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Biochemistry

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Articles 1 - 18 of 18

Full-Text Articles in Molecular Biology

Instability And Extrachromosomal Circular Dna Formation At Microsatellites And Unstable Dna Sequences, Matilyn M. Shanahan Jan 2022

Instability And Extrachromosomal Circular Dna Formation At Microsatellites And Unstable Dna Sequences, Matilyn M. Shanahan

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We have previously documented our evidence of genetic instabilities at the (Pu/Py)78 and (ATTCT)47 sequences and our reasoning for identifying break-induced replication (BIR) as the mode of repair responsible for the mutations in the DNA flanking the unstable inserts. Now, as our lab investigates the protein mechanisms at play in the BIR pathway taking place at these sites, we are also expanding our knowledge of how this mechanism extends into the pathways responsible for forming extrachromosomal circular DNA (eccDNA) molecules. We have documented the phenomena posed as the driving factors for eccDNA formation in our systems containing (Pu/Py)78 and (ATTCT)47. …


Genomic Instability At A Polypurine/Polypyrimidine Repeat Sequence, Nathen S. Zavada Jan 2022

Genomic Instability At A Polypurine/Polypyrimidine Repeat Sequence, Nathen S. Zavada

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Microsatellite repeat sequences have been shown to induce replication stalling, fork collapse, double-strand breaks (DSBs), and possibly stimulate break-induced replication. In this study we use a dual-fluorescent HeLa model that is designed to monitor recombination at an ectopic site through use of flow cytometry and inverse PCR with a microsatellite in the lagging strand for DNA synthesis. To test the stability of the 78 bp polypurine/pyrimidine repeat from the PDK1 locus, we subjected cells to replication stress drugs designed to induce DSBs and measure break-induced replication (BIR). The study revealed that polypurine repeat cells undergo endogenous stress contributing to instability …


Microsatellites And Their Association With Break Induced Replication, French J. Damewood Iv Jan 2021

Microsatellites And Their Association With Break Induced Replication, French J. Damewood Iv

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To study microsatellites instability and their repair pathways a dual fluorescent (DF2) and selectable (ganciclovir sensitive/ thymidine kinase (TK) expressing) cell system was assayed using replication fork stalling agents hydroxyurea and telomestatin. These cell lines carried ectopically integrated microsatellites derived from the Dystrophia Myotonica Protein Kinase (DMPK) gene ((CTG)102 microsatellite), or an 88 bp polypurine/ polypyrimidine (Pu/Py) repeat from the PKD-1 locus, inserted into a FLP recombinase target site. These microsatellites form non-B DNA structures in -vivo and in-vitro causing replication fork stalling and double strand breaks. DF2 myc (CTG)102 -TK cells treated with hydroxyurea were assayed for mutagenesis of …


Enzymatic Post-Translational Halogenation For Adding Functionality To Biomaterials, Alexander L. Compean Jan 2021

Enzymatic Post-Translational Halogenation For Adding Functionality To Biomaterials, Alexander L. Compean

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Silk fibroin from the silkworm, Bombyx mori, is a unique biomaterial that has been extensively studied for a variety of applications due to its promising properties such as controllable self-assembly, robust mechanical properties, and biological compatibility. Previously, there have been numerous methods describing the chemical modification of silk fibroin that utilize synthetic or enzymatic means that do not use halogens as a means of functionalization. Herein, a halogenation strategy is presented to modify silk fibroin with the aim of developing a novel functional material through the carbon-halogen (C-X) bond. Modification with NaX (X = Cl, Br, and I) salts, hydrogen …


The F-Box Protein Fbw7 Negatively Regulates The Stability Of Erk3 Protein, Nicole Walters Jan 2021

The F-Box Protein Fbw7 Negatively Regulates The Stability Of Erk3 Protein, Nicole Walters

