摘要
莼案（BraseniaschreberiGmel）的绒毡层属腺质绒毡层。四分体时期是绒毡层细胞发育的高峰期，大量膨胀的内质网互相连接，在切面上呈网格结构布满细胞，用三维空间结构分析，内质网形成数量众多的小室，每个小室中充满核糖体。四分体发育后期，内质网小室中的核糖体开始解体，形成高电子密度的球形体，内质网消失后，众多球形体游离于细胞基质中。花粉单核期，球形体通过质膜进入花粉囊。在花粉外壁形成过程中，球形体不断沉积于花粉外壁的胶隙中。核糖体由蛋白质和RNA组成，核糖体形成的高电子密度球形体中的蛋白质沉积于花粉外壁腔隙成为花粉外壁蛋白。
The tepetum of Brasenia schreberi belongs to secretory type, the tapetal cells attain their peak development during tetrad stage. A large amount of enlarged ER connects with each other and shows a reticular structure filling the whole tapetal cell at its sectional view. Basing upon the study and analysis of three－dimensional structure of ER,a great amount of small chambers each fills with ribosomes can be observed. At the late development of tetrad stage,the ribosomes begin to dissociate and high e1ectronic dense globules are formed. The disappearance of ER causes all the globules dispersing into the cell inclusion at monokaryonic stage of pollen development,the globules pass through the plasma membrane and distribute in the pollen sac. They deposit to the cavities of pollen exine continuously during pollen wall formation. Ribosomes are constituted with protein and RNA,the protein portion of high electronic dense globules accumulates to the exine of pollen grains forming the exine protein.
出处
《西北植物学报》
CAS
CSCD
1999年第4期683-687,共5页
Acta Botanica Boreali-Occidentalia Sinica
基金
国家自然科学基金
关键词
莼菜
绒毡层
核糖体
花粉外壁蛋白
Brasenias chreberi Gmel
tapetum
ribosome
exine protein of pollen grain
