粘液繁殖体种子的粘液质形成、分泌及释放相关基因

Genes Involved in Biosynthesis,Secretion and Release of Seed Coat Mucilage of Myxospermy

种皮粘液质是在种皮外层细胞的高尔基体内产生并分泌到胞腔内或细胞壁层的一种果胶类多糖物质.当干燥种子遇水后,粘液质即刻被释放形成透明胶质并完全包被整个种子.粘液质对种子的扩散定居、种子萌发以及幼苗的存活和生长均具有重要作用.粘液质作为一种模型研究细胞壁的产生及其形成的分子机制已经成为植物种皮发育与环境变化相适应关系的研究热点.本文主要对以拟南芥为代表的粘液质细胞和调控粘液质形成及释放相关基因的研究进展进行了综述,并对今后的研究方向进行了展望,以期为促进具粘液繁殖体植物的理论与应用研究,以及西部荒漠区的植物物种多样性保护提供科学依据.

eed coat mucilage consists of pectin polysaccharides secreted by the Golgi apparatus in epidermal cells to the cell cavity and cell walls of the seed coat.The striking feature of the myxospermy is formation of a gelatin-like capsule（mucilage） around the seed upon contact with water,which is believed to help with seed hydration,ecologically advantageous for seed dispersal,germination,seedling survival and establishment.The molecular mechanism of mucilage synthesis and its novel system to dissect cell wall production are important to study the relationship between seed coat and complex environment.In the present review,we intend to introduce the latest results achieved in the model plant Arabidopsis thaliana with the mucilage secretory cells（MSCs） differentiation and its regulatory genes in the process of seed coat mucilage biosynthesis,secretion and release.Consequently,the expected direction in this research area is prospected and discussed,we hope to stimulate research in both theory and application of myxospermy plant species,and to provide convincing evidence for protection of biodiversity and utilization of biological resources in the desert region of northwest China.