Biochemistry Commons^™

A Review Of Rheb Activation Of Mtorc1 And The Great Mystery Of One Missing Gef, Jack Gregory

Senior Honors Theses

The mTORC1 pathway is involved in the regulation of cell growth and translation. The pathway has a complex web of activators and inhibitors to activate mTORC1. mTORC1 is regulated via a small GTPase called Rheb, which interacts directly with mTORC1. This GTPase and its GTPase activating protein (GAP), TSC1/2, have been widely studied to understand how the variety of regulators of mTORC1 interact with these proteins. Despite this, the guanine nucleotide exchange factor (GEF) of Rheb has yet to be identified. This review broadly analyzes Rheb and mTORC1, their structures, regulations, and interactions, and explores the mystery of the missing …

A Combination Of Generated Hydrogen Sulfide And Nitric Oxide Activity Has A Potentiated Protectant Effect Against Cisplatin Induced Nephrotoxicity, Faria Khurshid, Javeid Iqbal, Fiaz Ud Din Ahmad, Arslan Hussain Lodhi, Abdul Malik, Suhail Akhtar, Azmat Ali Khan, Marvi Imam Bux, Mohammed Younis

Biomedical Sciences Faculty Publications

Aim: Hydrogen sulfide and nitricoxide possess cytoprotective activity and in vivo, they are generated from exogenous sodium hydrosulfide and L-arginine respectively. Cisplatin is a major chemotherapeutic agent used to treat cancer and has a high incidence of nephrotoxicity as a side effect. The study aim was to explore the effects of NaHS and L-arginine or their combination on cisplatin induced nephrotoxicity in rats. Methods: Wistar Kyoto rats were given a single intraperitoneal dose of cisplatin (5 mg/kg) followed either by NaHS (56 μmol/kg, i. p.), L-arginine (1.25 g/L in drinking water) or their combination daily for 28-days. Post-mortem plasma, urine …

The Purification And Thermal Stability Of The Peroxidase Enzyme In Cucurbita Moschata, Garen Hamner

Senior Honors Theses

Peroxidases are enzymes that catalyze the reduction of hydrogen peroxide to water while oxidizing organic substrates and are valuable in spheres like industrial and medical applications and histochemistry. Limitations still exist in the use of the well-studied horseradish peroxidase for certain activities due to limitations like poor thermal stability, thus the search for novel peroxidases that can overcome these limitations is an active area of research. Butternut squash peroxidase (Cucurbita moschata) (BSP) shows promise due to significant activity being found in the skin and apparent enhanced thermal stability, but an efficient purification scheme for it is lacking, as well as …

Discovery Of A Small-Molecule Inhibitor That Traps Polθ On Dna And Synergizes With Parp Inhibitors, William Fried, Mrityunjay Tyagi, Leonid Minakhin, Gurushankar Chandramouly, Taylor Tredinnick, Mercy Ramanjulu, William Auerbacher, Marissa L Calbert, Timur Rusanov, Trung Hoang, Nikita Borisonnik, Robert Betsch, John Krais, Yifan Wang, Umeshkumar Vekariya, John Gordon, George Morton, Tatiana Kent, Tomasz Skorski, Neil Johnson, Wayne Childers, Xiaojiang Chen, Richard Pomerantz

Department of Biochemistry and Molecular Biology Faculty Papers

The DNA damage response (DDR) protein DNA Polymerase θ (Polθ) is synthetic lethal with homologous recombination (HR) factors and is therefore a promising drug target in BRCA1/2 mutant cancers. We discover an allosteric Polθ inhibitor (Polθi) class with 4-6 nM IC₅₀ that selectively kills HR-deficient cells and acts synergistically with PARP inhibitors (PARPi) in multiple genetic backgrounds. X-ray crystallography and biochemistry reveal that Polθi selectively inhibits Polθ polymerase (Polθ-pol) in the closed conformation on B-form DNA/DNA via an induced fit mechanism. In contrast, Polθi fails to inhibit Polθ-pol catalytic activity on A-form DNA/RNA in which the enzyme binds in …

Parp2 Promotes Break Induced Replication-Mediated Telomere Fragility In Response To Replication Stress, Daniela Muoio, Natalie Laspata, Rachel L Dannenberg, Caroline Curry, Simone Darkoa-Larbi, Mark Hedglin, Shikhar Uttam, Elise Fouquerel

