本论文与2017年11月13日发表于PLOS GENETICS，原文题目如下：The karrikin receptor KAI2 promotes drought resistance in Arabidopsis thaliana

干旱导致作物产量大大降低，我们致力于寻找调控拟南芥抗旱性的化学和遗传因素。Karrikins(KAR)是烟中发现一种可以促进种子萌发的丁烯酸内脂化合物，已报到其在逆境下可以提高种子活力。本文研究发现KARRIKIN INSENSITIVE2(KAI2) 编码了一种KAR受体，其突变体对缺水高度敏感。本文从转录组学，生理学，生物化学等方面具体分析其抗旱性。kai2突变体水分流失加快，干旱诱导的细胞膜受损加重，气孔开度增大，表皮渗透性提高。此外，干旱导致kai2花青素合成减少，气孔开度以及子叶张开对ABA高度敏感。通过转录组分析鉴定出一些与观察到的生理和生化变化相关的基因。数据表明ABA信号途径和KAI2-依赖的信号途径在调控植物抗旱方面存在相关性。此外，本文为KAI2与D14信号在调控植物抗旱方面提供新思路。

Drought causes substantial reductions in crop yields worldwide. Therefore, we set out to identify new chemical and genetic factors that regulate drought resistance in Arabidopsis thaliana. Karrikins (KARs) are a class of butenolide compounds found in smoke that promote seed germination, and have been reported to improve seedling vigor under stressful growth conditions. Here, we discovered that mutations in KARRIKIN INSENSITIVE2 (KAI2), encoding the proposed karrikin receptor, result in hypersensitivity to water deprivation. We performed transcriptomic, physiological and biochemical analyses of kai2 plants to understand the basis for KAI2-regulated drought resistance. We found that kai2 mutants have increased rates of water loss and drought-induced cell membrane damage, enlarged stomatal apertures, and higher cuticular permeability. In addition, kai2 plants have reduced anthocyanin biosynthesis during drought, and are hyposensitive to abscisic acid (ABA) in stomatal closure and cotyledon opening assays. We identified genes that are likely associated with the observed physiological and biochemical changes through a genome-wide transcriptome analysis of kai2 under both well-watered and dehydration conditions. These data provide evidence for crosstalk between ABA- and KAI2-dependent signaling pathways in regulating plant responses to drought. A comparison of the strigolactone-insensitive mutant d14 (DWARF14) to kai2 indicated that strigolactones also contributes to plant drought adaptation, although not by affecting cuticle development. Our findings suggest that chemical or genetic manipulation of KAI2 and D14 signaling may provide novel ways to improve drought resistance.

每日一词：

hyposensitive

英[ˌhaɪpə'sensɪtɪv]

美[ˌhaɪpə'sensɪtɪv]

adj. 弱敏的，敏感度减弱的;

[例句]Determination of magnesium in rare earth-magnesium intermediate alloy by atomic absorption spectrometry with hyposensitive line

次灵敏线火焰原子吸收光谱法测定稀土-镁中间合金中镁