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Molecular Biology Commons

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Publicly Accessible Penn Dissertations

2016

Epigenetics

Cell Biology

Articles 1 - 3 of 3

Full-Text Articles in Molecular Biology

The Mitotic Genome: Accessibility And Transcriptional Control, Chris Hsiung Jan 2016

The Mitotic Genome: Accessibility And Transcriptional Control, Chris Hsiung

Publicly Accessible Penn Dissertations

Mitosis entails dramatic global alterations to genome structure and regulation, including

chromosome condensation, dissociation of the transcriptional machinery from chromosomes, and transcriptional silencing. Here I report studies that address the macromolecular accessibility of the mitotic genome and the control of transcriptional reactivation upon mitotic exit in a mammalian cell line. The results obtained from measuring the sensitivity of chromatin to DNase I cleavage by sequencing (DNase-seq) in pure mitotic cell populations demonstrate that macromolecular accessibility of the mitotic genome is widely preserved. Thus, steric hindrance from chromatin condensation is insufficient for explaining the eviction of transcription factors from mitotic chromatin ...


Interplay Between P53 And Epigenetic Pathways In Cancer, Jiajun Zhu Jan 2016

Interplay Between P53 And Epigenetic Pathways In Cancer, Jiajun Zhu

Publicly Accessible Penn Dissertations

The human TP53 gene encodes the most potent tumor suppressor protein p53. More than half of all human cancers contain mutations in the TP53 gene, while the majority of the remaining cases involve other mechanisms to inactivate wild-type p53 function. In the first part of my dissertation research, I have explored the mechanism of suppressed wild-type p53 activity in teratocarcinoma. In the teratocarcinoma cell line NTera2, we show that wild-type p53 is mono-methylated at Lysine 370 and Lysine 382. These post-translational modifications contribute to the compromised tumor suppressive activity of p53 despite a high level of wild-type protein in NTera2 ...


Epigenetic Regulation Of The Dlk1-Meg3 Imprinted Locus In Human Islets, Vasumathi Kameswaran Jan 2016

Epigenetic Regulation Of The Dlk1-Meg3 Imprinted Locus In Human Islets, Vasumathi Kameswaran

Publicly Accessible Penn Dissertations

Type 2 diabetes mellitus (T2DM) is a complex metabolic disease characterized by inadequate insulin secretion by the pancreatic β-cell in response to increased blood glucose levels. Despite compelling evidence that T2DM has a high rate of familial aggregation, known genetic risk variants account for less than 10% of the observed heritability. Consequently, post-transcriptional regulators of gene expression, including microRNAs and other noncoding RNAs, have been implicated in the etiology of T2DM, in part due to their ability to simultaneously regulate the expression of hundreds of targets.

To determine if microRNAs are involved in the pathogenesis of human T2DM, I sequenced ...