Biochemistry, Biophysics, and Structural Biology Commons^™

Tellurite Resistance In Shiga Toxin-Producing Escherichia Coli , Gentry L. Lewis, Quentin R. Jorgensen, John Dustin Loy, Rodney A. Moxley

School of Veterinary and Biomedical Sciences: Faculty Publications

Potassium tellurite ( K₂TeO₃) is an effective selective agent for O157:H7 Shiga toxin-producing Escherichia coli (STEC), whereas tellurite resistance in non-O157 STEC is variable with information on O45 minimal. High-level K₂TeO₃ resistance in STEC is attributable to the ter gene cluster with terD an indicator of the cluster’s presence. Polymerase chain reactions for terD and K₂TeO₃ minimum inhibitory concentration (MIC) determinations in broth cultures were conducted on 70 STEC and 40 non-STEC control organisms. Sixty-six STEC strains (94.3%) were terD+ compared to 28 control organisms (70.0%; P < 0.001). The prevalence of terD in …

Epitope Mapping Of Serca2a Identifies An Antigenic Determinant That Induces Mainly Atrial Myocarditis In A/J Mice, Bharathi Krishnan, Chandirasegara Massilamany, Rakesh H. Basavalingappa, Arunakumar Gangaplara, Rajkumar Rajasekaran, Muhammad Z. Afzal, Vahid Khalilzad-Sharghi, You Zhou, Jean-Jack Riethoven, Shyam S. Nandi, Paras K. Mishra, Raymond A. Sobel, Jennifer L. Strande, David Steffen, Jay Reddy

School of Veterinary and Biomedical Sciences: Faculty Publications

Sarcoplasmic/endoplasmic reticulum Ca²⁺ adenosine triphosphatase (SERCA)2a, a critical regulator of calcium homeostasis, is known to be decreased in heart failure. Patients with myocarditis or dilated cardiomyopathy develop autoantibodies to SERCA2a suggesting that they may have pathogenetic significance. In this report, we describe epitope mapping analysis of SERCA2a in A/J mice that leads us to make five observations: 1) SERCA2a contains multiple T cell epitopes that induce varying degrees of myocarditis. One epitope, SERCA2a 971–990, induces widespread atrial inflammation without affecting noncardiac tissues; the cardiac abnormalities could be noninvasively captured by echocardiography, electrocardiography, and magnetic resonance microscopy imaging. 2) SERCA2a …

Total Mercury Determination In Muscle And Liver Tissue Samples From Brazilian Amazon Fish Using Slurry Sampling, João Vitor De Queiroz, José Cavalcante Souza Vieira, Izabela Da Cunha Bataglioli, Alis Correia Bittarello, Camila Pereira Braga, Grasieli De Oliveira, Cilene Do Carmo Federici Padilha, Pedro De Magalhães Padilha

Department of Biochemistry: Faculty Publications

This paper presents a slurry sampling method for total mercury determination by graphite furnace atomic absorption spectrometry (GFAAS) in tissue of fish from the Amazon. The tissue samples were lyophilized and macerated, and then the slurry samples were prepared by putting 20 mg of tissue, added to a solution containing Triton X-100, Suprapur HNO₃, and zirconium nitrate directly in sampling vials of a spectrometer. Mercury standard solutions were prepared under the same conditions as the slurry samples. The slurry samples and the mercury standard solutions were sonicated for 20 s. Twenty microliters of slurry samples were injected into …

Cancerdiscover: An Integrative Pipeline For Cancer Biomarker And Cancer Class Prediction From High-Throughput Sequencing Data, Akram Mohammed, Greyson Biegert, Jiri Adamec, Tomáš Helikar

Department of Biochemistry: Faculty Publications

Accurate identification of cancer biomarkers and classification of cancer type and subtype from High Throughput Sequencing (HTS) data is a challenging problem because it requires manual processing of raw HTS data from various sequencing platforms, quality control, and normalization, which are both tedious and timeconsuming. Machine learning techniques for cancer class prediction and biomarker discovery can hasten cancer detection and significantly improve prognosis. To date, great research efforts have been taken for cancer biomarker identification and cancer class prediction. However, currently available tools and pipelines lack flexibility in data preprocessing, running multiple feature selection methods and learning algorithms, therefore, developing …

