Depletion of pericentrin in mouse oocytes disrupts microtubule organizing center function and meiotic spindle organization.
Depletion of pericentrin in mouse oocytes disrupts microtubule organizing center function and meiotic spindle organization.
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DOI：
10.1002/mrd.22422
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发表时间：
2014-11
影响因子：
2.5
通讯作者：
Viveiros, Maria M.
中科院分区：
文献类型：
--
作者：
Ma, Wei;Viveiros, Maria M.
准确的染色体分离依赖于微管纺锤体的形成和稳定性。卵母细胞的减数分裂纺锤体组装过程不同于有丝分裂过程，由缺乏中心粒的独特微管组织中心（MTOCs）调节。为了深入了解小鼠卵母细胞中无中心mtoc的分子组成和功能，我们评估了一个关键的mtoc相关蛋白——中心周蛋白（PCNT）的作用。在体细胞中，周心蛋白作为一种支架，结合mtoc上的特定蛋白质，包括微管成核所必需的γ-微管蛋白。卵周心蛋白在卵母细胞中表达，但其功能的保存尚不清楚。在从排卵前卵泡中恢复的小鼠卵母细胞中，在前期i期阻滞期间，心周蛋白特异性定位于MTOCs，并且在中期i和中期ii期间仍与纺锤体极点的MTOCs相关。为了测试功能，使用特定的sirna敲除小鼠卵母细胞中的pct转录本。Western blot和免疫荧光分析证实了高效的蛋白消耗。值得注意的是，在pcnt缺失的卵母细胞中，减数分裂纺锤体结构和染色体排列被破坏。大多数卵母细胞（约70%）纺锤体结构紊乱，微管密度降低，染色体排列不一致。此外，在pcnt缺失的卵母细胞中，γ-微管蛋白在MTOCs中的定位显著降低，冷处理后微管再生延迟。因此，心周蛋白是小鼠卵母细胞独特的无中心MTOCs的关键功能成分，并在调节减数分裂纺锤体组装和/或稳定性方面发挥重要作用。
Accurate chromosome segregation is dependent on the formation and stability of the microtubule spindle apparatus. Meiotic spindle assembly in oocytes differs from the process used during mitosis, and is regulated by unique microtubule organizing centers (MTOCs) that lack centrioles. To gain insight into the molecular composition and function of acentriolar MTOCs in mouse oocytes, we assessed the role of a key MTOC-associated protein, pericentrin (PCNT). In somatic cells, pericentrin functions as a scaffold that binds specific proteins at MTOCs, including γ-tubulin, which is necessary for microtubule nucleation. Pericentrin is expressed in oocytes, but the conservation of its function is not known. Pericentrin localizes specifically to MTOCs during prophase-I arrest in mouse oocytes recovered from pre-ovulatory ovarian follicles, and remains associated with MTOCs at spindle poles during metaphase-I and -II. To test function, specific siRNAs were used to knockdown Pcnt transcripts in mouse oocytes. Efficient protein depletion was confirmed by Western blot as well as immunofluorescence analysis. Notably, meiotic spindle structure and chromosome alignment were disrupted in Pcnt-depleted oocytes. Disorganized spindle structures with reduced microtubule density and misaligned chromosomes were observed in the majority of these oocytes (~70%). In addition, γ-tubulin localization to MTOCs was significantly reduced and microtubule regrowth, following cold treatment, was delayed in Pcnt-depleted oocytes. Thus, pericentrin is a key functional component of the unique acentriolar MTOCs of mouse oocytes, and plays an important role in regulating meiotic spindle assembly and/or stability.
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影响因子：
21.3
作者：
Lawo, Steffen;Hasegan, Monica;Pelletier, Laurence
通讯作者：
Pelletier, Laurence
影响因子：
4
作者：
Hinkle, B;Slepchenko, B;Terasaki, M
通讯作者：
Terasaki, M
影响因子：
2.7
作者：
Luksza, Malgorzata;Queguigner, Isabelle;Brunet, Stephane
通讯作者：
Brunet, Stephane
影响因子：
2.7
作者：
Combelles, CMH;Albertini, DF
通讯作者：
Albertini, DF
DOI：
10.1083/jcb.201106093
发表时间：
2011-12-26
期刊：
The Journal of cell biology
影响因子：
--
作者：
Lee K;Rhee K
通讯作者：
Rhee K