MIR1868 negatively regulates rice cold tolerance at both the seedling and booting stages

• DOI: 10.1016/j.cj.2024.02.005
• Publication Date: 2024-03-13T16:46:58Z
• Authors: Yang Shen; Xiaoxi Cai; Yan Wang; Wanhong Li; Dongpeng Li; Hao Wu; Weifeng Dong; Bowei Jia; Mingzhe Sun; Xiaoli Sun
• Keywords: 0301 basic medicine; 03 medical and health sciences; ROS scavenging; S; Agriculture (General); Agriculture; Rice; Cold tolerance; Soluble sugar accumulation; miRNA; S1-972

Low temperature causes rice yield losses of up to 30%–40%, therefore increasing its cold tolerance is a breeding target. Few genes in rice are reported to confer cold tolerance at both the vegetative and reproductive stages. This study revealed a rice-specific 24-nt miRNA, miR1868, whose accumulation was suppressed by cold stress. Knockdown of MIR1868 increased seedling survival, pollen fertility, seed setting, and grain yield under cold stress, whereas its overexpression conferred the opposite phenotype. Knockdown of MIR1868 increased reactive oxygen species (ROS) scavenging and soluble sugar content under cold stress by increasing the expression of peroxidase genes and sugar metabolism genes, and its overexpression produced the opposite effect. Thus, MIR1868 negatively regulated rice cold tolerance via ROS scavenging and sugar accumulation.