Towards The Synthetic Design Of Camelina Oil Enriched In Tailored Acetyl-Triacylglycerols With Medium-Chain Fatty Acids, Sunil Bansal, Hae Jin Kim, Gunnam Na, Megan E. Hamilton, Edgar B. Cahoon, Chaofu Lu, Timothy P. Durrett

Department of Biochemistry: Faculty Publications

The ability to manipulate expression of key biosynthetic enzymes has allowed the development of genetically modified plants that synthesise unusual lipids that are useful for biofuel and industrial applications. By taking advantage of the unique activities of enzymes from different species, tailored lipids with a targeted structure can be conceived. In this study we demonstrate the successful implementation of such an approach by metabolically engineering the oilseed crop Camelina sativa to produce 3-acetyl-1,2-diacyl-sn-glycerols (acetyl-TAGs) with medium-chain fatty acids (MCFAs). Different transgenic camelina lines that had been genetically modified to produce MCFAs through the expression of MCFA-specific thioesterases and …

Single-Molecule Unbinding Forces Between The Polysaccharide Hyaluronan And Its Binding Proteins, Fouzia Bano, Markku I. Tammi, David W. Kang, Edward N. Harris, Ralf P. Richter

Department of Biochemistry: Faculty Publications

The extracellular polysaccharide hyaluronan (HA) is ubiquitous in all vertebrate tissues, where its various functions are encoded in the supramolecular complexes and matrices that it forms with HA-binding proteins (hyaladherins). In tissues, these supramolecular architectures are frequently subjected to mechanical stress, yet how this affects the intermolecular bonding is largely unknown. Here, we used a recently developed single-molecule force spectroscopy platform to analyze and compare the mechanical strength of bonds between HA and a panel of hyaladherins from the Link module superfamily, namely the complex of the proteoglycan aggrecan and cartilage link protein, the proteoglycan versican, the inflammation-associated protein TSG-6, …

Endosomal Escape Of Antisense Oligonucleotides Internalized By Stabilin Receptors Is Regulated By Rab5c And Eea1 During Endosomal Maturation, Colton M. Miller, W. Brad Wan, Punit P. Seth, Edward N. Harris

Department of Biochemistry: Faculty Publications

Second-generation (Gen 2) Antisense oligonucleotides (ASOs) show increased nuclease stability and affinity for their RNA targets, which has translated to improved potency and therapeutic index in the clinic. Gen 2 ASOs are typically modified using the phosphorothioate (PS) backbone modification, which enhances ASO interactions with plasma, cell surface, and intracellular proteins. This facilitates ASO distribution to peripheral tissues and also promotes cellular uptake after injection into animals. Previous work identified that Stabilin receptors specifically internalize PS-ASOs in the sinusoidal endothelial cells of the liver and the spleen. By modulating expression of specific proteins involved in the trafficking and maturation of …

Purification Of Hepatocytes And Sinusoidal Endothelial Cells From Mouse Liver Perfusion, Fatima Cabral, Colton M. Miller, Katrina M. Kudrna, Blake E. Hass, Jocelyn G. Daubendiek, Brianna M. Kellar, Edward N. Harris

Department of Biochemistry: Faculty Publications

This protocol demonstrates a method for obtaining high yield and viability for mouse hepatocytes and sinusoidal endothelial cells (SECs) suitable for culturing or for obtaining cell lysates. In this protocol, the portal vein is used as the site for catheterization, rather than the vena cava, as this limits contamination of other possible cell types in the final liver preparation. No special instrumentation is required throughout the procedure. A water bath is used as a source of heat to maintain the temperature of all the buffers and solutions. A standard peristaltic pump is used to drive the fluid, and a refrigerated …

A Tlr/Akt/Foxo3 Immune Tolerance–Like Pathway Disrupts The Repair Capacity Of Oligodendrocyte Progenitors, Taasin Srivastava, Parham Diba, Justin M. Dean, Fatima Banine, Daniel Shaver, Matthew Hagen, Xi Gong, Weiping Su, Ben Emery, Daniel L. Marks, Edward N. Harris, Bruce Baggentoss, Paul H. Weigel, Larry S. Sherman, Stephen A. Back

