STOP1 Regulates Multiple Genes That Protect Arabidopsis from Proton and Aluminum Toxicities

作者：Yoshiharu Sawaki, Satoshi Iuchi, Yasufumi Kobayashi, Yuriko Kobayashi, Takashi Ikka, Nozomu Sakurai, Miki Fujita, Kazuo Shinozaki, Daisuke Shibata, Masatomo Kobayashi, Hiroyuki Koyama · 发表于：PLANT PHYSIOLOGY · 年份：2009 · DOI：10.1104/pp.108.134700 · 被引用次数：362 · 研究领域：Aluminum toxicity and tolerance in plants and animals、Plant Micronutrient Interactions and Effects、Plant Stress Responses and Tolerance

The Arabidopsis (Arabidopsis thaliana) mutant stop1 (for sensitive to proton rhizotoxicity1) carries a missense mutation at an essential domain of the histidine-2-cysteine-2 zinc finger protein STOP1. Transcriptome analyses revealed that various genes were down-regulated in the mutant, indicating that STOP1 is involved in signal transduction pathways regulating aluminum (Al)- and H(+)-responsive gene expression. The Al hypersensitivity of the mutant could be caused by down-regulation of AtALMT1 (for Arabidopsis ALUMINUM-ACTIVATED MALATE TRANSPORTER1) and ALS3 (ALUMINUM-SENSITIVE3). This hypothesis was supported by comparison of Al tolerance among T-DNA insertion lines and a transgenic stop mutant carrying cauliflower mosaic virus 35SAtALMT1. All T-DNA insertion lines of STOP1, AtALMT1, and ALS3 were sensitive to Al, but introduction of cauliflower mosaic virus 35SAtALMT1 did not completely restore the Al tolerance of the stop1 mutant. Down-regulation of various genes involved in ion homeostasis and pH-regulating metabolism in the mutant was also identified by microarray analyses. CBL-INTERACTING PROTEIN KINASE23, regulating a major K(+) transporter, and a sulfate transporter, SULT3;5, were down-regulated in the mutant. In addition, integral profiling of the metabolites and transcripts revealed that pH-regulating metabolic pathways, such as the gamma-aminobutyric acid shunt and biochemical pH stat pathways, are down-regulated in the mutant. These changes could explain the H(+)...