Biochemistry, Biophysics, and Structural Biology Commons^™

Atg11 And Atg9 Interaction In Selective Autophagy, Chimi Dolker Sherpa

Master's Theses and Doctoral Dissertations

Selective autophagy, induced by cellular stresses, degrades/recycles a specific cargo. Ithelps prevent diseases like Parkinson’s, Huntington's, cancer, and bacterial infections. It involves the formation of an autophagosome, a double-membrane vesicle that takes the cargo to the vacuole/lysosome for degradation. Atg11, the central organizer of selective autophagy, acts as a scaffold protein, interacting with Atg9, Atg1 and other Atg proteins. Our research focuses on finding mutations in Atg11 that specifically disrupt its interaction with Atg9 without affecting its dimerization or interaction with Atg1. We targeted residues 455-535 of Atg11 as a putative Atg9 interaction site, performing mutagenesis on four key residues …

A Phytochemical Analysis Of Secondary Metabolites In Eupatorium Serotinum, Elise Snow

Theses and Dissertations

Phytochemistry, a subset of Natural Products Chemistry, studies chemically derived products from natural substances. Advances in this field have important applications in medicinal research due to the distinctive and unique properties of natural compounds. All metabolites are produced from the metabolic cycle, which is a pathway that provides energy for the organism. These metabolic compounds vary greatly and are classified based on their function within the organism. Primary metabolites are abundant and contribute to organism growth, development, and maintenance of energy. Secondary metabolites are found in lesser quantity and correlate to natural defense mechanisms. For example, salicylic acid is a …

Benzene Exposure In Reproductive Biology: A Comprehensive Analysis Of Placental Response And Molecular Mechanisms In Trophoblast Function, Anthony Maxwell

Wayne State University Dissertations

The increase in environmental challenges and exposure to pollutants like benzene poses pressing concerns for reproductive health. This dissertation investigates the impact of benzene exposure during gestation on placental function, a key determinant for fetal development and pregnancy outcomes. Our work establishes that benzene exposure during pregnancy induces maternal immune activation, leading to increased rates of fetal resorptions, compromised fetal growth, and abnormal placental development. Intriguingly, we identify a sexual dimorphic response in male and female placentas to benzene exposure, attributable to inherent differences between male and female placental biology. On a molecular level, benzene is metabolized into hydroquinone in …

Excited State Proton Transfer From Acidic Alcohols To A Quinoline Photobase Can Be Solvated By Non-Acidic Alcohol Solvents, Jonathan Ryan Hunt, Joseph Hecht, Clara Goolsby, Jade Hagihara, Monique Loza, Samantha Del Pozo

Chemistry and Biochemistry Faculty Works

Photobases are a type of molecule that become more basic upon photoexcitation and can therefore be used to control proton transfer reactions with light. The solvation requirements for excited state proton transfer (ESPT) in photobase systems is poorly understood, which limits their applicability. Here, we investigate the solvation of the ESPT reaction using 5-methoxyquinoline (MeOQ), a well-studied photobase with an excited state pKa (pKa*) of approximately 15.1, as a model system. Previous studies have shown that, in addition to the acidic donor that donates a proton to the photoexcited MeOQ, an additional “auxiliary donor” is necessary to solvate the resulting …

The Role Of Sugars In Aggregation Of The Protein Kassinin, Lillie G. Waldron

Student Summer Scholars Manuscripts

The aggregation of proteins to form amyloids is implicated in several diseases such as Alzheimer’s Disease, Parkinson’s Disease, and many others. This aggregation has several stages, progressing from isolated protein molecules (monomers) to small aggregates (oligomers), which are toxic to cells, and finally to large, string-like mature aggregates. Despite this association with disease, functional amyloids, which have normal biological functions, also result from protein aggregation. Kassinin, an amphibian peptide involved in nerve signal transmission, is a model system for functional amyloid study. To compare the aggregation of functional and disease-causing amyloids, we previously synthesized a fluorine-labeled kassinin through solid-phase peptide …

Emerging Chromatin Regulators In Response To Heavy Metal Exposure, Wesley Saintilnord

Theses and Dissertations--Molecular and Cellular Biochemistry

Environmental exposure to heavy metals poses significant threats to human health as they are associated with various developmental and chronic pathologies such as reproductive defects and cancers. Despite their profound risks, a comprehensive understanding of their disease-causing mechanisms is lacking. Most studies point to reactive oxygen species-induced DNA damage; however, their mutagenic potential is relatively weak suggesting the involvement of alternative mechanisms. One important, yet underexplored mechanism, is their ability to rewire the epigenome via DNA methylation and histone variant incorporation, leading to aberrant gene regulatory networks.

