植物质体Fibrillin蛋白家族的起源、结构和功能

Origin,Structure and Function of Plastid-associated Fibrillin Protein Family in Plants

质体是植物细胞进行光合作用和贮藏有机物的细胞器。Fibrillin是一种由核基因编码的质体脂类结合蛋白,起源于光合原核生物蓝藻,并广泛存在于植物的质体中。其分子大小介于21-42 kDa,pI为4-9。它们含有导肽、脂类结合基序DLDKLQGKWRLLY和细胞粘附基序RGD以及蛋白激酶C结构域。研究表明,该家族基因的表达增强可以维持植物质体的稳定性,调控质体醌（PQ）、三酯酰甘油（TAG）和茉莉酸（JA）的合成,介导脱落酸（ABA）的抗逆信号传导过程。而且该家族基因在植物的生长发育和耐逆性中发挥重要作用。综述了Fibrillin家族成员的蛋白结构特征、基因的表达与功能研究进展,并展望了本领域今后的重点研究方向。

Plastid is an important organelle for photosynthesis and storing organic matter in plant cells. Fibrillins are the nuclear gene-encoding plastid lipid-binding proteins originated from cyanobacteria and are prevalent in plastids of plants. Their molecular weight and pI are 21 - 42 kDa and 4 - 9,respectively. The sequences of fibrillins contain amino-terminal transit peptides,lipid-binding motif DLDKLQGKWRLLY,cellular adhesion motif RGD,and a protein kinase C domain. Previous reports have showed that fibrillins can improve the structural stability of plasmids under adverse environmental stresses,regulate the biosynthesis of plastoquinone（PQ）,triacylglycerol（TAG） and jasmonic acid（JA）,mediate the stress hormone abscisic acid（ ABA） signal transduction pathways in the stress tolerance,and more importantly in plant growth,development and stress tolerance. In this study,fibrillin family genes were reviewed in their protein structure and genetic functions in higher plants. The future key issues and research directions in this field was also been proposed.