These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: The function of the clock-associated transcriptional regulator CCA1 (CIRCADIAN CLOCK-ASSOCIATED 1) in Arabidopsis thaliana.
    Author: Kawamura M, Ito S, Nakamichi N, Yamashino T, Mizuno T.
    Journal: Biosci Biotechnol Biochem; 2008 May; 72(5):1307-16. PubMed ID: 18460819.
    Abstract:
    In the model higher plant Arabidopsis thaliana, the CCA1 (CIRCADIAN CLOCK-ASSOCIATED 1) gene plays important circadian clock-associated roles. The CCA1 protein is a member of a small subfamily of single MYB-related transcription factors. This family consists of several homologous CCA1-like transcription factors, including the closest homolog LHY (LATE ELONGATED HYPOCOTYL). To gain insight into the molecular function of CCA1 and its homologs, here we took a unique genetic approach that was recently developed for Arabidopsis thaliana. Through this strategy, referred to as CRES-T (Chimeric REpressor Silencing Technology), a transgenic plant was constructed to produce a dominant negative transcriptional repressor (designated CCA1-SRDX). By employing the resulting transgenic lines, together with previously established cca1 lhy double mutant and CCA1-ox (over-expressing) plants, their circadian clock-associated phenotypes were examined and compared with each other. The observed clock-associated phenotypes of the CCA1-SRDX plants were very similar to those of CCA1-ox, but not to those of cca1 lhy, suggesting that CCA1 acts predominantly as a transcriptional repressor in nature. However, the developmental morphology (or architecture) of adult CCA1-SRDX plants were quite different from that of CCA1-ox, suggesting that CCA1 might also be implicated, directly or indirectly, in an as yet unknown circadian-associated output pathway at a late developmental stage.
    [Abstract] [Full Text] [Related] [New Search]