title: Involvement of PpDof1 transcriptional repressor in the nutrient condition-dependent growth control of protonemal filaments in Physcomitrella patens.
abstract: In higher plants, the Dof transcription factors that harbour a conserved plant-specific DNA-binding domain function in the regulation of diverse biological processes that are unique to plants. Although these factors are present in both higher and lower plants, they have not yet been characterized in lower plants. Here six genes encoding Dof transcription factors in the moss Physcomitrella patens are characterized and two of these genes, PpDof1 and PpDof2, are functionally analysed. The targeted disruption of PpDof1 caused delayed or reduced gametophore formation, accompanied by an effect on development of the caulonema from the chloronema. Furthermore, the ppdof1 disruptants were found to form smaller colonies with a reduced frequency of branching of protonemal filaments, depending on the nutrients in the media. Most of these phenotypes were not apparent in the ppdof2 disruptant, although the ppdof2 disruptants also formed smaller colonies on a particular medium. Transcriptional repressor activity of PpDof1 and PpDof2 and modified expression of a number of genes in the ppdof disruptant lines were also shown. These results thus suggest that the PpDof1 transcriptional repressor has a role in controlling nutrient-dependent filament growth.
authors.affiliation: Department of Applied Biological Chemistry, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Yayoi 1-1-1, Bunkyo-ku, Tokyo 113-8657, Japan.
authors.forename: Takumi
authors.initials: T
authors.lastname: Sugiyama
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Ishida
authors.forename: Nobumitsu
authors.initials: N
authors.lastname: Tabei
authors.forename: Mikao
authors.initials: M
authors.lastname: Shigyo
authors.forename: Mineko
authors.initials: M
authors.lastname: Konishi
authors.forename: Tadakatsu
authors.initials: T
authors.lastname: Yoneyama
authors.forename: Shuichi
authors.initials: S
authors.lastname: Yanagisawa
mesh_terms: D000595:Amino Acid Sequence; D019068:Bryopsida / Q000166:cytology* / Q000187:drug effects / Q000235:genetics / Q000254:growth & development*; D003470:Culture Media / Q000494:pharmacology*; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D017343:Genes, Plant / Q000235:genetics; D055993:Germ Cells, Plant / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D008969:Molecular Sequence Data; D009154:Mutation / Q000235:genetics; D010940:Plant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D012097:Repressor Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D014158:Transcription, Genetic / Q000187:drug effects
chemical_list: D003470:Culture Media; D010940:Plant Proteins; D012097:Repressor Proteins