Mechanism of cell division in eukaryotes.

真核生物细胞分裂的机制。

基本信息

批准号：
61304008
负责人：
YONEDA Mitsuki
金额：
$ 7.3万
依托单位：
Kyoto University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Co-operative Research (A)
财政年份：
1986
资助国家：
日本
起止时间：
1986 至 1988
项目状态：
已结题

项目摘要

1. Maturation of oocytes and initiation of development (1) Ca activates unfertilized mouse eggs to completion of meiosis. (2) Maturation promoting factor (MPF) may not be a protein activated by phosphorylation. A mRNA, inducing maturation of starfish oocytes, was isolated, which shares homologous sequence with cyclin. (3) Germinal vesicle free frog oocytes still produce MPF, concomitantly with SCW and high cortical stiffness. (4) Ca-wave as seen in activated frog eggs was still detected in normally fertilized eggs. (5) Centrosomal movement toward the formation of mitotic spindle was confirmed in activated starfish oocytes. (6) Role of female nuclei triggering the cell cycle was suggested.2. Chromosomal movement and mitotic spindles (1) Indispensable role of STP in chromosome movement was congirmed in vivo by microinjection experiments. (2) The motive force of chromosomal movement is localized to a region of the spindle close to the chromosomes. The spindle is hardly deformable. (3) Based on observations of half spindies the centrosomes are nor important for the chromosome movement.3. Cytokinesis (1) Amino acid sequences of Tetrahymena actin are 75 % homologous with those in known actins. The actin differs from known actins in its biochemical nature, though with biological function similar to them. (2) Cortex of amphibian eggs acquires the ability to from the contractile ring when the phragmoplast reaches that cortex. (3) Several kinds of actin-regulating proteins at the contractile ring were characterized. Contractile rings rataining the contractility in vitro could be isolated from frog eggs. (4) Fluctuation of Ca-ions accompanying cell cycle was observed in several embryonic cells.

1。卵母细胞的成熟和发育的启动（1）CA激活未施加的小鼠卵以完成减数分裂。（2）促进因子（MPF）可能不是磷酸化激活的蛋白质。分离出诱导海星卵母细胞成熟的mRNA，该mRNA与细胞周期蛋白共有同源序列。（3）无原囊泡无青蛙卵母细胞仍会产生MPF，并与SCW和高皮质刚度同时产生。（4）在正常受精卵中仍检测到激活的青蛙卵中所见的Ca波。（5）在活化的海星卵母细胞中证实了向有丝分裂纺锤体形成的中心体运动。（6）提出了触发细胞周期的雌性核的作用。2。染色体运动和有丝分裂的纺锤体（1）通过微注射实验在体内连接STP在染色体运动中必不可少的作用。（2）染色体运动的动力位于接近染色体的纺锤体区域。主轴几乎是不可变形的。（3）基于对半纺丝的观察，中心体对染色体运动也不重要。3。四膜肌动蛋白的细胞因子（1）氨基酸序列与已知肌动蛋白中的氨基酸序列是75％。肌动蛋白与已知肌动蛋白的生化性质不同，尽管生物学功能与它们相似。（2）两栖鸡蛋的皮层在流向术时从收缩环中获得了从收缩环的能力。（3）在收缩环处表征了几种类型的肌动蛋白调节蛋白。收缩的环可以从青蛙卵中隔离到体外。（4）在几个胚胎细胞中观察到伴随细胞周期的Ca-ions的波动。