title: Overexpression of lalA, a paralog of labA, is capable of affecting both circadian gene expression and cell growth in the cyanobacterium Synechococcus elongatus PCC 7942.
abstract: In the cyanobacterium Synechococcus elongatus, LabA negatively regulates circadian gene expression under the control of Kai-protein-based clock. Here we conducted a molecular genetic analysis of lalA, a paralog of labA. Although a lalA loss of function mutant did not exhibit any apparent phenotype under our experimental conditions, lalA overexpression inhibited cell growth and decreased cell viability. Moderate lalA overexpression brought about abnormalities in circadian gene expression: reduced amplitude of kaiBC expression rhythm, and altered peak and trough timing of psbAI and kaiA expression rhythms. These results imply that lalA is capable of affecting circadian gene expression and cell growth.
authors.affiliation: Division of Biological Science, Graduate School of Science, Nagoya University, Nagoya 464-8602, Japan.
authors.forename: Yasuhito
authors.initials: Y
authors.lastname: Taniguchi
authors.forename: Tomoe
authors.initials: T
authors.lastname: Nishikawa
authors.forename: Takao
authors.initials: T
authors.lastname: Kondo
authors.forename: Tokitaka
authors.initials: T
authors.lastname: Oyama
mesh_terms: D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000145:classification / Q000235:genetics / Q000378:metabolism*; D001683:Biological Clocks / Q000502:physiology*; D002940:Circadian Rhythm / Q000502:physiology*; D015964:Gene Expression Regulation, Bacterial; D008969:Molecular Sequence Data; D010802:Phylogeny; D016415:Sequence Alignment; D046940:Synechococcus / Q000166:cytology / Q000235:genetics* / Q000502:physiology*
chemical_list: D001426:Bacterial Proteins