Overexpression of Os ERF 48 causes regulation of Os CML 16 , a calmodulin‐like protein gene that enhances root growth and drought tolerance

作者：Harin Jung, Pil Joong Chung, Su Hyun Park, Mark Christian Felipe R. Redillas, Youn Shic Kim, Joo‐Won Suh, Ju‐Kon Kim · 发表于：Plant Biotechnology Journal · 年份：2017 · DOI：10.1111/pbi.12716 · 被引用次数：207 · 研究领域：Plant nutrient uptake and metabolism、Plant Molecular Biology Research、Photosynthetic Processes and Mechanisms

Summary The AP 2/ ERF family is a plant‐specific transcription factor family whose members have been associated with various developmental processes and stress tolerance. Here, we functionally characterized the drought‐inducible Os ERF 48 , a group Ib member of the rice ERF family with four conserved motifs, CMI ‐1, ‐2, ‐3 and ‐4. A transactivation assay in yeast revealed that the C‐terminal CMI ‐1 motif was essential for Os ERF 48 transcriptional activity. When Os ERF 48 was overexpressed in an either a root‐specific ( ROX O s ERF 48 ) or whole‐body ( OX O s ERF 48 ) manner, transgenic plants showed a longer and denser root phenotype compared to the nontransgenic ( NT ) controls. When plants were grown on a 40% polyethylene glycol‐infused medium under in vitro drought conditions, ROX O s ERF 48 plants showed a more vigorous root growth than OX O s ERF 48 and NT plants. In addition, the ROX O s ERF 48 plants exhibited higher grain yield than OX O s ERF 48 and NT plants under field‐drought conditions. We constructed a putative Os ERF 48 regulatory network by cross‐referencing ROX O s ERF 48 root‐specific RNA ‐seq data with a co‐expression network database, from which we inferred the involvement of 20 drought‐related genes in Os ERF 48 ‐mediated responses. These included genes annotated as being involved in stress signalling, carbohydrate metabolism, cell‐wall proteins and drought responses. They included, Os CML 16 , a key gene in calcium signalling during abiotic stress, whic...