Identification and functional characterization of the chloride channel gene, GsCLC-c2 from wild soybean

作者：Peipei Wei, Benning Che, Like Shen, Yiqing Cui, Shengyan Wu, Cong Cheng, Feng Liu, Man‐Wah Li, Bingjun Yu, Hon‐Ming Lam · 发表于：BMC Plant Biology · 年份：2019 · DOI：10.1186/s12870-019-1732-z · 被引用次数：97 · 研究领域：GABA and Rice Research、Soybean genetics and cultivation、Plant Stress Responses and Tolerance

The anionic toxicity of plants under salt stress is mainly caused by chloride (Cl − ). Thus Cl − influx, transport and their regulatory mechanisms should be one of the most important aspects of plant salt tolerance studies, but are often sidelined by the focus on sodium (Na + ) toxicity and its associated adaptations. Plant chloride channels (CLCs) are transport proteins for anions including Cl − and nitrate (NO 3 − ), and are critical for nutrition uptake and transport, adjustment of cellular turgor, stomatal movement, signal transduction, and Cl − and NO 3 − homeostasis under salt stress. Among the eight soybean CLC genes, the tonoplast-localized c2 has uniquely different transcriptional patterns between cultivated soybean N23674 and wild soybean BB52. Using soybean hairy root transformation, we found that GsCLC-c2 over-expression contributed to Cl − and NO 3 − homeostasis, and therefore conferred salt tolerance, through increasing the accumulation of Cl − in the roots, thereby reducing their transportation to the shoots where most of the cellular damages occur. Also, by keeping relatively high levels of NO 3 − in the aerial part of the plant, GsCLC-c2 could reduce the Cl − /NO 3 − ratio. Wild type GsCLC-c2, but not its mutants ( S184P , E227V and E294G ) with mutations in the conserved domains, is able to complement Saccharomyces cerevisiae △ gef1 Cl − sensitive phenotype. Using two-electrode voltage clamp on Xenopus laevis oocytes injected with GsCLC-c2 cRNA, we found tha...