Open Access. Powered by Scholars. Published by Universities.®
- Discipline
- Institution
- Publication
- Publication Type
Articles 1 - 7 of 7
Full-Text Articles in Molecular Biology
Two Dot1 Enzymes Cooperatively Mediate Efficient Ubiquitin-Independent Histone H3 Lysine 76 Tri-Methylation In Kinetoplastids, Victoria Frisbie, Hideharu Hashimoto, Yixuan Xie, Francisca De Luna Vitorino, Josue Baeza, Tam Nguyen, Zhangerjiao Yuan, Janna Kiselar, Benjamin Garcia, Erik Debler
Two Dot1 Enzymes Cooperatively Mediate Efficient Ubiquitin-Independent Histone H3 Lysine 76 Tri-Methylation In Kinetoplastids, Victoria Frisbie, Hideharu Hashimoto, Yixuan Xie, Francisca De Luna Vitorino, Josue Baeza, Tam Nguyen, Zhangerjiao Yuan, Janna Kiselar, Benjamin Garcia, Erik Debler
Department of Biochemistry and Molecular Biology Faculty Papers
In higher eukaryotes, a single DOT1 histone H3 lysine 79 (H3K79) methyltransferase processively produces H3K79me2/me3 through histone H2B mono-ubiquitin interaction, while the kinetoplastid Trypanosoma brucei di-methyltransferase DOT1A and tri-methyltransferase DOT1B efficiently methylate the homologous H3K76 without H2B mono-ubiquitination. Based on structural and biochemical analyses of DOT1A, we identify key residues in the methyltransferase motifs VI and X for efficient ubiquitin-independent H3K76 methylation in kinetoplastids. Substitution of a basic to an acidic residue within motif VI (Gx6K) is essential to stabilize the DOT1A enzyme-substrate complex, while substitution of the motif X sequence VYGE by CAKS renders a rigid active-site …
Transcriptomic And Epigenetic Responses To Environmental Stress In Marine Bivalves With A Focus On Harmful Algal Blooms, Maria Victoria Suarez Ulloa
Transcriptomic And Epigenetic Responses To Environmental Stress In Marine Bivalves With A Focus On Harmful Algal Blooms, Maria Victoria Suarez Ulloa
FIU Electronic Theses and Dissertations
Global change poses new threats for life in the oceans forcing marine organisms to respond through molecular acclimatory and adaptive strategies. Although bivalve molluscs are particularly tolerant and resilient to environmental stress, they must now face the challenge of more frequent and severe Harmful Algal Blooms (HABs) episodes. These massive outbreaks of microalgae produce toxins that accumulate in the tissues of these filter-feeder organisms, causing changes in their gene expression profiles, which in turn modify their phenotype in order to maintain homeostasis. Such modifications in gene expression are modulated by epigenetic mechanisms elicited by specific environmental stimuli, laying the foundations …
Characterization Of Histone Mutants Associated With Mitotic Defects In Saccharomyces Cerevisiae, Md Riajul Hossain
Characterization Of Histone Mutants Associated With Mitotic Defects In Saccharomyces Cerevisiae, Md Riajul Hossain
Graduate Theses and Dissertations
Nucleosomes, the basic unit and the building blocks of chromatin have an essential role in the tight packaging of DNA into higher order chromatin. Work from our lab and others have provided information on the contributions of different histone proteins and specific domains within the nucleosome made to create the centromeric chromatin structure required for normal chromosome segregation during mitosis. The DNA entry/exit site is a particular region of the nucleosome where histone H2A, H3 and H4 form critical interactions that appear to be essential for the association of Sgo1, a tension sensing protein that monitors kinetochore-microtubule attachment. In our …
The Role Of Histone H3 And H4 In Centromere Function And Genome Integrity, Payel Chaudhuri
The Role Of Histone H3 And H4 In Centromere Function And Genome Integrity, Payel Chaudhuri
Graduate Theses and Dissertations
Histone H2A plays an important role in chromosomal segregation among parent and daughter cells during mitosis. While it is established that this histone is important in maintaining chromosome number in cell, further work is carried out to explore the role of other histones like H3 and H4 for similar effects. A systematic study is initiated by screening a library based on mutation of different amino acid residues in these histones. This detailed screening identified specific regions within H3 and H4, which are critically important for centromeric function. These histones residing near the DNA entry/exit region of nucleosome effects the functionality …
Gene Expression Studies For The Analysis Of Domoic Acid Production In The Marine Diatom Pseudo-Nitzschia Multiseries, Katie Boissonneault, Brooks M. Henningsen, Stephen S. Bates, Deborah L. Robertson, Sean Milton, Jerry Pelletier, Deborah A. Hogan, David E. Housman
Gene Expression Studies For The Analysis Of Domoic Acid Production In The Marine Diatom Pseudo-Nitzschia Multiseries, Katie Boissonneault, Brooks M. Henningsen, Stephen S. Bates, Deborah L. Robertson, Sean Milton, Jerry Pelletier, Deborah A. Hogan, David E. Housman
Dartmouth Scholarship
Pseudo-nitzschia multiseries Hasle (Hasle) (Ps-n) is distinctive among the ecologically important marine diatoms because it produces the neurotoxin domoic acid. Although the biology of Ps-n has been investigated intensely, the characterization of the genes and biochemical pathways leading to domoic acid biosynthesis has been limited. To identify transcripts whose levels correlate with domoic acid production, we analyzed Ps-n under conditions of high and low domoic acid production by cDNA microarray technology and reverse-transcription quantitative PCR (RT-qPCR) methods. Our goals included identifying and validating robust reference genes for Ps-n RNA expression analysis under these conditions.
Understanding The Role Of Histones During Chromosome Segregation: A Study Of The Effects Of Histone Gene Dosage In Saccharomyces Cerevisiae, Rebecca Leigh Danforth
Understanding The Role Of Histones During Chromosome Segregation: A Study Of The Effects Of Histone Gene Dosage In Saccharomyces Cerevisiae, Rebecca Leigh Danforth
Graduate Theses and Dissertations
Chromatin plays a role in all cellular functions that involve DNA. These include, but are not limited to replication, recombination, transcription, and chromosome segregation. Chromosome segregation is an extremely well conserved cellular process and is essential for maintaining the genetic integrity of a cell. There is very strong evidence indicating that chromatin structure is critical for maintaining the fidelity of chromosome transmission, but its specific role(s) in this process remains unclear. Chromatin is comprised of arrays of nucleosomes that serve to compact DNA. These nucleosomes consist of 146 bp of DNA that is wrapped around a histone octamer; two each …
Isolation And Partial Characterization Of Basic, Sperm-Specific, Nuclear Proteins In The Dog And Hampster, Richard William Hall
Isolation And Partial Characterization Of Basic, Sperm-Specific, Nuclear Proteins In The Dog And Hampster, Richard William Hall
Biological Sciences Theses & Dissertations
The purpose was to determine whether dogs and hamsters contain the same sperm-specific protamine and testis specific proteins (TP) as other eutherian mammals previously studied. The proteins (protamine and TPs) were isolated from spermatids and mature spermatozoa, and were subjected to electrophoresis in an acid-urea, polyacrylamide gel system according to the procedure of Panyim and Chalkley (1962). The results indicated that, regardless of the anatomical location of sperm acquisition, acid precipitation technique, or denaturing agents used, epididymal and testicular samples from both the dog and hamster contained protamine in elongated spermatids and mature spermatozoa. The protamines from dogs and hamsters …