Department of Biochemistry: Faculty Publications

Cerebral white matter injury (WMI) persistently disrupts myelin regeneration by oligodendrocyte progenitor cells (OPCs). We identified a specific bioactive hyaluronan fragment (bHAf) that downregulates myelin gene expression and chronically blocks OPC maturation and myelination via a tolerance-like mechanism that dysregulates pro-myelination signaling via AKT. Desensitization of AKT occurs via TLR4 but not TLR2 or CD44. OPC differentiation was selectively blocked by bHAf in a maturation-dependent fashion at the late OPC (preOL) stage by a noncanonical TLR4/TRIF pathway that induced persistent activation of the FoxO3 transcription factor downstream of AKT. Activated FoxO3 selectively localized to oligodendrocyte lineage cells in white matter …

3-O Sulfation Of Heparin Leads To Hepatotropism And Longer Circulatory Half-Life, Colton M. Miller, Yongmei Xu, Katrina M. Kudrna, Blake E. Hass, Brianna M. Kellar, Andrew W. Egger, Jian Liu, Edward N. Harris

Department of Biochemistry: Faculty Publications

Introduction: Heparins are common blood anticoagulants that are critical for many surgical and biomedical procedures used in modern medicine. In contrast to natural heparin derived from porcine gut mucosa, synthetic heparins are homogenous by mass, polymer length, and chemistry.

Materials & methods: Stable cell lines expressing the human and mouse Stabilin receptors were used to evaluate endocytosis of natural and synthetic heparin. We chemoenzymatically produced synthetic heparin consisting of 12 sugars (dodecamers) containing 14 sulfate groups resulting in a non-3-O sulfated structure (n12mer). Half of the n12mer was modified with a 3-O sulfate on a single GlcNS sugar producing the …

Characterization Of A Recurrent Missense Mutation In The Forkhead Dna-Binding Domain Of Foxp1, Tyler B. Johnson, Keegan Mechels, Ruth Ellen Anderson, Jacob T. Cain, David A. Sturdevant, Stephen Braddock, Hailey Pinz, Mark A. Wilson, Megan Landsverk, Kyle J. Roux, Jill M. Weimer

Department of Biochemistry: Faculty Publications

Haploinsufficiency of Forkhead box protein P1 (FOXP1), a highly conserved transcription factor, leads to developmental delay, intellectual disability, autism spectrum disorder, speech delay, and dysmorphic features. Most of the reported FOXP1 mutations occur on the C-terminus of the protein and cluster around to the forkhead domain. All reported FOXP1 pathogenic variants result in abnormal cellular localization and loss of transcriptional repression activity of the protein product. Here we present three patients with the same FOXP1 mutation, c.1574G>A (p.R525Q), that results in the characteristic loss of transcription repression activity. This mutation, however, represents the first reported FOXP1 mutation that does …

Editorial: Structure And Function Of Chloroplasts, Rebecca L. Roston, Juliette Jouhet, Fei Yu, Hongbo Gao

Department of Biochemistry: Faculty Publications

The primary energy resource of life on earth is the sun, whose energy is captured in the form of usable carbons by a process called photosynthesis. Photosynthesis occurs within a cellular organelle adapted to that purpose, called the chloroplast. Chloroplasts are unique metabolic and sensory organelles restricted to plants, algae, and a few protists. In this special topic, we aimed to gather new research, hypotheses, and reviews that would help us to better understand the important role of chloroplasts in all photosynthetic organisms. We were fortunate enough to have submissions from many talented chloroplast researchers. This topic contains a total …

Identification Of Genes Encoding Enzymes Catalyzing The Early Steps Of Carrot Polyacetylene Biosynthesis, Lucas Busta, Won Cheol Yim, Evan William Labrant, Peng Wang, Lindsey Grimes, Kiah Malyszka, John C. Cushman, Patricia Santos, Dylan K. Kosma, Edgar B. Cahoon

Department of Biochemistry: Faculty Publications

Polyacetylenic lipids accumulate in various Apiaceae species after pathogen attack, suggesting that these compounds are naturally occurring pesticides and potentially valuable resources for crop improvement. These compounds also promote human health and slow tumor growth. Even though polyacetylenic lipids were discovered decades ago, the biosynthetic pathway underlying their production is largely unknown. To begin filling this gap and ultimately enable polyacetylene engineering, we studied polyacetylenes and their biosynthesis in the major Apiaceae crop carrot (Daucus carota subsp. sativus). Using gas chromatography and mass spectrometry, we identified three known polyacetylenes and assigned provisional structures to two novel polyacetylenes. We …

