Isolation and molecular characterization of the COP1 gene homolog from rice, Oryza sativa L. subsp. Indica var. Pusa Basmati 1.

The COP1 (CONSTITUTIVE PHOTOMORPHOGENIC 1) gene has been identified earlier from dicot species namely Arabidopsis, tomato and pea. The protein encoded by this gene acts as a molecular switch that negatively regulates the transition from the skotomorphogenic to the photomorphogenic mode of plant development. We have isolated and characterized the COP1 homolog from a monocot species, i.e. rice (var. Pusa Basmati 1). All the functional domains (Zn-binding RING finger motif, coiled-coil region, WD-40 repeats, cytoplasmic/nuclear localization sequences and protein-protein interaction domains) that are known in the COP1 proteins from dicots are conserved in COP1 from rice as well. The transcript levels of COP1 vary in various tissues of the rice plant. These variations were found to be development-dependent and do not solely depend on the light conditions.