Abstract
Photosynthesis affects crop growth and yield. The roles of microRNAs (miRNAs) in photosynthesis are little known. In the present study, the role of the OsNF-YB7–OsMIR5810–OsMRLP6 regulatory module in photosynthesis was investigated. The malectin-like protein gene OsMRLP6 was identified as a target gene of osa-miR5810 (miR5810). Overexpression in rice of miR5810 or down-expression of OsMRLP6 resulted in reduced expression of genes involved in chloroplast development and photosynthesis and decreased net photosynthetic rate, finally leading to lower shoot biomass and grain yield. Down-expression of miR5810 and overexpression of OsMRLP6 showed the opposite effect. Overexpression of transcription factor OsNF-YB7 elevated expression of OsMIR5810 in rice seedlings by binding to its promoter. The OsNF-YB7–OsMIR5810–OsMRLP6 regulatory module affects photosynthesis to mediate growth and grain yield.