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Extracellular signal-regulated kinase 3 (ERK3) is a member of the atypical mitogen-activated protein kinase (MAPK) subfamily, whose members have been shown to play important roles in a number of cellular processes including proliferation, differentiation, migration, and apoptosis. While signals regulating ERK3 kinase activity remain unclear, ERK3 is known to be an unstable protein with function tightly regulated via ubiquitination and proteasomal turnover. The deubiquitinating enzyme USP20 has been shown to regulate ERK3 by stabilizing the kinase, but presently, no destabilizing ubiquitin ligases have been identified. The SKP1-CUL1-F-box protein (SCF) E3 ligases are a subfamily of ubiquitin E3 ligases composed of …


Quantitated Effects Of Nutritional Supplementation On Exercise Induced Sweat, Andrew Blake Austin Browder Jan 2021

Quantitated Effects Of Nutritional Supplementation On Exercise Induced Sweat, Andrew Blake Austin Browder

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Discovery studies have identified many metabolites contained in human sweat. However, quantitative analysis of the sweat metabolome content remains mostly unknown. Furthermore several attributes, including rate, have been defined to affect sweat metabolite content, while other effectors, like diet, remain unknown. This study works to quantitatively define the metabolite impact caused by nutritional supplementation. To better understand the effect diet plays, a LC-MS method was developed focusing on improving resolution and peak width. While the literature provided examples of how diet affected sweat metabolite concentrations, the long-term effects of diet have not been explored. The experiment described here attempts to …


Microsatellites And Their Association With Break Induced Replication, French J. Damewood Iv Jan 2021

Microsatellites And Their Association With Break Induced Replication, French J. Damewood Iv

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To study microsatellites instability and their repair pathways a dual fluorescent (DF2) and selectable (ganciclovir sensitive/ thymidine kinase (TK) expressing) cell system was assayed using replication fork stalling agents hydroxyurea and telomestatin. These cell lines carried ectopically integrated microsatellites derived from the Dystrophia Myotonica Protein Kinase (DMPK) gene ((CTG)102 microsatellite), or an 88 bp polypurine/ polypyrimidine (Pu/Py) repeat from the PKD-1 locus, inserted into a FLP recombinase target site. These microsatellites form non-B DNA structures in -vivo and in-vitro causing replication fork stalling and double strand breaks. DF2 myc (CTG)102 -TK cells treated with hydroxyurea were assayed for mutagenesis of …


Potential Drug Treatment For Duchenne Muscular Dystrophy Which Could Be Through Upregulation Of Lipin1, Rajsi Y. Thaker Jan 2021

Potential Drug Treatment For Duchenne Muscular Dystrophy Which Could Be Through Upregulation Of Lipin1, Rajsi Y. Thaker

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Duchenne muscular dystrophy (DMD) is a genetic disorder leading to progressive muscle degeneration and weakness due to mutation in dystrophin gene, which is very important for maintaining muscle membrane integrity. Dystrophin is the largest gene in the human genome therefore more prone to mutation. There is currently no cure for DMD. Our lab recently found that Lipin1 deficient myofibers showed upregulation of necroptosis correlated with the loss of muscle membrane integrity. Our primary approach for ameliorating dystrophic phenotype in DMD is through reduction of necroptosis using drugs which can potentially upregulate Lipin1 expression. In this study, we identified two drugs …


Alternative Splicing Of Mdm4 In Human Melanomas, Abdullah Salem S. Alatawi Jan 2020

Alternative Splicing Of Mdm4 In Human Melanomas, Abdullah Salem S. Alatawi

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Melanoma is a potentially lethal type of skin cancer and regarded to be the third most common type of skin cancer. Although melanoma is not as common as basal cell carcinoma (BCC) and squamous cell carcinoma (SCC), it is more likely to metastasize than BCC and SCC. Interestingly, the incidence of melanoma continues to go up (expected 2% in 2020), but the deaths continue to decrease (-5.3% in 2020) due to improvements in detection and treatment. The treatment of melanoma depends on several aspects but most importantly the tumor's stage and the location. In the early stages, melanoma can be …