Role Of Selenof As A Gatekeeper Of Secreted Disulfide-Rich Glycoproteins, Sun Hee Yim, Robert A. Everley, Frank A. Schildberg, Sang-Goo Lee, Andrea Orsi, Zachary R. Barbati, Kutay Karatepe, Dmitry E. Fomenko, Petra A. Tsuji, Hongbo R. Luo, Steven P. Gygi, Roberto Sitia, Arlene H. Sharpe, Dolph L. Hatfield, Vadim N. Gladyshev

Department of Biochemistry: Faculty Publications

Selenof (15-kDa selenoprotein; Sep15) is an endoplasmic reticulum (ER)-resident thioredoxin-like oxidoreductase that occurs in a complex with UDPglucose: glycoprotein glucosyltransferase. We found that Selenof deficiency in mice leads to elevated levels of non-functional circulating plasma immunoglobulins and increased secretion of IgM during in vitro splenic B cell differentiation. However, Selenof knockout animals show neither enhanced bacterial killing capacity nor antigen-induced systemic IgM activity, suggesting that excess immunoglobulins are not functional. In addition, ER-to-Golgi transport of a target glycoprotein was delayed in Selenof knockout embryonic fibroblasts, and proteomic analyses revealed that Selenof deficiency is primarily associated with antigen presentation and ER-to-Golgi …

Visualizing The Invisible: A Guide To Designing, Printing, And Incorporating Dynamic 3d Molecular Models To Teach Structure–Function Relationships, Michelle E. Howell, Karin V. Van Dijk, Christine S. Booth, Tomáš Helikar, Brian A. Couch, Rebecca Roston

Department of Biochemistry: Faculty Publications

Understanding the intricate relationship between macromolecular structure and function represents a central goal of undergraduate biology education (1–3). In teaching complex three-dimensional (3D) concepts, instructors typically depend on static two-dimensional (2D) textbook images or computer-based visualization software, which can lead to unintended misconceptions (4–6). While chemical and molecular kits exist, these models cannot handle the size and detail of macromolecules. Consequently, students may graduate in the life sciences without understanding how structure underlies function or acquiring skills to translate between 2D and 3D molecular models (5, 7).

Structural Basis For The Substrate Inhibition Of Proline Utilization A By Proline, David A. Korasick, Travis A. Pemberton, Benjamin W. Arentson, Donald F. Becker, John J. Tanner

Department of Biochemistry: Faculty Publications

Proline utilization A (PutA) is a bifunctional flavoenzyme that catalyzes the two-step oxidation of L-proline to L-glutamate using spatially separated proline dehydrogenase (PRODH) and L-glutamate-y-semialdehyde dehydrogenase (GSALDH) active sites. Substrate inhibition of the coupled PRODH-GSALDH reaction by proline is a common kinetic feature of PutAs, yet the structural basis for this phenomenon remains unknown. To understand the mechanism of substrate inhibition, we determined the 2.15 Å resolution crystal structure of Bradyrhizobium japonicum PutA complexed with proline. Proline was discovered in five locations remote from the PRODH active site. Most notably, strong electron density indicated that proline bound tightly to the …

Lncrna Meg3 Protects Endothelial Function By Regulating The Dna Damage Response, Mohamed Sham Shihabudeen Haider Ali, Xiao Cheng, Matthew Moran, Stefan Haemmig, Michael J. Naldrett, Sophie Alvarez, Mark W. Feinberg, Xinghui Sun

Department of Biochemistry: Faculty Publications

The role of long non-coding RNAs (lncRNAs) in regulating endothelial function through the DNA damage response (DDR) remains poorly understood. In this study, we demonstrate that lncRNA maternally expressed gene 3 (Meg3) interacts with the RNA binding protein polypyrimidine tract binding protein 3 (PTBP3) to regulate gene expression and endothelial function through p53 signaling a major coordinator of apoptosis and cell proliferation triggered by the DDR. Meg3 expression is induced in endothelial cells (ECs) upon p53 activation. Meg3 silencing induces DNA damage, activates p53 signaling, increases the expression of p53 target genes, promotes EC apoptosis, and inhibits EC proliferation. Mechanistically, …

Long-Chain Omega-3 Polyunsaturated Fatty Acids Modulate Mammary Gland Composition And Inflammation, Saraswoti Khadge, Geoffrey M. Thiele, J. Graham Sharp, Timothy R. Mcguire, Lynell W. Klassen, Paul N. Black, Concetta Dirusso, James Talmadge

