Abstract
In higher plants, many biological processes are rhythmically controlled through the circadian clock. For the model plant Arabidopsis thaliana, a certain number of genes that encode clock-associated genes (e.g., CCA1/LHY, ELF4) were already reported. A set of pseudo-response regulators (PRRs), including PRR1/TOC1, also play essential roles close to the central oscillator. On the other hand, recent results from plant genomics made it possible to conduct a comparative genomics with other model plants. Based on this idea, in the hope of understanding the clock function in the crop, Oryza sativa, here we intensively inspected a set of rice genes, which appear to be orthologous to the well-documented Arabidopsis clock-associated genes (e.g., OsTOC1, OsPRRs, OsCCA1, OsZTL, OsLUX). The results showed that certain clock-associated genes are highly conserved both in the dicot and monocot. The results will also be discussed with reference to the conserved clock mechanism in higher plants.