Department of Biochemistry and Molecular Biology Faculty Papers

PARP2 is a DNA-dependent ADP-ribosyl transferase (ARTs) enzyme with Poly(ADP-ribosyl)ation activity that is triggered by DNA breaks. It plays a role in the Base Excision Repair pathway, where it has overlapping functions with PARP1. However, additional roles for PARP2 have emerged in the response of cells to replication stress. In this study, we demonstrate that PARP2 promotes replication stress-induced telomere fragility and prevents telomere loss following chronic induction of oxidative DNA lesions and BLM helicase depletion. Telomere fragility results from the activity of the break-induced replication pathway (BIR). During this process, PARP2 promotes DNA end resection, strand invasion and BIR-dependent …

Blocking The Dimerization Of Polyglutamine-Expanded Androgen Receptor Protects Cells From Dht-Induced Toxicity By Increasing Ar Turnover, Allison Lisberg, Yuhong Liu, Diane E. Merry

Department of Biochemistry and Molecular Biology Faculty Papers

Spinal and bulbar muscular atrophy (SBMA) is a neuromuscular degenerative disease caused by a polyglutamine expansion in the androgen receptor (AR). This mutation causes AR to misfold and aggregate, contributing to toxicity in and degeneration of motor neurons and skeletal muscle. There is currently no effective treatment or cure for this disease. The role of an interdomain interaction between the amino- and carboxyl-termini of AR, termed the N/C interaction, has been previously identified as a component of androgen receptor-induced toxicity in cell and mouse models of SBMA. However, the mechanism by which this interaction contributes to disease pathology is unclear. …

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 …

The Effect Of Ethanol Treatment On The Protein Content Of Difi Exosomes, Kenzie Rushing

Belmont University Research Symposium (BURS)

Colorectal cancer (CRC) is the second most common cause of cancer death in the United States in both men and women combined, second only to lung cancer.1 CRC metastasis is the primary cause of mortality largely due to therapy resistant cancer cells.2 Therefore, detection before metastasis is of great importance and could potentially lead to earlier detection and decreased mortality. Extracellular vesicles (EVs), including exosomes, are lipid bound vesicles secreted by cells3 that are involved in cell-cell communication and have been found to promote CRC progression and metastasis.4 The proteome of exosomes is thought to reflect that of the originating …

Differentially Disrupted Spinal Cord And Muscle Energy Metabolism In Spinal And Bulbar Muscular Atrophy, Danielle Debartolo, Frederick Arnold, Y Liu, Elana Molotsky, Hsin-Yao Tang, Diane Merry

Department of Biochemistry and Molecular Biology Faculty Papers

Prior studies showed that polyglutamine-expanded androgen receptor (AR) is aberrantly acetylated and that deacetylation of the mutant AR by overexpression of nicotinamide adenine dinucleotide-dependent (NAD+-dependent) sirtuin 1 is protective in cell models of spinal and bulbar muscular atrophy (SBMA). Based on these observations and reduced NAD+ in muscles of SBMA mouse models, we tested the therapeutic potential of NAD+ restoration in vivo by treating postsymptomatic transgenic SBMA mice with the NAD+ precursor nicotinamide riboside (NR). NR supplementation failed to alter disease progression and had no effect on increasing NAD+ or ATP content in muscle, despite producing a modest increase of …

Raw Nmr Data For Tripeptides, David J. Michaelis, Scott R. Burt, Mariur Rodriguez Moreno, Nye C. Johnson, Christopher B. Stewart, Mary L. Setelin, Adam X. Wayment, Braxton M. Felix

ScholarsArchive Data

This data set contains primary data for 50 tripeptides that were generated as part of an advanced undergraduate laboratory experience in solid phase peptide synthesis. The raw data can be processed sing NMR interpretation software and can be used as problems for exams and quizzes or as supplementary materials for a laboratory experience

Editorial: Pharmacology Of Endocrine Related Gpcrs, Francesco De Pascali, Aylin Hanyaloglu, Frederic Jean-Alphonse, Francesco Potì, Eric Reiter

Department of Biochemistry and Molecular Biology Faculty Papers

No abstract provided.

Historical Ozone Isopleths For Salt Lake Valley, Ut, Usa, Callum Flowerday, Isaac Sudweeks, Brad Adams, Jaron C. Hansen

ScholarsArchive Data

EPA quality assured data, collected by the Utah Division of Air Quality, was used for this analysis.