Department of Biochemistry: Faculty Publications

Studies in rodents have shown that dietary modifications as mammary glands (MG) develop, regulates susceptibility to mammary tumor initiation. However, the effects of dietary PUFA composition on MGs in adult life, remains poorly understood. This study investigated morphological alterations and inflammatory microenvironments in the MGs of adult mice fed isocaloric and isolipidic liquid diets with varying compositions of omega (ω)-6 and long-chain (Lc)-ω3FA that were pair-fed. Despite similar consumption levels of the diets, mice fed the ω-3 diet had significantly lower body-weight gains, and abdominal-fat and mammary fat pad (MFP) weights. Fatty acid analysis showed significantly higher levels of Lc-ω-3FAs …

Dietary Omega-3 And Omega-6 Polyunsaturated Fatty Acids Modulate Hepatic Pathology, Saraswoti Khadge, J. Graham Sharp, Geoffrey M. Thiele, Timothy R. Mcguire, Lynell W. Klassen, Michael J. Duryee, Holly C. Britton, Jordan Beck, Paul N. Black, Concetta Dirusso, James Talmadge

Department of Biochemistry: Faculty Publications

Recent evidence has suggested that dietary polyunsaturated fatty acids (PUFAs) modulate inflammation; however, few studies have focused on the pathobiology of PUFA using isocaloric and isolipidic diets and it is unclear if the associated pathologies are due to dietary PUFA composition, lipid metabolism or obesity, as most studies compare diets fed ad libitum. Our studies used isocaloric and isolipidic liquid diets (35% of calories from fat), with differing compositions of omega (ω)-6 or long chain (Lc) ω-3 PUFA that were pair-fed and assessed hepatic pathology, inflammation and lipid metabolism. Consistent with an isocaloric, pair-fed model we observed no significant difference …

Adenosine Has Two Faces: Regionally Dichotomous Adenosine Tone In A Model Of Epilepsy With Comorbid Sleep Disorders, Ted J. Warren, Timothy A. Simeone, D. David Smith, Ryan Grove, Jiri Adamec, Kaeli K. Samson, Harrison M. Roundtree, Deepak Madhavan, Kristina A. Simeone

Department of Biochemistry: Faculty Publications

Objective: Adenosine participates in maintaining the excitatory/inhibitory balance in neuronal circuits. Studies indicate that adenosine levels in the cortex and hippocampus increase and exert sleep pressure in sleep-deprived and control animals, whereas in epilepsy reduced adenosine tone promotes hyperexcitability. To date, the role of adenosine in pathological conditions that result in both seizures and sleep disorders is unknown. Here, we determined adenosine tone in sleep and seizure regulating brain regions of Kv1.1 knockout (KO) mice, a model of temporal epilepsy with comorbid sleep disorders.

Methods: 1) Reverse phase-high performance liquid chromatography (RP-HPLC) was performed on brain tissue to determine levels …

A Behavioral Mechanistic Investigation Of The Role Of 5-Ht1a Receptors In The Mediation Of Rat Maternal Behavior, Xiaonan Li, Xiaojing Ding, Ruiyong Wu, Leilei Chen, Jun Gao, Gang Hu, Ming Li

Department of Psychology: Faculty Publications

Previous work suggests that 5-HT_1A receptors play a special role in rodent maternal aggression, but not in other aspects of maternal care (e.g. pup retrieval and nest building). The present study re-assessed the basic effects of 5-HT_1A activation or blockade on various maternal responses in postpartum female rats. We also examined the possible behavioral mechanisms underlying the maternal effects of 5-HT_1A. Sprague–Dawley mother rats were injected with a 5-HT_1A agonist 8-OH-DPAT (0.1, 0.5 or 1.0 mg/kg, sc), a 5-HT_1A antagonist WAY-101405 (0.1, 0.5 or 1.0 mg/kg, sc) or 0.9% saline solution on postpartum days …

Microstructural Changes To Proso Millet Protein Bodies Upon Cooking And Digestion, Paridhi Gulati, You Zhou, Christian Elowsky, Devin J. Rose

Department of Food Science and Technology: Faculty Publications

Cooking results in a drastic decline in digestibility of proso millet proteins, panicins. Scanning electron and confocal microscopy were used to observe morphological changes in proso millet protein bodies upon cooking and digestion that could be associated with the loss in digestibility. Spherical protein bodies (1–2.5 mm) were observed in proso millet flour and extracted protein. Cooking did not result in any noticeable change in the size or shape of the protein bodies. However, upon digestion with pepsin the poor digestibility of cooked proso millet protein was clearly evident from the differences in microstructure of the protein bodies: large cavities …

