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)
NPR3 is a target of miR1850.1.
Rice-specific miR1850.1 targets NPR3 to regulate cold stress response
Paper
2025
Plant Communications |
DOI
Background
Cold stress limits temperate rice production, causing severe yield losses. This study identifies the rice-specific microRNA miR1850.1 as a negative regulator of cold tolerance. Cold stress downregulates pri-miR1850 and mature miR1850.1/2, relieving miR1850.1-mediated repression of NPR3. miR1850.1 directly targets NPR3 3′ UTR, triggering transcript cleavage and likely translational repression. NPR3 is cold-induced and positively regulates tolerance at seedling and booting stages. The miR1850.1–NPR3 module also affects blast resistance and grain yield, offering targets for breeding cold-tolerant japonica rice.
Key Findings
Cold stress downregulates rice-specific pri-miR1850 and its mature products miR1850.1 and miR1850.2. Gain- and loss-of-function lines show that pri-miR1850 and miR1850.1 negatively regulate cold tolerance at both young-seedling and booting stages; miR1850.2 appears dispensable. miR1850.1 binds NPR3 3′ UTR at target site 1, mediating mRNA cleavage and reducing NPR3 transcript and protein levels. Cold stress induces NPR3 transcription and protein accumulation by alleviating miR1850.1 repression. NPR3 knockout decreases cold tolerance, whereas NPR3 overexpression enhances survival, pollen fertility, and seed setting under cold. Genetic analysis demonstrates that miR1850 functions through NPR3: pri-miR1850 overexpression or STTM1850.1 in NPR3-KO backgrounds no longer alters cold tolerance. The miR1850.1–NPR3 module also modulates rice blast resistance and grain yield, revealing a growth–defense–cold tolerance trade-off network.
Contribution
Creative Biogene supplied the pCAMBIA3301 vector (VET1427, USA), which served as the backbone for pri-miR1850 overexpression and related transgenic constructs. This material enabled gain-of-function assays in rice and supported validation of the miR1850.1–NPR3 regulatory module in cold tolerance, disease resistance, and yield.
Cold stress limits temperate rice production, causing severe yield losses. This study identifies the rice-specific microRNA miR1850.1 as a negative regulator of cold tolerance. Cold stress downregulates pri-miR1850 and mature miR1850.1/2, relieving miR1850.1-mediated repression of NPR3. miR1850.1 directly targets NPR3 3′ UTR, triggering transcript cleavage and likely translational repression. NPR3 is cold-induced and positively regulates tolerance at seedling and booting stages. The miR1850.1–NPR3 module also affects blast resistance and grain yield, offering targets for breeding cold-tolerant japonica rice.
Key Findings
Cold stress downregulates rice-specific pri-miR1850 and its mature products miR1850.1 and miR1850.2. Gain- and loss-of-function lines show that pri-miR1850 and miR1850.1 negatively regulate cold tolerance at both young-seedling and booting stages; miR1850.2 appears dispensable. miR1850.1 binds NPR3 3′ UTR at target site 1, mediating mRNA cleavage and reducing NPR3 transcript and protein levels. Cold stress induces NPR3 transcription and protein accumulation by alleviating miR1850.1 repression. NPR3 knockout decreases cold tolerance, whereas NPR3 overexpression enhances survival, pollen fertility, and seed setting under cold. Genetic analysis demonstrates that miR1850 functions through NPR3: pri-miR1850 overexpression or STTM1850.1 in NPR3-KO backgrounds no longer alters cold tolerance. The miR1850.1–NPR3 module also modulates rice blast resistance and grain yield, revealing a growth–defense–cold tolerance trade-off network.
Contribution
Creative Biogene supplied the pCAMBIA3301 vector (VET1427, USA), which served as the backbone for pri-miR1850 overexpression and related transgenic constructs. This material enabled gain-of-function assays in rice and supported validation of the miR1850.1–NPR3 regulatory module in cold tolerance, disease resistance, and yield.