寇氏隐甲藻(Crypthecodinium cohnii)中的着丝粒蛋白及有关进化问题分析

用免疫电镜、免疫印迹 (Westernblot)和间接免疫荧光 (IIF)技术研究了原始真核生物寇氏隐甲藻 (Crypthecodiniumcohnii)的着丝粒蛋白 (centromereproteins ,Cenps)。结果显示 :(1)寇氏隐甲藻Cenps相对集中分布于细胞核中及核膜上 ,胞质中分布稀少 (P<0 .0 1) ;(2 )染色体区域Cenps的分布比核内其他区域更加丰富 (P <0 .0 1) ;(3)寇氏隐甲藻具有与高等真核生物相似的和不同的Cenps ,其中有真核生物的主要着丝粒结构蛋白CenpB的同源分子 ;(4 )CenpB在寇氏隐甲藻细胞中具有动态的分布变化。这说明 ,CenpB等Cenps可能在真核生物细胞中具有重要功能 ,在形成着丝粒/动粒 (kinetochore)的演化中发挥一定作用。

Centromere Proteins in Dinoflagellate Crypthecodinium cohniiand an Analysis on the Relavent Evolutionary Problems

Centromere proteins (Cenps) of dinoflagellate Crypthecodinium cohnii were analyzed with immuno-electron-microscopy, Western blot and indirect immuno-fluorescence techniques. The results revealed that (1) Cenps of C. cohnii represent a rather concentrated distribution in the nucleus and on the nuclear membrane, and in the cytoplasm, they express more sparsely (P<0.01); (2)the distribution in chromosome fields is even denser than that in the other areas of the nuclear space (P<0.01); (3) in C. cohnii there are both similar Cenps and different ones of that in high grade eukaryota, and especially, there has been a homolog of CenpB, a main constitutive Cenp of eukaryotes;(4)in C. Cohnii cells, CenpB shows dynamic distribution changes. It is suggested that Cenps such as CenpB probably may have important functions in eucaryotic cells and play a certain role in the formation of the typical centromeres / kinetochores during the evolution.