Bowerman, BruceSchlientz, Aleesa2020-09-242020-09-242020-09-24https://hdl.handle.net/1794/25630Meiosis, the specialized cell division process that results in haploid gamete formation, is characterized by a single round of genome duplication followed by two successive divisions. During meiosis, replicated homologous chromosomes must pair and recombine or cross-over to allow for efficient chromosome segregation and formation of daughter cells with the correct chromosomal content. Defects in the meiotic division process, including the failure or mis-segregation of chromosomes or failed cytokinesis, can lead to complications such as aneuploid disorders (ex. trisomy 21), miscarriages, or infertility. Female gamete precursors, called oocytes, are remarkably error-prone during the meiotic division process, with approximately 10-30% of human oocytes having an incorrect number of chromosomes. Interestingly, the process of both spindle assembly and cytokinesis are unique in oocytes and differ greatly from the mitotic and sperm meiotic processes, with oocytes forming spindles in the absence of centrosomes and the cytokinetic apparatus, the polar body contractile ring, forming distal to both spindle poles rather than between them. These aspects of the meiotic division process lead to a number of questions about the requirements for building a meiotic spindle in the absence of centrosomes, segregating chromosomes, assembling a contractile ring, and the potential relationships between these processes. To better understand the oocyte meiotic division process, we used a combination of Caenorhabditis elegans genetics and spinning-disk confocal time-lapse microscopy to live-image the meiotic divisions in oocytes. We examined the requirements for the earliest stages of meiotic spindle assembly, focusing on microtubule nucleation and spindle formation dynamics, the impact of supernumerary crossovers on the process of chromosome segregation, and the relationship between oocyte meiotic spindle assembly/chromosome segregation on the assembly and dynamics of the cytokinetic contractile ring. These analyses allow for a better understanding of the functional requirements of the oocyte meiotic division process This dissertation includes unpublished co-authored material.en-USAll Rights Reserved.Chromosome SegregationMeiosisPolar Body ExtrusionSpindle AssemblyElectronic Thesis or Dissertation