Key message

The proteomic analysis of vascular tissues in rubber tree reveals differentially expressed proteins related to laticifer differentiation in mature phloem and secondary cell wall formation in mature xylem for latex/wood-yield improvement.

Abstract

Rubber tree (Hevea brasiliensis) is a latex-producing plant that has worldwide economic importance for the rubber and wood industries. Natural rubber latex is produced from laticiferous vessels (laticifers) located in the secondary phloem tissue of rubber trees. Improving latex production from rubber tree clones by studying the molecular genetics of vascular development has received much attention, but less information has been obtained from proteomic approaches. This study performed a comparative proteomic analysis of the vascular tissues in high latex-yield and high wood-yield rubber tree clones. One primary vascular tissue (newly developed stem) and two secondary vascular tissues (mature phloem/laticifers and mature xylem/wood) were investigated by qualitative/quantitative proteomic analysis using GeLC-MS/MS. The differentially expressed proteins (DEPs) in the specific vascular tissues were analyzed, and the protein functions in the biological processes related to vascular development and to the specific characteristics of each clone were clarified. The predicted protein–protein interaction network and GO annotation revealed DEPs related to photosynthesis, carbohydrate metabolism, energy production and jasmonic acid-responsive proteins involved in positive regulation of laticifer differentiation in mature phloem of the high latex-yield clone, while DEPs related to cell cytoskeleton maintenance, secondary cell wall components and auxin-, brassinosteroid-, abscisic acid-responsive proteins involved in xylem differentiation were abundant in mature xylem of the high wood-yield clone. This is the first report to demonstrate the correlation and functions of DEPs in phloem/laticifers and xylem/wood differentiation in rubber trees. The regulation of vascular development could be useful in improvement of latex and wood yields from rubber trees.

中文翻译：

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橡胶树韧皮部和木质部发育相关差异表达蛋白的比较蛋白质组学分析。

关键信息

橡胶树中血管组织的蛋白质组学分析显示，与成熟韧皮部的乳胶质分化和成熟木质部的次生细胞壁形成有关的差异表达蛋白可提高乳胶/木材产量。

抽象

橡胶树（巴西橡胶树）是一家生产乳胶的工厂，对橡胶和木材工业具有全球性的经济意义。天然橡胶胶乳是由位于橡胶树次生韧皮部组织中的生胶容器（laticifers）生产的。通过研究血管发育的分子遗传学来改善橡胶树无性系的乳胶生产倍受关注，但从蛋白质组学方法获得的信息较少。这项研究对高胶乳产量和高木产量橡胶树无性系中的维管组织进行了比较蛋白质组学分析。通过使用GeLC-MS / MS进行定性/定量蛋白质组学分析，研究了一个初级血管组织（新近发育的茎）和两个次级血管组织（成熟韧皮部/韧皮部和成熟木质部/木材）。分析了特定血管组织中的差异表达蛋白（DEP），并阐明了在与血管发育和每个克隆的特定特征有关的生物过程中的蛋白功能。预测的蛋白质-蛋白质相互作用网络和GO注释揭示了与光合作用，碳水化合物代谢，能量产生和茉莉酸反应蛋白有关的DEP，这些蛋白参与了高乳胶产量克隆成熟韧皮部的乳胶分化的正调控，而DEP与细胞有关木质部分化所涉及的细胞骨架维持，次生细胞壁成分和生长素，油菜素甾体，脱落酸响应蛋白在高木材产量克隆的成熟木质部中丰富。这是第一份证明DEPs在韧皮部/生枝胶中和橡胶树木质部/木材分化中的相关性和功能的报告。调节血管发育可能有助于提高橡胶树的胶乳和木材产量。