The accurate segregation of chromosomes during female meiosis relies on the precise assembly and function of the meiotic spindle, a dynamic structure primarily composed of microtubules. Despite the crucial role of microtubule dynamics in this process, the relationship between microtubule length and spindle size remains elusive. Leveraging Caenorhabditis elegans as a model system, we combined electron tomography and live imaging to investigate this correlation. Our analysis revealed significant changes in spindle length throughout meiosis, coupled with alterations in microtubule length. Surprisingly, while spindle size decreases during the initial stages of anaphase, the size of antiparallel microtubule overlap decreased as well. Detailed electron tomography shows a positive correlation between microtubule length and spindle size, indicating a role of microtubule length in determining spindle dimensions. Notably, microtubule numbers displayed no significant association with spindle length, highlighting the dominance of microtubule length regulation in spindle size determination. Depletion of the microtubule depolymerase KLP‐7 led to elongated metaphase spindles with increased microtubule length, supporting the link between microtubule length and spindle size. These findings underscore the pivotal role of regulating microtubule dynamics, and thus microtubule length, in governing spindle rearrangements during meiotic division, shedding light on fundamental mechanisms dictating spindle architecture.

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线虫减数分裂中微管长度与纺锤体长度相关

雌性减数分裂过程中染色体的精确分离依赖于减数分裂纺锤体的精确组装和功能，减数分裂纺锤体是一种主要由微管组成的动态结构。尽管微管动力学在此过程中发挥着至关重要的作用，但微管长度和纺锤体尺寸之间的关系仍然难以捉摸。杠杆作用秀丽隐杆线虫作为模型系统，我们结合电子断层扫描和实时成像来研究这种相关性。我们的分析揭示了减数分裂过程中纺锤体长度的显着变化，以及微管长度的变化。令人惊讶的是，虽然纺锤体尺寸在后期的初始阶段减小，但反平行微管重叠的尺寸也减小。详细的电子断层扫描显示微管长度和纺锤体尺寸之间呈正相关，表明微管长度在确定纺锤体尺寸中的作用。值得注意的是，微管数量与纺锤体长度没有显着相关性，突出了微管长度调节在纺锤体尺寸测定中的主导地位。微管解聚酶 KLP-7 的消耗导致中期纺锤体伸长，微管长度增加，支持微管长度和纺锤体尺寸之间的联系。这些发现强调了调节微管动力学以及微管长度在减数分裂期间控制纺锤体重排中的关键作用，揭示了决定纺锤体结构的基本机制。