Meiosis is a conserved and specialized form of cell division during which a diploid cell generates haploid gametes or spores. This is executed by an initial round of DNA replication followed by two rounds of cell division. During the first round of cell division, meiosis I, homologs each containing two sister chromatids, segregate into each daughter cell. Proper segregation of the homologs is directed by recombination which physically connects the homologs generating the tension required for correct assembly of the spindle. Failure of the homologs to properly segregate results in a nondisjunction event, which can lead to aneuploidy, one of the leading causes of human birth defects. One the most common human birth defects is Down syndrome which is caused by the nondisjunction of chromosome 21 leading to trisomy 21. In this thesis I will describe my investigations into how nuclear architecture directs proper pairing and segregation during meiotic prophase in budding yeast.
The primary function of the nuclear pore is to transport cargo into and out of the nucleus. In addition to transport functions the nuclear pore has also been implicated in directing chromatin architecture and the repair of double strand breaks. Despite the nuclear pore’s multiple roles, its function during meiosis has not been analyzed. In chapter two I described a novel role of the nuclear pore complex protein, Nup2, during meiotic prophase. We found that Nup2 directs chromatin architecture during meiotic prophase to direct proper motion during meiotic prophase.
Analyzing the spore viability of mutant yeast strains is a common assay to determine if a mutation causes meiotic segregation defects. This is because a major contributor to a reduction in spore viability compared to wild-type strains is chromosome nondisjunction. In chapter three I created a theoretical framework of spore inviability using random spore death and meiosis I nondisjunction. Using this model of spore inviability, I created an R-Script to estimate the levels of random spore death and meiosis I nondisjunction using the distributions of live:dead spores from dissected tetrads.
Some files may require a special program or browser plug-in. More Information
|Advisor:||Burgess, Sean M.|
|Commitee:||Britt, Anne, Engebrecht, JoAnne|
|School:||University of California, Davis|
|Department:||Integrative Genetics and Genomics|
|School Location:||United States -- California|
|Source:||DAI-B 77/08(E), Dissertation Abstracts International|
|Keywords:||Homolog pairing, Meiosis, Nondisjunction, Nuclear organization, Nuclear pore complex, Nup2|
Copyright in each Dissertation and Thesis is retained by the author. All Rights Reserved
The supplemental file or files you are about to download were provided to ProQuest by the author as part of a
dissertation or thesis. The supplemental files are provided "AS IS" without warranty. ProQuest is not responsible for the
content, format or impact on the supplemental file(s) on our system. in some cases, the file type may be unknown or
may be a .exe file. We recommend caution as you open such files.
Copyright of the original materials contained in the supplemental file is retained by the author and your access to the
supplemental files is subject to the ProQuest Terms and Conditions of use.
Depending on the size of the file(s) you are downloading, the system may take some time to download them. Please be