细胞松弛素B对牛卵母细胞体外成熟过程中微管、微丝及染色体的影响  

Effect of Cytochalasin B on Microtubules,Microfilaments and Chromosomes During in vitro Maturation of Bovine Oocytes

作　　者：刘欣[1] 胡晓明[1] 白春玲[1] 程磊[1] 郜宇[1] 刘扬[1] 李光鹏[1] 

机构地区：[1]内蒙古大学生殖生物学及生物技术教育部重点实验室,呼和浩特010021

出　　处：《中国农业科技导报》2011年第6期54-60,共7页Journal of Agricultural Science and Technology

基　　金：国家863计划项目(2008AA10Z159);教育部科技创新团队基金资助

摘　　要：细胞松弛素B(Cytochalasin B,CB)是一种抑制微丝聚合的药物,能抑制微丝的组装从而阻止胞质分裂和极体排放,是研究细胞分裂器形成与变化的重要药物。在牛卵母细胞体外成熟培养过程中加入7.5μg/mL的CB进行处理,分析CB对减数分裂过程中细胞骨架形态、染色体的排列与分离等方面的影响。结果显示,CB处理后卵母细胞第一极体的排放受到了抑制,染色体的排列和分离受到了影响,出现了同源染色体分离不完全或分离不均匀及分离后又聚在一起等异常情况,形成许多二倍体卵母细胞;纺锤体微管的形态发生了变化,出现了两个纺锤体、巨大纺锤体和多极纺锤体等异常结构;微丝的正常分布受到了影响,染色体周围没有或少有微丝分布,皮质下的微丝分布也变得少而不均匀;这说明微丝与微管在减数分裂过程中是协同作用的,CB通过影响微丝的动态变化,改变了纺锤体微管的形态结构,最终抑制了极体的排放。Cytochalasin B （ CB）, a reagent inhibiting actin polymerization, can inhibit the assembly of actin and prevent cytokinesis and polar body （ PB1 ） emission, and it is usually used to study the formation and dynamic changes of meiotic （mitotic） apparatus. In this study, the effect of CB on meiotic spindle configuration, chromosome alignment and separation was investigated after the oocytes were incubated at the presence of 7.5μg/mL CB. The results showed that CB inhibited the emission of PBl and resulted in the formation of abnormal patterns of chromosomal alignment and separation such as the incomplete separation of homologous chromosomes. CB treatment caused meiotic arrest at anaphase I stage and induced the formation of 2 groups of chromosomes, which then moved toward in proximity or merged entirely to yield the formation of diploid oocytes. Meanwhile, CB treatment led to the disfiguration of spindle microtubules and induced 2 spindles, a large spindle, and multiple-poles spindles. CB also affected the microfilament distribution. Almost no or less microfilaments were observed around the chromosomes, and their distribution in the sub-cortical areas was less and uneven. These results suggested that meiosis require synergetic action of microtubules and microfilaments. CB caused the disfigurations of meiotic spindles by interfering the dynamic pattern formation of microtubules and microfilaments, and ultimately inhibited the emission of polar bodies.

关 键 词：牛卵母细胞 细胞松弛素B 减数分裂 微丝 微管 染色体 

分 类 号：Q813[生物学—生物工程] S858.23[农业科学—临床兽医学]