title: A cellulose synthase-like protein involved in hyphal tip growth and morphological differentiation in streptomyces.
abstract: Cellulose synthase and cellulose synthase-like proteins, responsible for synthesizing beta-glucan-containing polysaccharides, play a fundamental role in cellular architectures, such as plant cell and tissue morphogenesis, bacterial biofilm formation, and fruiting-body development. However, the roles of the proteins involved in the developmental process are not well understood. Here, we report that a cellulose synthase-like protein (CslA(Sc)) in Streptomyces has a function in hyphal tip growth and morphological differentiation. The cslA(Sc) replacement mutant showed pleiotropic defects, including the severe delay of aerial-hyphal formation and altered cell wall morphology. Calcofluor white fluorescence analysis demonstrated that polysaccharide synthesis at hyphal tips was dependent on CslA(Sc). cslA(Sc) was constitutively transcribed, and an enhanced green fluorescent protein-CslA(Sc) fusion protein was mostly located at the hyphal tips. An extract enriched in morphogenetic chaplin proteins promoted formation of aerial hyphae by the mutant. Furthermore, a two-hybrid experiment indicated that the glycosyltransferase domain of CslA(Sc) interacted with the tropomyosin-like polarity-determining DivIVA protein, suggesting that the tip-located DivIVA governed tip recruitment of the CslA(Sc) membrane protein. These results imply that the cellulose synthase-like protein couples extracellular and cytoskeletal components functioning in tip growth and cell development.
authors.affiliation: State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, China.
authors.forename: Hongbin
authors.initials: H
authors.lastname: Xu
authors.forename: Keith F
authors.initials: KF
authors.lastname: Chater
authors.forename: Zixin
authors.initials: Z
authors.lastname: Deng
authors.forename: Meifeng
authors.initials: M
authors.lastname: Tao
mesh_terms: D000595:Amino Acid Sequence; D019677:Artificial Gene Fusion; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D018797:Cell Cycle Proteins / Q000378:metabolism; D017353:Gene Deletion; D020869:Gene Expression Profiling; D023061:Gene Order; D017930:Genes, Reporter; D005964:Glucosyltransferases / Q000235:genetics / Q000378:metabolism*; D049452:Green Fluorescent Proteins / Q000032:analysis / Q000235:genetics; D008853:Microscopy; D008855:Microscopy, Electron, Scanning; D046529:Microscopy, Electron, Transmission; D008969:Molecular Sequence Data; D016254:Mutagenesis, Insertional; D011135:Polysaccharides, Bacterial / Q000096:biosynthesis; D011485:Protein Binding; D016415:Sequence Alignment; D048372:Streptomyces coelicolor / Q000737:chemistry / Q000166:cytology* / Q000201:enzymology* / Q000235:genetics; D020798:Two-Hybrid System Techniques
chemical_list: D001426:Bacterial Proteins; D018797:Cell Cycle Proteins; C104636:DivIVA protein, bacteria; D011135:Polysaccharides, Bacterial; C485184:enhanced green fluorescent protein; D049452:Green Fluorescent Proteins; D005964:Glucosyltransferases; C478648:cellulose synthase