title: Changes in the oligomerization potential of the division inhibitor UgtP co-ordinate Bacillus subtilis cell size with nutrient availability.
abstract: How cells co-ordinate size with growth and development is a major, unresolved question in cell biology. In previous work we identified the glucosyltransferase UgtP as a division inhibitor responsible for increasing the size of Bacillus subtilis cells under nutrient-rich conditions. In nutrient-rich medium, UgtP is distributed more or less uniformly throughout the cytoplasm and concentrated at the cell poles and/or the cytokinetic ring. Under these conditions, UgtP interacts directly with FtsZ to inhibit division and increase cell size. Conversely, under nutrient-poor conditions, UgtP is sequestered away from FtsZ in punctate foci, and division proceeds unimpeded resulting in a reduction in average cell size. Here we report that nutrient-dependent changes in UgtP's oligomerization potential serve as a molecular rheostat to precisely co-ordinate B. subtilis cell size with nutrient availability. Our data indicate UgtP interacts with itself and the essential cell division protein FtsZ in a high-affinity manner influenced in part by UDP glucose, an intracellular proxy for nutrient availability. These findings support a model in which UDP-glc-dependent changes in UgtP's oligomerization potential shift the equilibrium between UgtP•UgtP and UgtP•FtsZ, fine-tuning the amount of FtsZ available for assembly into the cytokinetic ring and with it cell size.
authors.affiliation: Department of Biology, Washington University, St. Louis, MO 63130, USA. plevin@wustl.edu
authors.forename: An-Chun
authors.initials: AC
authors.lastname: Chien
authors.forename: Shannon Kian Gharabiklou
authors.initials: SK
authors.lastname: Zareh
authors.forename: Yan Mei
authors.initials: YM
authors.lastname: Wang
authors.forename: Petra Anne
authors.initials: PA
authors.lastname: Levin
mesh_terms: D001412:Bacillus subtilis / Q000166:cytology* / Q000201:enzymology* / Q000235:genetics / Q000378:metabolism; D001426:Bacterial Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D002455:Cell Division; D003470:Culture Media / Q000378:metabolism; D003598:Cytoskeletal Proteins / Q000235:genetics / Q000378:metabolism; D015964:Gene Expression Regulation, Bacterial; D005964:Glucosyltransferases / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D011485:Protein Binding; D014532:Uridine Diphosphate Glucose / Q000378:metabolism*
chemical_list: D001426:Bacterial Proteins; D003470:Culture Media; D003598:Cytoskeletal Proteins; C071525:FtsZ protein, Bacteria; D005964:Glucosyltransferases; D014532:Uridine Diphosphate Glucose