橡胶粒子是天然橡胶合成和储存的场所，其膜表面丰度最高的蛋白是小橡胶粒子膜蛋白（SRPP）和橡胶延伸因子（REF）。SRPP和REF属于同一个基因家族，产胶植物中SRPP/REF并不是一个高度保守的家族，其蛋白的序列和成员数量均差异较大。我们推测不同起源的产胶植物基因组内可能都发生了SRPP/REF家族的扩张，其中的关键成员在天然橡胶合成中发挥重要的作用。我们的前期研究还发现橡胶树中该家族蛋白的磷酸化修饰在天然橡胶合成中发挥重要作用。本项目拟对产胶植物的SRPP/REF蛋白家族进行进化、基因及蛋白表达谱、亚细胞定位分析，鉴定产胶植物共有的关键成员，并利用双向电泳和液质联用系统测定其磷酸化修饰，进一步在天然橡胶合成模式植物橡胶草中进行遗传转化验证关键成员的功能及其磷酸化修饰的调控作用。研究结果有助于加深对SRPP/REF家族起源和功能的理解，并为分子遗传育种改良橡胶树提供新的基因靶点。

Rubber particles are the natural rubber biosynthesis and storage organelles. The most abundant proteins on the membrane of rubber particles are small rubber particle protein (SRPP) and rubber elongation factor (REF), which belong to the same gene family. The SRPP/REF family is not highly conserved among rubber-producing plants as the protein sequences and number of family members are different. We assume that SRPP/REF family has expanded among rubber-producing plants of different origins. We also found that phosphorylation of SRPP/REF family proteins played important roles in natural rubber biosynthesis. This research project plans to investigate the evolutionary relations, transcript and protein expression profiles, sub-cellular location of SRPP/REF family among rubber-producing plants to identify key family members common in rubber-producing plants and further determine the phosphorylation profiles of SRPP/REF proteins using LC-MS/MS system. Furthermore, validate the genetic function of the key SRPP/REF members and their phosphorylation sites using transgenic system in rubber grass. The results will be helpful for better understanding of the origins and functions of SRPP/REF family, as well as provide novel target genes for molecular genetic breeding of rubber tree.