Comparative Proteomic Analysis Reveals That Chlorophyll Metabolism Contributes to Leaf Color Changes in Wucai (Brassica campestris L.) Responding to Cold Acclimation
Comparative Proteomic Analysis Reveals That Chlorophyll Metabolism Contributes to Leaf Color Changes in Wucai (Brassica campestris L.) Responding to Cold Acclimation
复制标题
比较蛋白质组学分析揭示叶绿素代谢导致五彩（Brassica Campestris L.）响应冷驯化的叶色变化
DOI：
10.1021/acs.jproteome.9b00016
复制
发表时间：
2019
影响因子：
4.4
通讯作者：
Yuan Lingyun
中科院分区：
文献类型：
--
作者：
Xie Shilei;Nie Libing;Zheng Yushan;Wang Jie;Zhao Mengru;Zhu Shidong;Hou Jinfeng;Chen Guohu;Wang Chenggang;Yuan Lingyun
叶绿素是一种重要的光合色素，在植物生长发育过程中起着关键作用，参与光能捕获和能量转换。本研究以甘蓝型油菜(Brassica campestrisL.)利用外叶绿色、内叶黄色的种质材料(W7-2)，研究了冷驯化对叶片叶绿素代谢的影响。以没有叶色变化的绿叶五彩品种W7-1为对照，研究了W7-2的叶绿素代谢变化。与W7-1相比，W7-2的叶绿素(Chla)和叶绿素b(Chlb)含量在种植后13、21、29、37和45d的5个发育阶段均显著降低。根据两个品种叶片颜色的变化，在21DAP和29DAP进行了基于iTRAQ的定量蛋白质组分析。共鉴定出1409个蛋白质，其中218个蛋白质在两个发育阶段表现出W7-2和W7-1之间的差异积累。差异表达蛋白主要包括叶绿素生物合成、光合作用、碳水化合物代谢、核糖体代谢和翻译后修饰等。在这些DEPS中，NADPH-原叶绿素氧化还原酶(PORB)和镁原卟啉IX螯合酶1(CHLI1)是参与叶绿素(Chl)生物合成的关键酶，与W7-1相比，W7-2在21DAP时表达下调，29DAP时上调。与叶绿素代谢相关的镁螯合酶三个亚基(CHLI1、CHLD和CHLH)、基因组解偶联4(GUN4)和硫氧还蛋白(TRX3)基因在W7-2中的表达也显著下调，其中PORB2显著上调，显著影响了叶绿素的生物合成。此外，W7-2和W7-1在叶绿素代谢方面的差异还表现在光合作用、碳水化合物和能量代谢的变化上。我们发现，W7-2的大多数光合作用蛋白的转录水平显著低于W7-1，与碳水化合物和能量代谢相关的基因表达水平也低于W7-1。因此，本研究结果有助于理解叶片着色响应冷驯化的生理和分子机制。
Chlorophyll is a vital photosynthetic pigment that plays a key role in plant development, participating in light energy capture and energy conversion. In this study, a novel wucai (Brassica campestrisL.) germplasm with green outer leaves and yellow inner leaves at the adult stage (W7–2) was used to examine chlorophyll metabolism response to cold acclimation. A green leaf wucai genotype without leaf color changes named W7–1 was selected as the control to evaluate the chlorophyll metabolism changes of W7–2. Compared to W7–1, the contents of chlorophylla(Chla) and chlorophyllb(Chlb) in W7–2 were significantly reduced at five developmental stages (13, 21, 29, 37, and 45 days after planting (DAP)). An iTRAQ-based quantitative proteomic analysis was carried out at 21 and 29 DAP according to the leaf color changes in both of genotypes. 1409 proteins were identified, while 218 of them displayed differential accumulations between W7–2 and W7–1 during the two developmental stages. The differentially expressed proteins (DEPs) mainly assigned to chlorophyll biosynthesis, photosynthesis, carbohydrate metabolism, ribosome metabolism and posttranslational modification. Among these DEPs, NADPH-protochlorophyllide oxidoreductase (PORB) and Mg-protoporphyrin IX chelatase 1 (CHLI1) were the key enzymes participating in chlorophyll (Chl) biosynthesis, which was down-regulated at 21 DAP and up-regulated at 29 DAP in W7–2 compared with W7–1, respectively. The expression analysis of genes of three subunits of Mg-chelatase (CHLI1,CHLD, andCHLH), Genomes Uncoupled 4 (GUN4), and Thioredoxin (TRX3) associated with chlorophyll metabolism also displayed significant down-regulation in W7–2. In particular,PORBshowed significant up-regulation in W7–2, significantly affecting chlorophyll biosynthesis. Additionally, differences in chlorophyll metabolism between W7–2 and W7–1 were in terms of altered photosynthesis, carbohydrate, and energy metabolism. We found that the transcription levels of most photosynthesis proteins showed significantly lower levels, and the genes expression level, associated with carbohydrate and energy metabolism, were lower in W7–2 than in W7–1. Therefore, the present study results help understand the physiological and molecular mechanisms underlying leaf coloring responding to cold acclimation.