State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Tai'an, Shandong, China.
State Key Laboratory of Crop Biology, College of Agronomy, Shandong Agricultural University, Tai'an, Shandong, China.
Mol Plant Pathol. 2021 Jan;22(1):48-63. doi: 10.1111/mpp.13007. Epub 2020 Oct 29.
Nonspecific lipidtransfer proteins (nsLTPs), which are small, cysteine-rich proteins, belong to the pathogenesis-related protein family, and several of them act as positive regulators during plant disease resistance. However, the underlying molecular mechanisms of these proteins in plant immune responses are unclear. In this study, a typical nsLTP gene, StLTP10, was identified and functionally analysed in potato. StLTP10 expression was significantly induced by Phytophthora infestans, which causes late blight in potato, and defence-related phytohormones, including abscisic acid (ABA), salicylic acid, and jasmonic acid. Characterization of StLTP10-overexpressing and knockdown lines indicated that StLTP10 positively regulates plant resistance to P. infestans. This resistance was coupled with enhanced expression of reactive oxygen species scavenging- and defence-related genes. Furthermore, we identified that StLTP10 physically interacts with ABA receptor PYL4 and affects its subcellular localization. These two proteins work together to regulate stomatal closure during pathogen infection. Interestingly, we also found that wound-induced protein kinase interacts with StLTP10 and positively regulates its protein abundance. Taken together, our results provide insight into the role of StLTP10 in resistance to P. infestans and suggest candidates to enhance broad-spectrum resistance to pathogens in potato.
非特异性脂质转移蛋白（nsLTPs）是一类富含半胱氨酸的小分子蛋白，属于植物病程相关蛋白家族，其中一些蛋白在植物抗病反应中作为正调控因子发挥作用。然而，这些蛋白在植物免疫反应中的潜在分子机制尚不清楚。本研究在马铃薯中鉴定并分析了一个典型的 nsLTP 基因 StLTP10。StLTP10 的表达受致病疫霉诱导显著上调，致病疫霉引起马铃薯晚疫病，防御相关的植物激素如脱落酸（ABA）、水杨酸和茉莉酸也能诱导其表达。过表达和敲低 StLTP10 植株的鉴定表明，StLTP10 正向调控马铃薯对致病疫霉的抗性。这种抗性与活性氧清除和防御相关基因的表达增强有关。此外，我们鉴定到 StLTP10 与 ABA 受体 PYL4 发生物理互作，并影响其亚细胞定位。这两种蛋白共同作用，调控病原菌侵染过程中的气孔关闭。有趣的是，我们还发现，伤口诱导蛋白激酶与 StLTP10 互作，并正向调控其蛋白丰度。综上，本研究结果阐明了 StLTP10 在马铃薯抗致病疫霉过程中的作用，并为提高马铃薯对病原菌的广谱抗性提供了候选基因。