This study investigates the epigenetic mechanisms targeted by two ubiquitous heavy metals with …

Exploring The Effects Of Choline Treatment On Dystrophic Phenotype, Brooklyn Morris

Browse all Theses and Dissertations

Duchenne Muscular Dystrophy (DMD) is a devastating progressive muscular disorder caused by a mutation in the dystrophin gene affecting approximately 1 in 3,500 males. However, despite its prevalence, there is currently no cure for this disease. Mutations in dystrophin lead to enhanced inflammation, fibrosis, cell death, development, and decreased skeletal muscle function. Phosphatidylcholine, synthesized by choline, is a major phospholipid that functions in maintaining and synthesizing cell membranes and has previously been found to be decreased in DMD patients. This led us to hypothesize that the dystrophic phenotype could be improved through treatment with choline. In this study, we used …

Exploring The Molecular Pathways Of Cell Death Induced By Pde3 Modulators, Aqsa Ahsan

Dissertations, Master's Theses and Master's Reports

Metabolic dysregulation, a critical hallmark of cancer, predisposes potential vulnerabilities for the development of targeted therapy. LKB1, a pivotal metabolic regulator and tumor suppressor, is often lost in many cancers. Our laboratory has unveiled that LKB1 suppresses phosphodiesterases (PDEs), and PDE3 modulators can selectively eradicate LKB1-deficient tumor cells. Through metabolic gene sgRNA library screening, Sarcolipin, an inhibitor of Sarcoendoplasmic Reticulum Calcium ATPase (SERCA), emerged as essential for cell death in this context. However, the precise molecular mechanisms by which PDE3 modulators exert their effects remain elusive. This study aims to uncover these mechanisms via RNA-Seq profiling and differential gene analysis, …

Hybridization Kinetics Of Four-Way Junctions Localized On A Dna Scaffold, Katherine N. Taylor

Honors Undergraduate Theses

DNA computing is an ever-growing field with scientists trying to design structures that optimize logic gate communication to develop fast, biologically compatible, computational structures. We hypothesize that by using the principles of DNA computing, it is possible to design a DNA tile capable of studying localized DNA hybridization that can differentiate between oligonucleotides of different structural conformations. This includes synthetically manipulating DNA into a nanostructure that can perform Boolean logic functions to calculate the different rates of hybridization. To test our hypothesis, we designed a DNA Tile that incorporated a 4WJ using YES logic. Linear and hairpin single-stranded (ss) DNA …

The Evolution Of The Metazoan Circadian Molecular Mechanism And The Conservation Of Canonical Circadian Elements, Olivia Waldridge

Theses and Dissertations--Biology

The temporal organization of biological activities through circadian rhythms is pivotal for the survival of organisms. Significant progress has been made in understanding the molecular foundations of animal circadian clocks through the characterization of key components such as Clock, Bmal1/Cycle(Cyc), Period (Per), Timeless, and Cryptochrome (Cry) in several model organisms. To determine the universality of this conservation, we investigated the sequences of these genes and their paralogs across 46 animal species that encompass multiple phyla in the metazoan kingdom to resolve the relative timing of duplication and loss events that have diversified core clock components in the metazoan kingdom. Using …

The Carboxy Terminus Causes Interfacial Assembly Of Oleate Hydratase On A Membrane Bilayer, Christopher D. Radka, Christy R. Grace, Hale S. Hasdemir, Yupeng Li, Carlos C. Rodriguez, Patrick Rodrigues, Michael L. Oldham, M. Zuhaib Qayyum, Aaron Pitre, William J. Maccain, Ravi C. Kalathur, Emad Tajkhorshid, Charles O. Rock

Markey Cancer Center Faculty Publications

The soluble flavoprotein oleate hydratase (OhyA) hydrates the 9-cis double bond of unsaturated fatty acids. OhyA sub- strates are embedded in membrane bilayers; OhyA must remove the fatty acid from the bilayer and enclose it in the active site. Here, we show that the positively charged helix- turn-helix motif in the carboxy terminus (CTD) is responsible for interacting with the negatively charged phosphatidylgly- cerol (PG) bilayer. Super-resolution microscopy of Staphylo- coccus aureus cells expressing green fluorescent protein fused to OhyA or the CTD sequence shows subcellular localization along the cellular boundary, indicating OhyA is membrane- associated and the CTD sequence …

Strategies For Improving The Performance Of Prediction Models For Response To Immune Checkpoint Blockade Therapy In Cancer, Tiantian Zeng, Jason Z. Zhang, Arnold Stromberg, Jin Chen, Chi Wang