Apoptosis And Necrosis Drive Muscle Fiber Loss In Lipin1 Deficient Skeletal Muscle, Sandhya Ramani Sattiraju Jan 2020

Apoptosis And Necrosis Drive Muscle Fiber Loss In Lipin1 Deficient Skeletal Muscle, Sandhya Ramani Sattiraju

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Mutations in lipin1 are suggested to be a common cause of massive rhabdomyolysis episodes in children, however, the molecular mechanism involved in the regulation of myofiber death by lipin1 is not known. In this study, we utilized the skeletal muscle from cell-type-specific lipin1 knockout (Lipin1Myf5cKO) mice to define cell death pathways involved in lipin1 deficient muscles. We observed a significant increase in centrally nucleated fibers and embryonic myosin heavy chain (EMyHC)-positive regenerating fibers in Lipin1Myf5cKO mice compared to wild-type (WT) mice, indicating an increased cycle of degeneration and regeneration in lipin1 deficient muscles. Lipin1 deficient muscles had significantly elevated pro-apoptotic …


Erk3 Negatively Regulates The Il-6/Stat3 Signaling Via Socs3, Astha Shakya Jan 2019

Erk3 Negatively Regulates The Il-6/Stat3 Signaling Via Socs3, Astha Shakya

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Mitogen activated protein kinases (MAPKs) are Ser/Thr kinases that relay the extracellular signal into intracellular responses and regulate several biological responses. They are classified into conventional MAPKs and atypical MAPKs. Extracellular signal regulated kinase 3 (ERK3) is an atypical MAPK that has a single phospho-acceptor site (Ser 189) in its activation motif instead of the canonical Thr-Xaa-Tyr (TXY) motif of conventional MAPK like ERK1/2. ERK3 comprises of a unique C terminal tail and a central C34 domain that further distinguishes it from ERK1/2. Moreover, compared to ERK1/2, much less is known about the upstream activators and the downstream targets of …


Genotyping For Response To Physical Training, Stacy Simmons Jan 2019

Genotyping For Response To Physical Training, Stacy Simmons

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Understanding the inter-individual variability in physical fitness performance has been the focus of scientific research for decades especially in the United States military. Injury and physical inadequacy cost the U.S military millions of dollars every year. The project PHITE (Precision High Intensity Training through Epigenetics) was funded to investigate this personal complex trait by combing the genetic and epigenetic (non-shared environmental factors) contributions into a single model for physical training response. This project is set up as having 150 male and female recruits between the ages of 18-27 years old. Each participant is randomly put blind into either a high …


∆Np63Α Positively Regulates Erk3 Expression In Non-Melanoma Skin Cancer, Eid Salem Alshammari Jan 2019

∆Np63Α Positively Regulates Erk3 Expression In Non-Melanoma Skin Cancer, Eid Salem Alshammari

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Non-melanoma skin cancer (NMSC) is a group of skin cancer that includes basal cell carcinoma of the skin (BCC), squamous cell carcinoma of the skin (SCC), actinic keratoses, a precursor to SCC, and other rare cutaneous carcinomas. p63, a member of the p53 gene family, is an important regulator for epithelial tissue growth and development. ∆Np63α, a main isoform of p63, is highly expressed in NMSC and plays essential roles in NMSCs development. Extracellular signal-regulated kinase 3 (ERK3) is an atypical member of the MAPK family. It possesses a single phosphorylation site (serine 189) in its activation loop, which makes …


Discovery Of Small Molecules Blocking Oncogenic K-Ras Activity, Sarah E. Kovar Jan 2018

