精子细胞有能力分离染色体,尽管中心点重复失败
Marnie W Skinner1,2, Carter J Simington1, Pablo López-Jiménez3,4
1Department of Biochemistry and Molecular Biology, Johns Hopkins University Bloomberg School of Public Health, Baltimore, MD, USA.
EMBO reports
|June 28, 2024
概括
在精子生成过程中,当中心球重复失败时,非中心体微管组织中心 (MTOCs) 会调解染色体分离. 然而,中心蛋白对于后来的精子发育和生育能力至关重要.
科学领域:
- 细胞生物学 细胞生物学
- 生殖生物学 生殖生物学
- 分子生物学分子生物学
背景情况:
- 中心体,由中心体和周心体矩阵 (PCM) 组成,是大多数哺乳动物细胞中的主要微管组织中心 (MTOC).
- 在精子生成过程中,中心细胞复制两次,不同于线粒分裂中的单重复.
- 中心体和替代MTOCs在男性半球变异中的作用尚未完全理解.
研究的目的:
- 调查非中心体MTOCs (ncMTOCs) 在染色体分离中的作用,当在精子生成过程中抑制中心体重复时.
- 为了确定参与ncMTOC形成和功能中的分子因素,在没有中心体的情况下.
- 确定对精子生成和生育能力的后期阶段中枢细胞和PLK4的必要性.
主要方法:
- 利用老鼠突变物和化学抑制来阻止精子生成期间的中心重复.
- 进行了深入的分析,以确定局部化到ncMTOCs的蛋白质.
- 在实验条件下评估染色体分离,精子生成和鞭毛组装.
主要成果:
- 证明ncMTOCs可以有效地调解在精子发生过程中缺少中心球时的染色体分离.
- 鉴定了六种与微管相关的蛋白质 (TPX2,KIF11,NuMA和CAMSAP1-3),它们局部化到ncMTOCs,并促进双极MTOC的形成.
- 证实,尽管化成功,但中心点遗传和PLK4功能对于正常的精子生成和鞭毛组装是不可或缺的.
结论:
- 精子生成可以通过半转化进行,并在中心点重复受损时通过ncMTOCs形成圆形精子.
- 特定的微管相关蛋白质对于男性半导体变异过程中ncMTOCs的组装和功能至关重要.
- 中心细胞和PLK4对于精子的终端分化和随后的生育能力至关重要,突出显示了男性生育过程中的不同角色.
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