The change of gravity vector induces short-term phosphoproteomic alterations in Arabidopsis
The change of gravity vector induces short-term phosphoproteomic alterations in Arabidopsis
复制标题
重力矢量的变化引起拟南芥的短期磷酸化蛋白质组变化
DOI：
10.1016/j.jprot.2020.103720
复制
发表时间：
2020-04-30
影响因子：
3.3
通讯作者：
Li，Ning
中科院分区：
文献类型：
--
作者：
Yang，Zhu;Guo，Guangyu;Li，Ning
植物可以感觉到引力。当植物察觉到这一自然力的变化时，它们倾向于相对于重力矢量的方向重新定位它们的器官，即茎干曲线向上。在本研究中，我们应用4C定量磷蛋白质组学方法来鉴定由150 S在地球上的拟南芥植物重新定位引起的蛋白磷酸酶位点的改变。从重力刺激的拟南芥中共鉴定出5556个磷酸肽。基于拟南芥(SIIA)15N稳定同位素标记的定量和对磷酸肽提取二色谱图(XIC)的计算分析表明，分别有8个和5个独特的PTM肽阵列(UPA)在重力刺激下上调和下调。在13个植物重定位反应蛋白质组中，许多与细胞骨架动态和质体运动有关。有趣的是，对重力刺激反应最敏感的磷酸酶是蓝光受体促黄体素1(PHOT1)的三个丝氨酸残基，S350，S376和S410。免疫印迹实验证实重力载体的改变确实影响了PHOT1中S410的磷酸化水平。在丧失功能的双变异体PHOT1和其互补的转基因植物PHOT1/PH1Pho2的黑暗中，重力测量进一步证实了PHOT1在向重力反应中的功能作用。意义固着生物的器官，即植物，能够对环境刺激，如重力载体、触摸、光、水或营养物质做出反应，这被称为向向性。例如，植物新梢对光源的弯曲被称为向光性。由于地球上生长的所有植物都不断地暴露在重力场中，植物接收到重力矢量变化引发的机械信号，并将其转化为植物的形态发生、生长和发育。过去的研究已经得出了不同的重力感应假说，但我们对重力信号如何在植物细胞中传递的了解仍然很少。在本研究中，我们以Asilia为基础，对150-S重力刺激的拟南芥幼苗进行了4C定量磷酸蛋白质组学研究，以探索参与向重力反应的磷酸蛋白。我们的数据表明，拟南芥的这种短期重新定位导致了细胞骨架结构蛋白的磷酸化变化，如叶绿体异常位置1(CHUP1)、Patellin3(PATL3)和质体运动障碍2(PMI2)，以及蓝光受体Phototroin1(PHOT1)。这些结果表明，蛋白质的磷酸化在重力信号中起着至关重要的作用，植物的两种主要的向力反应，向重力性和向光性，可能具有共同的成分和信号转导途径。我们期待本研究检测到的磷化蛋白将有助于后续的分子和细胞研究植物向重力性反应中的信号转导机制。
Plants can sense the gravitational force. When plants perceive a change in this natural force, they tend to reorient their organs with respect to the direction of the gravity vector,i.e., the shoot stem curves up. In the present study, we performed a 4C quantitative phosphoproteomics to identify those altered protein phosphosites resulting from 150 s of reorientation of Arabidopsis plants on earth. A total of 5556 phosphopeptides were identified from the gravistimulated Arabidopsis. Quantification based on the15N-stableisotopelabelinginArabidopsis (SILIA) and computational analysis of the extractedionchromatogram (XIC) of phosphopeptides showed eight and fiveuniquePTM peptidearrays (UPAs) being up- and down-regulated, respectively, by gravistimulation. Among the 13 plant reorientation-responsive protein groups, many are related to the cytoskeleton dynamic and plastid movement. Interestingly, the most gravistimulation-responsive phosphosites are three serine residues, S350, S376, and S410, of a blue light receptor Phototropin 1 (PHOT1). The immunoblots experiment confirmed that the change of gravity vector indeed affected the phosphorylation level of S410 in PHOT1. The functional role of PHOT1 in gravitropic response was further validated with gravicurvature measurement in the darkness of both the loss-of-function double mutantphot1phot2and its complementary transgenic plantPHOT1/phot1phot2.SignificanceThe organs of sessile organisms, plants, are able to move in response to environmental stimuli, such as gravity vector, touch, light, water, or nutrients, which is termed tropism. For instance, the bending of plant shoots to the light source is called phototropism. Since all plants growing on earth are continuously exposed to the gravitational field, plants receive the mechanical signal elicited by the gravity vector change and convert it into plant morphogenesis, growth, and development. Past studies have resulted in various hypotheses for gravisensing, but our knowledge about how the signal of gravity force is transduced in plant cells is still minimal.In the present study, we performed aSILIA-based 4C quantitative phosphoproteomics on 150-s gravistimulated Arabidopsis seedlings to explore the phosphoproteins involved in the gravitropic response. Our data demonstrated that such a short-term reorientation of Arabidopsis caused changes in phosphorylation of cytoskeleton structural proteins like Chloroplast Unusual Positioning1 (CHUP1), Patellin3 (PATL3), and Plastid Movement Impaired2 (PMI2), as well as the blue light receptor Phototropin1 (PHOT1). These results suggested that protein phosphorylation plays a crucial role in gravisignaling, and two primary tropic responses of plants, gravitropism and phototropism, may share some common components and signaling pathways.We expect that the phosphoproteins detected from this study will facilitate the subsequent molecular and cellular studies on the mechanism underlying the signal transduction in plant gravitropic response.