Jumonji C Domain-Containing Protein OsJMJ712 Integrates Epigenetic Regulation and Circadian Clock to Fine-Tune Flowering in Rice

The Jumonji C domain-containing (JmjC) histone demethylases (JMJs) are involved in various aspects of plant development and responses to environmental changes. AtJMJs have been extensively studied in Arabidopsis for their roles in regulating flowering time, while their functions and molecular mechanisms in regulating flowering time in rice remain underexplored. Here, we demonstrate that the JmjC domain-only group member OsJMJ712 regulates heading date in rice. OsJMJ712 exhibits H3K36me3 demethylase activity on Ehd1 and RFT1 , and represses the expression of Ehd1 , Hd3a , and RFT1 . Furthermore, loss function of OsJMJ712 disrupts the circadian clock, and OsLHY directly binds to the promoter of OsJMJ712 to suppress its expression. These findings uncover that OsJMJ712 integrates histone demethylation and the circadian clock to fine-tune photoperiodic flowering in rice, providing new insights into the epigenetic control of photoperiodic flowering in crops.