The Pul37 Tegument Protein Guides Alphaherpesvirus Retrograde Axonal Transport To Promote Neuroinvasion, Alexsia L. Richards, Patricia J. Sollars, Jared D. Pitts, Austin M. Stults, Ekaterina E. Heldwein, Gary E. Pickard, Gregory A. Smith

School of Veterinary and Biomedical Sciences: Faculty Publications

A hallmark property of the neurotropic alpha-herpesvirinae is the dissemination of infection to sensory and autonomic ganglia of the peripheral nervous system following an initial exposure at mucosal surfaces. The peripheral ganglia serve as the latent virus reservoir and the source of recurrent infections such as cold sores (herpes simplex virus type I) and shingles (varicella zoster virus). However, the means by which these viruses routinely invade the nervous system is not fully understood. We report that an internal virion component, the pUL37 tegument protein, has a surface region that is an essential neuroinvasion effector. Mutation of this region rendered …

Zika Virus Encoding Nonglycosylated Envelope Protein Is Attenuated And Defective In Neuroinvasion, Arun S. Annamalai, Aryamav Pattnaik, Bikash R. Sahoo, Ezhumalai Muthukrishnan, Sathish Kumar Natarajan, David Steffen, Hiep Vu, Gustavo Delho, Fernando Osorio, Thomas M. Petro, Shi-Hua Xiang, Asit K. Pattnaik

School of Veterinary and Biomedical Sciences: Faculty Publications

Zika virus (ZIKV), a mosquito-transmitted flavivirus responsible for sporadic outbreaks of mild and febrile illness in Africa and Asia, reemerged in the last decade causing serious human diseases, including microcephaly, congenital malformations, and Guillain-Barré syndrome. Although genomic and phylogenetic analyses suggest that genetic evolution may have led to the enhanced virulence of ZIKV, experimental evidence supporting the role of specific genetic changes in virulence is currently lacking. One sequence motif, VNDT, containing an N-linked glycosylation site in the envelope (E) protein, is polymorphic; it is absent in many of the African isolates but present in all isolates from the recent …

Zika Virus Encoding Nonglycosylated Envelope Protein Is Attenuated And Defective In Neuroinvasion, Arun Saravanakumar Annamalai, Aryamav Pattnaik, Bikash R. Sahoo, Ezhumalai Muthukrishnan, Sathish Kumar Natarajan, David Steffen, Hiep Vu, Gustavo A. Delhon, Fernando Osorio, Thomas M. Petro, Shi-Hua Xiang, Asit K. Pattnaik

School of Veterinary and Biomedical Sciences: Faculty Publications

ABSTRACT Zika virus (ZIKV), a mosquito-transmitted flavivirus responsible for sporadic outbreaks of mild and febrile illness in Africa and Asia, reemerged in the last decade causing serious human diseases, including microcephaly, congenital malformations, and Guillain-Barré syndrome. Although genomic and phylogenetic analyses suggest that genetic evolution may have led to the enhanced virulence of ZIKV, experimental evidence supporting the role of specific genetic changes in virulence is currently lacking. One sequence motif, VNDT, containing an N-linked glycosylation site in the envelope (E) protein, is polymorphic; it is absent in many of the African isolates but present in all isolates from the …

Mitochondrial Reactive Oxygen Species In Lipotoxic Hearts Induces Post-Translational Modifications Of Akap121, Drp1 And Opa1 That Promote Mitochondrial Fission, Kensuke Tsushima, Heiko Bugger, Adam R. Wende, Jamie Soto, Gregory A. Jenson, Austin R. Tor, Rose Mcglauflin, Helena C. Kenny, Yuan Zhang, Rhonda Souvenir, Xiao X. Hu, Crystal L. Sloan, Renata O. Pereira, Vitor A. Lira, Kenneth W. Spitzer, Terry L. Sharp, Kooresh I. Shoghi, Genevieve C. Sparagna, Eva A. Rog-Zielinska, Peter Kohl, Oleh Khalimonchuk, Jean E. Schaffer, E. Dale Abel

Department of Biochemistry: Faculty Publications

Rationale: Cardiac lipotoxicity, characterized by increased uptake, oxidation and accumulation of lipid intermediates, contributes to cardiac dysfunction in obesity and diabetes. However, mechanisms linking lipid overload and mitochondrial dysfunction are incompletely understood.

