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Full-Text Articles in Life Sciences
Dissecting Mammalian Replication-Independent Chromatin Assembly €“ Biochemical And Structural Studies On The H3.3-Specific Histone Chaperones Hira And Daxx, Simon Elsässer
Student Theses and Dissertations
Histones are architectural proteins that wrap approximately two turns of DNA around their octameric core structure, constituting the fundamental packaging unit of eukaryotic chromatin – the nucleosome. Beyond their structural role, they regulate virtually all processes that act on or depend on DNA, such as replication, gene expression and maintenance of centromeres and telomeres. Despite the high conservation of the four core histones, H3, H4, H2A and H2B, throughout all eukaryotes, histone variants have emerged with variable degree of divergence from their canonical counterparts. These variants are thought to expand the regulatory repertoire of chromatin. The histone replacement variant H3.3 …
Mechanistic Insights Into The Stimulation Of Dot1l-Mediated Methylation Of Histone H3 By Semisynthetically Ubiquitylated Histone H2b, Robert Kendall Mcginty
Mechanistic Insights Into The Stimulation Of Dot1l-Mediated Methylation Of Histone H3 By Semisynthetically Ubiquitylated Histone H2b, Robert Kendall Mcginty
Student Theses and Dissertations
Post-translational modification of histones plays an integral role in regulation of chromatin-templated processes through modulation of chromatin structure and function. One such modification, ubiquitylation of histone H2B on lysine 120 (uH2B), has been correlated with enhanced methylation of lysine 79 (K79) of histone H3 by K79-specific methyltransferase, disruptor of telomeric silencing-like (Dot1L/KMT4). However, the specific function of uH2B in this crosstalk pathway was not understood, in part due to the challenges associated with isolating or generating homogeneously ubiquitylated H2B for use in biochemical studies. As both modifications are integral to transcriptional regulation and DNA damage repair, full elucidation of their …
Genome-Wide Localization And Novel Deposition Pathways Of Histone Variant H3.3 In Embryonic Stem And Neuronal Precursor Cells, Aaron David Goldberg
Genome-Wide Localization And Novel Deposition Pathways Of Histone Variant H3.3 In Embryonic Stem And Neuronal Precursor Cells, Aaron David Goldberg
Student Theses and Dissertations
The eukaryotic genome is composed of chromatin, a complex polymer of genomic DNA, RNA, and closely associated proteins. Histone proteins form the core of the nucleosome, the fundamental repeating unit of chromatin. Variant histone proteins play critical roles in the epigenetic regulation of gene expression and in the development of multicellular organisms. In this thesis, I describe the first genome-wide profiles of histone H3 variants in pluripotent mammalian embryonic stem (ES) cells, and I establish the dependence and independence of these patterns on the histone chaperone Hira. To distinguish H3 variants, I use designed zinc finger nucleases (ZFNs) to rapidly …
Regulated Histone H3 Proteolysis During Mouse Embryonic Stem Cell Differentiation, Elizabeth M. Duncan
Regulated Histone H3 Proteolysis During Mouse Embryonic Stem Cell Differentiation, Elizabeth M. Duncan
Student Theses and Dissertations
The association of genomic DNA with histone proteins in the three-dimensional structure known as chromatin is the central framework for “epigenetics,†which is defined as inherited phenotypes governed by differences that cannot be explained by changes in DNA sequence. In recent years, studies have shown that regulated changes in the chemical and physical properties of chromatin often lead to dynamic changes in many cellular processes, including development and differentiation, by affecting the accessibility of the genomic information stored in the DNA. The cell uses many different mechanisms to regulate chromatin in order to establish, maintain, and propagate patterns of gene …
Regulation Of The Heterochromatin Protein 1 By Phosphorylation Of Histone H3 And The Hp1 Hinge Domain, Holger Dormann
Regulation Of The Heterochromatin Protein 1 By Phosphorylation Of Histone H3 And The Hp1 Hinge Domain, Holger Dormann
Student Theses and Dissertations
Chromatin, a polymer formed from DNA, histones, and associated proteins, is the physiological form of genetic information in all eukaryotic cells. Posttranslational modification of histones, such as acetylation, methylation, and phosphorylation, regulates various DNA-dependent processes, ranging from transcription to replication, DNA repair, and apoptosis. A key mechanism by which histone modifications exert these effects is by recruitment of specific binding partners (effector proteins), that in turn direct downstream functions. Insight into the underlying mechanisms are of great importance for a full understanding of chromatin structure and function. One of these effector proteins, Heterochromatin Protein 1 (HP1), plays important roles in …