Dong Wei, Wang Yinghua, Takahashi Hideki
Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI 48824, USA.
Plants (Basel). 2019 Apr 18;8(4):103. doi: 10.3390/plants8040103.
Plant root system architecture changes drastically in response to availability of macronutrients in the soil environment. Despite the importance of root sulfur (S) uptake in plant growth and reproduction, molecular mechanisms underlying root development in response to S availability have not been fully characterized. We report here on the signaling module composed of the CLAVATA3 (CLV3)/EMBRYO SURROUNDING REGION (CLE) peptide and CLAVATA1 (CLV1) leucine-rich repeat receptor kinase, which regulate lateral root (LR) development in upon changes in S availability. The wild-type seedlings exposed to prolonged S deficiency showed a phenotype with low LR density, which was restored upon sulfate supply. In contrast, the mutant showed a higher daily increase rate of LR density relative to the wild-type under prolonged S deficiency, which was diminished to the wild-type level upon sulfate supply, suggesting that CLV1 directs a signal to inhibit LR development under S-deficient conditions. and transcript levels decreased under S deficiency and through CLV1-mediated feedback regulations, suggesting the levels of CLE peptide signals are adjusted during the course of LR development. This study demonstrates a fine-tuned mechanism for LR development coordinately regulated by CLE-CLV1 signaling and in response to changes in S availability.
植物根系结构会因土壤环境中大量营养素的可利用性而发生剧烈变化。尽管根系对硫（S）的吸收在植物生长和繁殖中很重要，但响应硫可利用性时根系发育的分子机制尚未完全阐明。我们在此报告由CLAVATA3（CLV3）/胚胎周围区域（CLE）肽和CLAVATA1（CLV1）富含亮氨酸重复序列受体激酶组成的信号模块，其在硫可利用性发生变化时调节侧根（LR）发育。暴露于长期缺硫环境下的野生型幼苗表现出侧根密度低的表型，在供应硫酸盐后恢复正常。相反，在长期缺硫条件下，突变体相对于野生型表现出更高的侧根密度日增长率，在供应硫酸盐后降至野生型水平，这表明CLV1在缺硫条件下传递抑制侧根发育的信号。在缺硫条件下， 和 的转录水平下降，并通过CLV1介导的反馈调节，这表明在侧根发育过程中CLE肽信号水平得到了调整。本研究证明了由CLE-CLV1信号协调调节并响应硫可利用性变化的侧根发育精细调节机制。