Markey Cancer Center Faculty Publications

Immune checkpoint blockade (ICB) therapy holds promise for bringing long-lasting clinical gains for the treatment of cancer. However, studies show that only a fraction of patients respond to the treatment. In this regard, it is valu- able to develop gene expression signatures based on RNA sequencing (RNAseq) data and machine learning meth- ods to predict a patient’s response to the ICB therapy, which contributes to more personalized treatment strategy and better management of cancer patients. However, due to the limited sample size of ICB trials with RNAseq data available and the vast number of candidate gene expression features, it is …

Vaginal Lactobacillus Fatty Acid Response Mechanisms Reveal A Metabolite-Targeted Strategy For Bacterial Vaginosis Treatment, Paul C. Blainey, Seth M. Bloom, Douglas S. Kwon

Markey Cancer Center Faculty Publications

Bacterial vaginosis (BV), a common syndrome characterized by Lactobacillus-deficient vaginal microbiota, is associated with adverse health outcomes. BV often recurs after standard antibiotic therapy in part because antibiotics promote microbiota dominance by Lactobacillus iners instead of Lactobacillus crispatus, which has more beneficial health associations. Strategies to promote L. crispatus and inhibit L. iners are thus needed. We show that oleic acid (OA) and similar long-chain fatty acids simultaneously inhibit L. iners and enhance L. crispatus growth. These phenotypes require OA-inducible genes conserved in L. crispatus and related lactobacilli, including an oleate hydratase (ohyA) and putative fatty acid efflux pump (farE). …

Elevated Free Cholesterol Levels Due To Impaired Reverse Cholesterol Transport Are A Risk Factor For Polymicrobial Sepsis In Mice, Qian Wang, Ling Guo, Dan Hao, Misa Ito, Chieko Mineo, Philip W. Shaul, Xiang-An Li

Markey Cancer Center Faculty Publications

Dysregulated lipid metabolism is commonly observed in septic patients, but how it contributes to sepsis remains largely unknown. Reverse cholesterol transport (RCT) is crucial for regulating cholesterol metabolism in circulation. During RCT, high-density lipoprotein collects cholesterol from peripheral tissues and transports it to the liver’s scavenger receptor BI (SR- BI), where SR-BI mediates the uptake of cholesteryl esters (CEs) from high-density lipoprotein for excretion via bile. In this study, we utilized AlbCreSR-BIfl/fl mice, a model with impaired RCT, to investigate the impact of RCT on sepsis. We found that AlbCreSR-BIfl/fl mice were significantly more susceptible to cecal ligation and puncture …

Nudcl2 Is Required For Cytokinesis By Stabilizing Rcc2 With Hsp90 At The Midbody, Xiaoyang Xu, Yuliang Huang, Feng Yang, Xiaoxia Sun, Rijin Lin, Jiaxing Feng, Mingyang Yang, Jiaqi Shao, Xiaoqi Liu, Tianhua Zhou, Shanshan Xie, Yuehong Yang

Markey Cancer Center Faculty Publications

Cytokinesis is required for faithful division of cytoplasmic components and duplicated nuclei into two daughter cells. Midbody, a protein-dense organelle that forms at the intercellular bridge, is indispensable for success- ful cytokinesis. However, the regulatory mechanism of cytokinesis at the midbody still remains elusive. Here, we unveil a critical role for NudC-like protein 2 (NudCL2), a co-chaperone of heat shock protein 90 (Hsp90), in cytokinesis regulation by stabilizing regulator of chromosome condensation 2 (RCC2) at the midbody in mam- malian cells. NudCL2 localizes at the midbody, and its downregulation results in cytokinesis failure, multinu- cleation, and midbody disorganization. Using iTRAQ-based …

Enhancing Translation: A Need To Leverage Complex Preclinical Models Of Addictive Drugs To Accelerate Substance Use Treatment Options, Christa Corley, Ashley Craig, Safiyah M. Sadek, Julie A. Marusich, Samar N. Chehimi, Ashley M. White, Lexi J. Holdiness, Benjamin C. Reiner, Cassandra D. Gipson

Markey Cancer Center Faculty Publications

Preclinical models of addictive drugs have been developed for decades to model aspects of the clinical experience in substance use disorders (SUDs). These include passive exposure as well as volitional intake models across addictive drugs and have been utilized to also measure withdrawal symptomatology and potential neuro- behavioral mechanisms underlying relapse to drug seeking or taking. There are a number of Food and Drug Administration (FDA)-approved medications for SUDs, however, many demonstrate low clinical efficacy as well as potential sex differences, and we also note gaps in the continuum of care for certain aspects of clinical ex- periences in individuals …

