Abstract
In Arabidopsis thaliana, many biological processes are rhythmically controlled through the circadian clock, which is also involved in the photoperiodic control of flowering time that is regulated by the downstream factors such as CO and FT. We previously proposed that the pseudo-response regulators (PRR3, PRR5, PRR7, PRR9), including PRR1/TOC1, play essential roles close to the central oscillator. As the result, misexpressions and/or mutational lesions of any one of these genes result in a marked phenotype of flowering time. To gain insight into this particular issue, here we characterized certain prr multiple mutants with reference to the expression of the flowering genes, CO and FT. To see a link with the light signal transduction, a red-light photoreceptor mutant (phyB) was also integrated into such genetic analyses. Together with morphological characteristics of these prr mutants, the results will be discussed about the link between the PRR clock function(s) and the photosignal-dependent flowering.
