GSBS Dissertations and Theses
Approval Date
8-10-2016
Document Type
Doctoral Dissertation
Academic Program
Cancer Biology
Department
Molecular, Cell and Cancer Biology Department
First Thesis Advisor
Jennifer Benanti, PhD
Keywords
Cell Cycle, Eukaryotic Cells, Adenosine Triphosphatases, DNA-Binding Proteins, Multiprotein Complexes
Subjects
Dissertations, UMMS; Cell Cycle; Eukaryotic Cells; Adenosine Triphosphatases; DNA-Binding Proteins; Multiprotein Complexes
Abstract
For nearly five decades, the simple eukaryote Saccharomyces cerevisiae has been used as a model for understanding the eukaryotic cell cycle. One vein of this research has focused on understanding how chromosome structure is regulated in relation to the cell cycle. This work characterizes a new mechanism that modulates the chromatin organizing condensin complex, in hopes of furthering the understanding of chromosome structure regulation in eukaryotes.
During mitosis, chromosomes are condensed to facilitate their segregation through a process mediated by the condensin complex. Upon interphase onset, condensation is reversed, allowing for efficient transcription and replication of chromosomes. This work demonstrates that Ycg1, the Cap-G subunit of budding yeast condensin, is cell-cycle regulated with levels peaking in mitosis and decreasing as cells enter G1 phase. The cyclical expression of Ycg1 is unique amongst condensin subunits, and is established by a combination of cell cycle-regulated transcription and constitutive proteasomal degradation. Interestingly, when cyclical expression of Ycg1 is disrupted, condensin formation and chromosome association increases, and cells exhibit a delay in cell-cycle entry. These results demonstrate that Ycg1 levels limit condensin function, and suggest that regulating the expression of an individual condensin subunit helps to coordinate chromosome conformation with the cell cycle. These data, along with recent corroborating results in Drosophila melanogaster suggest that condensin regulation through limiting the expression of a single condensin subunit may be broadly conserved amongst eukaryotes.
Repository Citation
Doughty, TW. Levels of YCG1 Limit Condensin Function during the Cell Cycle: A Dissertation. (2016). University of Massachusetts Medical School. GSBS Dissertations and Theses. Paper 861. DOI: 10.13028/M2ZW2J. https://escholarship.umassmed.edu/gsbs_diss/861
DOI
10.13028/M2ZW2J
DOI Link
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