PtrCDPK10 of Poncirus trifoliata functions in dehydration and drought tolerance by reducing ROS accumulation via phosphorylating PtrAPX
PtrCDPK10 of Poncirus trifoliata functions in dehydration and drought tolerance by reducing ROS accumulation via phosphorylating PtrAPX
复制标题
枳实的 PtrCDPK10 通过磷酸化 PtrAPX 减少 ROS 积累，从而发挥脱水和耐旱作用
DOI：
10.1016/j.plantsci.2019.110320
复制
发表时间：
2020-02-01
期刊：
影响因子：
5.2
通讯作者：
Liu, Ji-Hong
中科院分区：
文献类型：
--
作者：
Meng, Lin;Zhang, Qinghua;Liu, Ji-Hong
钙依赖性蛋白激酶（CDPKs）是重要的钙信号转导元件，在调节植物非生物胁迫反应中起着重要作用。然而，大多数CDPKs的生理和调节作用仍然知之甚少。本文报道了枳橙子（Poncirus trifoliate（L.）Raf.）脱水和干旱胁迫耐受性。PtrCDPK10属于CDPK家族的III型亚组，定位于细胞核和质膜。PtrCDPK10的转录水平上调脱水，盐和阿坝处理。过表达PtrCDPK10的转基因枳橙子植株表现出比野生型（WT）增强的脱水耐受性，而VIGS（病毒诱导的基因沉默）介导的PtrCDPK10敲低导致对脱水和干旱胁迫的敏感性升高。酵母双杂交筛选确定了几种蛋白质与PtrCDPK10相互作用，包括抗坏血酸过氧化物酶（PtrAPX）。基于体外激酶测定，PtrCDPK10显示磷酸化PtrAPX。与WT相比，PtrCDPK 10过表达转基因系表现出更高的PtrAPX mRNA丰度和APX活性，并且积累的活性氧显着减少，而PtrCDPK 10沉默的VIGS系表现出PtrAPX表达减少和活性氧水平增加。综上所述，这些结果表明，PtrCDPK10促进脱水和耐旱性，至少部分，磷酸化APX调节活性氧稳态。
Calcium-dependent protein kinases (CDPKs) are important calcium signaling components that have been shown to play crucial roles in modulating plant abiotic stress responses. However, the physiological and regulatory roles of most CDPKs are still poorly understood. Here, we report the functional characterization of PtrCDPK10 from trifoliate orange (Poncirus trifoliate (L.) Raf.) in dehydration and drought stress tolerance. PtrCDPK10, categorized in the Type III subgroup of the CDPK family, was localized to the nucleus and plasma membrane. Transcript levels of PtrCDPK10 were up-regulated by dehydration, salt and ABA treatments. Transgenic trifoliate orange plants overexpressing PtrCDPK10 showed enhanced dehydration tolerance compared with the wild type (WT), whereas VIGS (virus-induced gene silencing)-mediated knockdown of PtrCDPK10 resulted in elevated susceptibility to dehydration and drought stresses. Yeast two-hybrid screening identified several proteins that interacted with PtrCDPK10, including an ascorbate peroxidase (PtrAPX). PtrCDPK10 was shown to phosphorylate PtrAPX based on an in vitro kinase assay. PtrCDPK10-overexpressing transgenic lines exhibited higher PtrAPX mRNA abundance and APX activity and accumulated dramatically less ROS in comparison with the WT, while PtrCDPK10-silenced VIGS lines showed decreased PtrAPX expression and increased ROS level. Taken together, these results demonstrate that PtrCDPK10 promotes dehydration and drought tolerance by, at least in part, phosphorylating APX to modulate ROS homeostasis.