Ministry of Agriculture Key Laboratory of Biology and Genetic Resources of Rubber Tree, Rubber Research Institute, Chinese Academy of Tropical Agricultural Sciences , Danzhou Hainan 571737, P. R. China.
J Proteome Res. 2013 Nov 1;12(11):5146-59. doi: 10.1021/pr400378c. Epub 2013 Sep 23.
Lutoids are specific vacuole-based organelles within the latex-producing laticifers in rubber tree Hevea brasiliensis. Primary and secondary lutoids are found in the primary and secondary laticifers, respectively. Although both lutoid types perform similar roles in rubber particle aggregation (RPA) and latex coagulation, they vary greatly at the morphological and proteomic levels. To compare the differential proteins and determine the shared proteins of the two lutoid types, a proteomic analysis of lutoid membranes and inclusions was performed, revealing 169 proteins that were functionally classified into 14 families. Biological function analysis revealed that most of the proteins are involved in pathogen defense, chitin catabolism, and proton transport. Comparison of the gene and protein changed patterns and determination of the specific roles of several main lutoid proteins, such as glucanase, hevamine, and hevein, demonstrated that Chitinase and glucanase appeared to play crucial synergistic roles in RPA. Integrative analysis revealed a protein-based metabolic network mediating pH and ion homeostasis, defense response, and RPA in lutoids. From these findings, we developed a modified regulation model for lutoid-mediated RPA that will deepen our understanding of potential mechanisms involved in lutoid-mediated RPA and consequent latex coagulation.
胶乳体是橡胶树 Hevea brasiliensis 产胶乳的乳胶细胞中特有的基于液泡的细胞器。初级和次级胶乳体分别存在于初级和次级乳胶细胞中。尽管两种胶乳体类型在橡胶粒子聚集（RPA）和乳胶凝固中发挥相似的作用，但它们在形态和蛋白质组学水平上有很大的差异。为了比较差异蛋白并确定两种胶乳体类型的共有蛋白，对胶乳体膜和内含物进行了蛋白质组学分析，共鉴定到 169 种蛋白质，它们被功能分类为 14 个家族。生物学功能分析表明，大多数蛋白质参与病原体防御、几丁质分解代谢和质子转运。比较基因和蛋白质变化模式并确定几种主要胶乳体蛋白（如葡聚糖酶、巴西橡胶素和巴西橡胶素）的特定作用表明，几丁质酶和葡聚糖酶似乎在 RPA 中发挥协同作用。综合分析揭示了一个基于蛋白质的代谢网络，介导了液泡中的 pH 和离子稳态、防御反应和 RPA。从这些发现中，我们开发了一个改良的胶乳体介导的 RPA 调控模型，这将加深我们对胶乳体介导的 RPA 及随后的乳胶凝固中潜在机制的理解。