Objective: To elucidate the mechanisms for mitochondrial adaptations to lipid overload in postnatal hearts in vivo.

Methods and Results: Using a transgenic mouse model of cardiac lipotoxicity overexpressing long-chain acyl-CoA synthetase 1 in cardiomyocytes, we show that modestly increased myocardial fatty acid uptake leads to mitochondrial structural remodeling with significant reduction in minimum diameter. This is associated with increased palmitoyl-carnitine oxidation and increased reactive oxygen species (ROS) generation …

Effectiveness Of Composting As A Biosecure Disposal Method For Porcine Epidemic Diarrhea Virus (Pedv)-Infected Pig Carcasses, Sarah Vitosh-Sillman, John Dustin Loy, Bruce Brodersen, Clayton Kelling, Kent M. Eskridge, Amy Millmier Schmidt

School of Veterinary and Biomedical Sciences: Faculty Publications

Porcine epidemic diarrhea virus (PEDV) is an enteric disease of swine that has emerged as a worldwide threat to swine herd health and production. Substantial research has been conducted to assess viability of the virus on surfaces of vehicles and equipment, in feed and water, and on production building surfaces, but little is known about the persistence in PEDV-infected carcasses and effective disposal methods thereof. This study was conducted to quantify the persistence of PEDV RNA via quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR) at various time-temperature combinations and in infected piglet carcasses subjected to composting. Although this method …

Ydj1 Governs Fungal Morphogenesis And Stress Response, And Facilitates Mitochondrial Protein Import Via Mas1 And Mas2, Jinglin L. Xie, Iryna Bohovych, Erin O.Y. Wong, Jean-Philippe Lambert, Anne-Claude Gingras, Oleh Khalimonchuk, Leah E. Cowen, Michelle D. Leach

Department of Biochemistry: Faculty Publications

Mitochondria underpin metabolism, bioenergetics, signalling, development and cell death in eukaryotes. Most of the ~1,000 yeast mitochondrial proteins are encoded in the nucleus and synthesised as precursors in the cytosol, with mitochondrial import facilitated by molecular chaperones. Here, we focus on the Hsp40 chaperone Ydj1 in the fungal pathogen Candida albicans, finding that it is localised to both the cytosol and outer mitochondrial membrane, and is required for cellular stress responses and for filamentation, a key virulence trait. Mapping the Ydj1 protein interaction network highlighted connections with co-chaperones and regulators of filamentation. Furthermore, the mitochondrial processing peptidases Mas1 and …

Identification Of Potential Tissue-Specific Cancer Biomarkers And Development Of Cancer Versus Normal Genomic Classifiers, Akram Mohammed, Greyson Biegert, Jiri Adamec, Tomáš Helikar

Department of Biochemistry: Faculty Publications

Machine learning techniques for cancer prediction and biomarker discovery can hasten cancer detection and significantly improve prognosis. Recent “OMICS” studies which include a variety of cancer and normal tissue samples along with machine learning approaches have the potential to further accelerate such discovery. To demonstrate this potential, 2,175 gene expression samples from nine tissue types were obtained to identify gene sets whose expression is characteristic of each cancer class. Using random forests classification and ten-fold cross-validation, we developed nine single-tissue classifiers, two multi-tissue cancer-versus-normal classifiers, and one multi-tissue normal classifier. Given a sample of a specified tissue type, the single-tissue …

Organ-Specific Regulation Of Atp7a Abundance Is Coordinated With Systemic Copper Homeostasis, Haarin Chun, Tracy Catterson, Heejeong Kim, Jaekwon Lee, Byung-Eun Kim

Department of Biochemistry: Faculty Publications

Copper (Cu) is an essential cofactor for various enzymatic activities including mitochondrial electron transport, iron mobilization, and peptide hormone maturation. Consequently, Cu dysregulation is associated with fatal neonatal disease, liver and cardiac dysfunction, and anemia. While the Cu transporter ATP7A plays a major role in both intestinal Cu mobilization to the periphery and prevention of Cu over-accumulation, it is unclear how regulation of ATP7A contributes to Cu homeostasis in response to systemic Cu fluctuation. Here we show, using Cu-deficient mouse models, that steadystate levels of ATP7A are lower in peripheral tissues (including the heart, spleen, and liver) under Cu deficiency …