正常培养条件下绵羊卵母细胞减数分裂从中期Ⅰ至中期Ⅲ的动态变化过程  

Dynamic Changes of Sheep Oocyte Meiosis from Metaphase Ⅰ to Metaphase Ⅲ Matured in vitro

作　　者：李欣欣[1] 白春玲[1] 魏著英[1] 李光鹏[1] 

机构地区：[1]内蒙古大学哺乳动物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：《生物技术通报》2016年第5期226-233,共8页Biotechnology Bulletin

基　　金：国家重点基础研究发展计划(2012CB722306);内蒙古科技项目(20130902;20110401)

摘　　要：以绵羊卵母细胞为研究对象,通过免疫组织化学的方法研究其染色体和纺锤体微管及微丝在体外成熟、孤雌激活过程中的动态变化。结果表明:(1)纺锤体的形态由中期的桶形,变成早后期的圆柱形及后期和末期细长而扁平的三角锥形,与椎体底面连接的染色质将来进入极体并最终被排出。(2)染色体形态从中期单个的清晰可见的状态,变为后期和末期凝缩的染色质状态,随后在下一个中期再次呈现出清晰可见的形态。(3)第一次减数分裂中期(MI)纺锤体比第二次减数分裂中期(MII)和第三次减数分裂中期(MIII)大,但MII期纺锤体形态比MI期更接近桶形。(4)几乎所有组成纺锤体的微管和微丝都被分配到极体中。Meiosis is a division mode in diploid organism to produce haploid gametes,which is the special mechanism of ensuring the chromosome＇s number of a species after fertilization to be constant. The key step in the meiotic division is to separate the homologous chromosome and sister chromatids correctly,the dynamic changes of the cytoskeleton,in particular microtubules（MTs）and microfilaments（MFs）,play critical roles in this process. In this study,the dynamic changes of chromosomes and spindle MTs and MFs during the maturing and parthenogenetic activation of sheep oocyte cells were studied by immunohistochemistry method. The results showed that ：1）The morphology of spindle changed from barrel-shaped at metaphase stage to cylinder-shaped at early anaphase,and then to long,thin coneshaped at late anaphase and telophase. Chromatin connected with the floor of the cone became the polar bodies and expelled. 2）Chromosome morphology changed from visible individual at metaphase to condensed chromatin during anaphase and telophase stages,and then backed to visible individual chromosomes at the next metaphase. 3）The size of MI spindle was larger than that of the MII spindle and MIII. MII spindle,however,was more barrel-shaped than the MI spindle. 4）Almost all of the MTs and MFs composing the spindles were partitioned into the polar bodies.

关 键 词：减数分裂 微管 微丝 纺锤体 卵母细胞 绵羊 

分 类 号：S826[农业科学—畜牧学]