pCAMBIA3301

Cold stress is a major limiting factor in temperate rice cultivation, causing significant yield losses. The researchers investigated the role of the rice-specific pri-miR1850 and its mature products, miR1850.1 and miR1850.2, in cold-stress responses. Using overexpression, artificial miRNA (amiRNA), and short tandem target mimic (STTM)-mediated knockdown approaches with Creative Biogene's pCAMBIA3301 and pCAMBIA1300 vectors, they demonstrated that pri-miR1850 and miR1850.1 negatively regulate cold tolerance at both seedling and booting stages by targeting the immune-related gene NPR3. Cold treatment relieved miR1850.1-mediated repression, resulting in increased NPR3 transcript and protein levels. Functional analyses including 5′ RACE and dual-luciferase assays confirmed direct targeting of NPR3 by miR1850.1, revealing a regulatory module that coordinates cold-stress response, disease resistance, and grain yield in rice.

Figure 1. Dual-luciferase assays and FLAG-NPR3 immunoblots showed that miR1850.1 directly cleaves NPR3 transcripts and suppresses its protein expression, while knockdown of miR1850.1 relieves this repression under cold stress. (Shen Y, et al., 2025)