Biliverdin Reductase-A Integrates Insulin Signaling With Mitochondrial Metabolism Through Phosphorylation Of Gsk3Β, Chiara Lanzillotta, Antonella Tramutola, Simona Lanzillotta, Viviana Greco, Sara Pagnotta, Caterina Sanchini, Silvia Di Angelantonio, Elena Forte, Serena Rinaldo, Alessio Paone, Francesca Cutruzzolà, Flavia Agata Cimini, Ilaria Barchetta, Maria Gisella Cavallo, Andrea Urbani, D. Allan Butterfield, Fabio Di Domenico, Bindu D. Paul, Marzia Perluigi, Joao M.N. Duarte

Markey Cancer Center Faculty Publications

Brain insulin resistance links the failure of energy metabolism with cognitive decline in both type 2 Diabetes Mellitus (T2D) and Alzheimer’s disease (AD), although the molecular changes preceding overt brain insulin resistance remain unexplored. Abnormal biliverdin reductase-A (BVR-A) levels were observed in both T2D and AD and were associated with insulin resistance. Here, we demonstrate that reduced BVR-A levels alter insulin signaling and mitochondrial bioenergetics in the brain. Loss of BVR-A leads to IRS1 hyper-activation but dys- regulates Akt-GSK3β complex in response to insulin, hindering the accumulation of pGSK3βS9 into the mito- chondria. This event impairs oxidative phosphorylation and fosters …

Therapeutic Potential Of Berberine In Attenuating Cholestatic Liver Injury: Insights From A Psc Mouse Model, Yanyan Wang, Derrick Zhao, Lianyong Su, Yun-Ling Tai, Grayson W. Way, Jing Zeng, Qianhua Yan, Ying Xu, Xuan Wang, Emily C. Gurley, Xi-Qiao Zhou, Jinze Liu, Jinpeng Liu, Weidong Chen, Philip B. Hylemon, Huiping Zhou

Markey Cancer Center Faculty Publications

Background and aims

Primary sclerosing cholangitis (PSC) is a chronic liver disease characterized by progressive biliary inflammation and bile duct injury. Berberine (BBR) is a bioactive isoquinoline alkaloid found in various herbs and has multiple beneficial effects on metabolic and inflammatory diseases, including liver diseases. This study aimed to examine the therapeutic effect of BBR on cholestatic liver injury in a PSC mouse model (Mdr2 −/− mice) and eluci‑ date the underlying mechanisms.

Methods

Mdr2−/− mice (12–14 weeks old, both sexes) received either BBR (50 mg/kg) or control solution daily for eight weeks via oral gavage. Histological and serum biochemical …

Mechanisms Of Γδ T Cell Accumulation In Visceral Adipose Tissue With Aging, Sujata Mukherjee, Maria E. C. Bruno, Jason Oakes, Gregory S. Hawk, Arnold Stromberg, Donald A. Cohen, Marlene E. Starr

Markey Cancer Center Faculty Publications

γδ T cells are resident in visceral adipose tissue (VAT) where they show an age- associated increase in numbers and contribute to local and systemic chronic inflammation. However, regulation of this population and mechanisms for the age-dependent accumulation are not known. In this study, we identified a progressive trend of γδ T cell accumulation in VAT over the lifespan in mice and explored physiological mechanisms contributing to accumulation. Using isochronic parabiotic pairs of wild-type (WT) and T cell receptor delta knockout (TCRδ KO) mice at young and old age, we confirmed that VAT γδ T cells are predominately a tissue-resident …

A Novel Protozoa Parasite-Derived Protein Adjuvant Is Effective In Immunization With Cancer Cells To Activate The Cancer-Specific Protective Immunity And Inhibit The Cancer Growth In A Murine Model Of Colorectal Cancer, Rajesh Mani, Chloe G. Martin, Kanal E. Balu, Qingding Wang, Piotr G. Rychahou, Tadahide Izumi, B. Mark Evers, Yasuhiro Suzuki

Markey Cancer Center Faculty Publications

Cancer-specific CD8+ cytotoxic T cells play important roles in preventing cancer growth, and IFN-γ, in addition to IL-12 and type I interferon, is critical for activating CD8+ cytotoxic T cells. We recently identified the capability of the amino-terminus region of dense granule protein 6 (GRA6Nt) of Toxoplasma gondii, an intracellular protozoan parasite, to activate IFN-γ production of microglia, a tissue-resident macrophage population. Therefore, in the present study, we examined whether recombinant GRA6Nt protein (rGRA6Nt) functions as an effective adjuvant to potently activate cancer-specific protective immunity using a murine model of MC38 colorectal cancer (CRC). When mice were immunized with non-replicable …