Rice B2 and B3 RAFs play central roles in both ABA and osmotic stress signaling

Rice (Oryza sativa L.) is one of the most important crops worldwide. In the field, rice always faces low humidity, salinity, or drought in various growth stages, which largely limit seedling growth, tillering, filling, and yield of rice. Here, we generated B RAF high-order mutants by CRISPR/Cas9 mediated genome editing. By RNA-seq analysis, we found rice B2 and B3 RAFs play central roles in osmotic stress responses, the mannitol-induced expression genes are largely impaired. Our findings uncovered the central role of B2 and B3 RAFs in rice's osmotic stress responses and ABA signaling. To investigate the impact of B2 and B3 RAFs on osmotic stress-induced gene expression in rice, we performed a transcriptomics analysis in WT/NIP and raf-b2/3 seedlings with or without 6 hours of 800 mM mannitol treatments. Total RNA was isolated from 5-day-old seedlings of WT/NIP and raf-b2/3 mutant with and without mannitol treatment, and library preparation. All libraries were sequenced in paired-end 150 bases protocol (PE150) on an Illumina Nova sequencer.