OsCOL16 Represses Flowering in Rice

Flowering time is an important agronomic trait which significantly affects yield potential for cereal crops. The CONSTANS (CO)-like gene family plays roles in the regulation of flowering time. CO-like proteins are divided into four phylogenetic groups in rice. While several genes from groups I, III, and IV have been characterized, little is known about the genes in group II in rice.

Weixun Wu, together with researchers from China National Rice Research Institute and the Chinese Academy of Agricultural Sciences, performed functional characterization of the constitutive floral inhibitor, OsCOL16 in rice. The gene encodes a group-II CO-like protein that delays flowering time and increases plant height and grain yield.

Overexpression of OsCOL16 resulted in late heading in both long-day and short-day conditions. The team also found that OsCOL16 upregulates the expression of the floral repressor Grain number plant height and heading date 7 (Ghd7), leading to downregulation of the expression of Early heading date 1, Heading date 3a, and RICE FLOWERING LOCUS T1, leading to late flowering.

Analyses revealed that OsCOL16 plays an important role in regulating rice photoperiodic flowering, allowing the rice plant to adapt to its environment.

For more on this study, read the article in Plant Science.