Discovery Of Small Molecules Blocking Oncogenic K-Ras Activity, Sarah E. Kovar

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Ras proteins were the first human oncogenes discovered. Although Ras has been found to be the most frequently mutated oncogene, there are currently no anti-Ras-specific drugs available in the clinic. Ras is responsible for initiating cellular pathways that include proliferation, survival, and apoptosis. There are three ubiquitously expressed Ras isoforms in mammalian cells: H-, N-, and K-Ras. Interaction with the plasma membrane is required for Ras biological activity. When Ras interaction with the plasma membrane is blocked, Ras activity is inhibited. Two compounds (from Dr. Ketcha, WSU Chemistry Department) were tested and shown to dissociate K-Ras, but not H-Ras from …


Avicin Is A Potent Sphingomyelinase Inhibitor That Blocks K-Ras Plasma Membrane Interaction And Its Oncogenic Activity, Christian M. Garrido Jan 2018

Avicin Is A Potent Sphingomyelinase Inhibitor That Blocks K-Ras Plasma Membrane Interaction And Its Oncogenic Activity, Christian M. Garrido

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Ras proteins are small GTPases that regulate cell growth, differentiation and apoptosis. There are three main isoforms: H-, N-, and K-Ras in mammalian cells, and they cycle between an active GTP- and inactive GDP-bound states. Constitutively active Ras mutations are found in ~15% of all human cancers. Of those, oncogenic K-Ras is found in ~98% of pancreatic, ~52% colorectal, and ~32% of lung cancers. In nearly 30 years since its discovery, there are no anti-K-Ras drugs currently available for clinical use. Since K-Ras must be localized to the plasma membrane (PM) for its full biological activity, targeting K-Ras PM interaction …


Novel Insight Into The Role Of Lxrα In Metabolic Regulation Via Dna Binding As A Heterodimer With Pparα And As A Homodimer, Andrea M. Klingler Jan 2016

Novel Insight Into The Role Of Lxrα In Metabolic Regulation Via Dna Binding As A Heterodimer With Pparα And As A Homodimer, Andrea M. Klingler

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Liver X receptor a (LXRa) plays a critical role in the maintenance of energy homeostasis within a cell through tight transcriptional regulation of genes involved in metabolism of lipids, glucose, and cholesterol. Although LXRa has been established to function as a heterodimer with the retinoid X receptor a (RXRa), recent studies have determined that LXRa also interacts directly with peroxisome proliferator-activated receptor a (PPARa). However, little is known regarding the functionality of this heterodimer, if any exists at all. This study determined that a heterodimer of PPARa and LXRa is capable of binding to candidate response elements in vitro with …


Differences In Fecal Metabolite Profiles From Geographically Distinct Populations Of Adolescents, Jessica Moncivaiz Jan 2015

Differences In Fecal Metabolite Profiles From Geographically Distinct Populations Of Adolescents, Jessica Moncivaiz

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Microbiota of the gastrointestinal tract have a variety of functions within the human body. They participate in protection of the host from pathogens, aid in immune system development and regulation, and carry out a variety of metabolic functions. This study focuses on the ability of gut microbiota to create metabolites through the degradation of food products. Using 1H NMR on fecal water extracts, I compared the metabolite profiles of two geographically distinct cohorts: healthy adolescents from Egypt (n=28) and healthy adolescents from the United States (n=14). Multivariate statistical analyses of binned NMR data confirmed that samples separated into groups corresponding …


Lipase-Kinase Associations Involving Pld2, Jak3 And Fes That Underlie Cancer Cell Proliferation And Invasion, Qing Ye Jan 2012

Lipase-Kinase Associations Involving Pld2, Jak3 And Fes That Underlie Cancer Cell Proliferation And Invasion, Qing Ye

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Phospholipase D (PLD) is an enzyme that breaks down phospholipids in the cell membrane. It has been suggested that PLD may play a role during cell proliferation and cell invasion of cancer cells. The objective of this thesis was to define new molecular signaling pathways in which PLD2 might be involved in terms of cell proliferation (first part) and cell invasion (second part). To this, I compared molecular and biochemical aspects between untransformed cell lines with highly invasive, transformed breast cancer cells. In the first part, I investigated the interaction of two tyrosine kinases with PLD2 and the effect of …