Rice microRNA171f/SCL6 module enhances drought tolerance by regulation of flavonoid biosynthesis genes
Taeyoung Um,
Joohee Choi,
Taehyeon Park,
Pil Joong Chung,
Se Eun Jung,
Jae Sung Shim,
Youn Shic Kim,
Ik‐Young Choi,
Soo Chul Park,
Se‐Jun Oh,
Jun Sung Seo,
Ju‐Kon Kim
Affiliations
Taeyoung Um
Graduate School of International Agricultural Technology and Crop Biotechnology Institute/GreenBio Science and Technology Seoul National University Pyeongchang South Korea
Joohee Choi
Graduate School of International Agricultural Technology and Crop Biotechnology Institute/GreenBio Science and Technology Seoul National University Pyeongchang South Korea
Taehyeon Park
Graduate School of International Agricultural Technology and Crop Biotechnology Institute/GreenBio Science and Technology Seoul National University Pyeongchang South Korea
Pil Joong Chung
Graduate School of International Agricultural Technology and Crop Biotechnology Institute/GreenBio Science and Technology Seoul National University Pyeongchang South Korea
Se Eun Jung
Graduate School of International Agricultural Technology and Crop Biotechnology Institute/GreenBio Science and Technology Seoul National University Pyeongchang South Korea
Jae Sung Shim
Graduate School of International Agricultural Technology and Crop Biotechnology Institute/GreenBio Science and Technology Seoul National University Pyeongchang South Korea
Youn Shic Kim
Graduate School of International Agricultural Technology and Crop Biotechnology Institute/GreenBio Science and Technology Seoul National University Pyeongchang South Korea
Ik‐Young Choi
Department of Agricultural and life industry Kangwon National University Chuncheon South Korea
Soo Chul Park
Graduate School of International Agricultural Technology and Crop Biotechnology Institute/GreenBio Science and Technology Seoul National University Pyeongchang South Korea
Se‐Jun Oh
LaSemilla Co. Ltd Pyeongchang South Korea
Jun Sung Seo
Graduate School of International Agricultural Technology and Crop Biotechnology Institute/GreenBio Science and Technology Seoul National University Pyeongchang South Korea
Ju‐Kon Kim
Graduate School of International Agricultural Technology and Crop Biotechnology Institute/GreenBio Science and Technology Seoul National University Pyeongchang South Korea
Abstract Plants have evolved sophisticated defense systems to enhance drought tolerance. These include the microRNA (miRNA) group of small noncoding RNAs that act as post‐transcriptional regulators; however, details of the mechanisms by which they confer drought tolerance are not well understood. Here, we show that osa‐MIR171f, a member of osa‐MIR171 gene family, is mainly expressed in response to drought stress and regulates the transcript levels of SCARECROW‐LIKE6‐I (SCL6‐I) and SCL6‐II in rice (Oryza sativa). The SCL6 genes are known to be involved in shoot branching and flag leaf morphology. Osa‐MIR171f‐overexpressing (osa‐MIR171f‐OE) transgenic plants showed reduced drought symptoms compared with non‐transgenic (NT) control plants under both field drought and polyethylene glycol (PEG)‐mediated dehydration stress conditions. Transcriptome analysis of osa‐MIR171f‐OE plants and osa‐mir171f‐knockout (K/O) lines generated by clustered regularly interspaced short palindromic repeats (CRISPR/Cas9) revealed that osa‐mature‐miR171a‐f (osa‐miR171) regulates the expression of flavonoid biosynthesis genes, consequently leading to drought tolerance. This upregulation in the osa‐MIR171f‐OE plants, which did not occur in NT control plants, was observed under both normal and drought conditions. Our findings indicate that osa‐miR171 plays a role in drought tolerance by regulating SCL6‐I and SCL6‐II transcript levels.
