miR827 orchestrates the regulation of SPX‐MFS1 and SPX‐MFS5 with the assistance of lncRNA767 to enhance phosphate starvation tolerance and maize development

Summary MicroRNA827 (miR827) is functionally conserved among different plant species and displays species‐specific characteristics, but the mechanisms by which miR827 regulates phosphate (Pi) starvation tolerance and maize development remain elusive. We found that miR827 selectively targets the Pi transporter genes SPX‐MFS1 and SPX‐MFS5 . miR827 overexpression improved the Pi starvation tolerance, plant architecture and grain yield and quality, whereas miR827 suppression yielded a contrasting phenotype. In addition, we identified a specific long noncoding RNA ( lncRNA767 ) that serves as a direct target and a facilitator of miR827 and can stabilize the SPX‐MFS1 and SPX‐MFS5 transcripts, leading to their translation inhibition. The orchestrated regulation of SPX‐MFS1 and SPX‐MFS5 modulates PHR1; 1 and PHR1; 2, which are critical transcription factors in Pi signalling, and thereby affects the expression of downstream Pi starvation‐induced genes. Together, these findings demonstrate that miR827, assisted by lncRNA767 , enhances SPX‐MFS1 and SPX‐MFS5 suppression and thus exerts a significant impact on Pi homeostasis and several essential agronomic traits of maize.