Historical Analysis Of Urban Dust Generated By The Great Salt Lake Playa, Callum Flowerday, Jaron C. Hansen, Rebekah Stanley, Kaitlyn Brewster

ScholarsArchive Data

Historical PM10 filters, provided by the Utah Division of Air Quality, were analyzed for elemental composition of various metals. This was done using ICP-MS.

Also included, EPA PM10 historical data and bathymetry data provided by the Utah USGS.

Unimer Suppression Enables Supersaturated Homopolymer Swollen Micelles With Long-Term Stability After Glassy Entrapment, Eric R. Williams, Christian X. Ruff, Morgan Stefik

Faculty Publications

Micelle sizes are critical for a range of applications where the simple ability to adjust and lock in specific stable sizes has remained largely elusive. While micelle swelling agents are well-known, their dynamic re-equilibration in solution implies limited stability. Here, a non-equilibrium processing sequence is studied where supersaturated homopolymer swelling is combined with glassy-core (“persistent”) micelles. This path-dependent process was found to sensitively depend on unimer concentration as revealed by DLS, SAXS, and TEM analysis. Here, lower-selectivity solvent combinations led to the formation of unimer-homopolymer aggregates and eventual precipitation, reminiscent of anomalous micellization. In contrast, higher-selectivity solvents enabled supersaturated homopolymer …

Studying The Genes And Conditions That Influence Root Development, Tessa Holtkamp, Hannah Ordonez Webb

Undergraduate Research Symposium

Root development in plants is essential for their survival and understanding how hormones influence their development can explain how plants grow under different circumstances. Researching how Indole-3-butyric acid (IBA), a hormone that induces root production, affects the plant model Arabidopsis thaliana helps explain the hormone's effect in agricultural crop systems. To understand root pathways, we performed assays on mutant lines of Arabidopsis by growing plants on varying concentrations of IBA. For wild-type and mutant lines, phenotyping experiments like branching of roots, lengths of stems, and root length were conducted along with PCR and restriction digest genotyping experiments to compare their …

Investigation Of Alzheimer’S Amyloid-Β Protein Aggregation With A New Fluorescent Dye., Emma Alberty

Undergraduate Research Symposium

Alzheimer’s Disease (AD) is the most common form of dementia characterized by the impairment of at least two brain functions such as memory loss and judgement. AD is a progressive illness that can last as many as 20 years. AD is largely considered to be caused by the formation of extracellular amyloid plaques and intracellular neurofibrillary tangles. A better understanding of the structure and function of these plaques may lead to clearer understanding of the disease. To analyze amyloid plaques, aggregation assays are often used. During these assays we begin with monomer and place the sample in biological conditions to …

Course Portfolio For Biochemistry 1: Structure And Metabolism (Bioc431), Didier Mena

UNL Faculty Course Portfolios

This benchmark portfolio encapsulates a comprehensive exploration aimed at enhancing the educational landscape of the BIOC431 course, a part of the general biochemistry course series (431 and 432). These courses are designed to offer a general introduction to the structure and function of cells in the body, along with their chemical reactions. Specifically, BIOC431 focuses on the structure, function, and metabolism of proteins, lipids, carbohydrates, and other major metabolic pathways. The three primary objectives addressed in this portfolio were the reevaluation of learning objectives, reassessment of assessment methods, and documentation of effective classroom strategies. Through background design, the learning objectives …

Tail-Tape-Fused Virion And Non-Virion Rna Polymerases Of A Thermophilic Virus With An Extremely Long Tail, Anastasiia Chaban, Leonid Minakhin, Ekaterina Goldobina, Brain Bae, Yue Hao, Sergei Borukhov, Leena Putzeys, Maarten Boon, Florian Kabinger, Rob Lavigne, Kira Makarova, Eugene V Koonin, Satish Nair, Shunsuke Tagami, Konstantin Severinov, Maria Sokolova

Department of Biochemistry and Molecular Biology Faculty Papers

Thermus thermophilus bacteriophage P23-45 encodes a giant 5,002-residue tail tape measure protein (TMP) that defines the length of its extraordinarily long tail. Here, we show that the N-terminal portion of P23-45 TMP is an unusual RNA polymerase (RNAP) homologous to cellular RNAPs. The TMP-fused virion RNAP transcribes pre-early phage genes, including a gene that encodes another, non-virion RNAP, that transcribes early and some middle phage genes. We report the crystal structures of both P23-45 RNAPs. The non-virion RNAP has a crab-claw-like architecture. By contrast, the virion RNAP adopts a unique flat structure without a clamp. Structure and sequence comparisons of …