control mechanism. We show that cells enter mitosis at a certain surface area, as opposed to a certain volume or length. A peripheral membrane protein kinase cdr2p has properties of a dose-dependent 'sizer' that controls mitotic entry. As cells grow, the local cdr2p concentration in nodes at the medial cortex accumulates as a measure of cell surface area. Our findings, which challenge a previously proposed pom1p gradient model, lead to a new model in which cells sense their size by using cdr2p to probe the surface area over the whole cell and relay this information to the medial cortex. DOI: http://dx.doi.org/10.7554/eLife.02040.001.
authors.affiliation: Department of Microbiology and Immunology, Columbia University College of Physicians and Surgeons, New York, United States.
authors.forename: Kally Z
authors.initials: KZ
authors.lastname: Pan
authors.forename: Timothy E
authors.initials: TE
authors.lastname: Saunders
authors.forename: Ignacio
authors.initials: I
authors.lastname: Flor-Parra
authors.forename: Martin
authors.initials: M
authors.lastname: Howard
authors.forename: Fred
authors.initials: F
authors.lastname: Chang
mesh_terms: D048429:Cell Size; D011485:Protein Binding; D011494:Protein Kinases / Q000378:metabolism / Q000502:physiology*; D029702:Schizosaccharomyces pombe Proteins / Q000378:metabolism / Q000502:physiology*
chemical_list: D029702:Schizosaccharomyces pombe Proteins; D011494:Protein Kinases
keywords: cell cycle; cell size control; plasma membrane; protein kinase