Digital Commons Network^™

Evidence For The Involvement Of Sphingosine-1-Phosphate In The Homing And Engraftment Of Hematopoietic Stem Cells To Bone Marrow, Mateusz Adamiak, Sylwia Borkowska, Marcin Wysoczynski, Malwina Suszynska, Magda Kucia, Gregg Rokosh, Ahmed Abdel-Latif, Janina Ratajczak, Mariusz Z. Ratajczak

Internal Medicine Faculty Publications

The α-chemokine stromal-derived factor 1 (SDF-1), which binds to the CXCR4 receptor, directs migration and homing of CXCR4⁺ hematopoietic stem/progenitor cells (HSPCs) to bone marrow (BM) stem cell niches. Nevertheless, it is also known that CXCR4^-/- fetal liver-derived hematopoietic stem cells engraft into BM and that blockade of CXCR4 by its antagonist AMD3100 does not prevent engraftment of HSPCs. Because of this finding of SDF-1-CXCR4-independent BM homing, the unique role of SDF-1 in HSPC homing has recently been challenged. While SDF-1 is the only chemokine that chemoattracts HSPCs, other chemoattractants for these cells have recently been described, including …

Increased Expression Of Fatty Acid Synthase Provides A Survival Advantage To Colorectal Cancer Cells Via Upregulation Of Cellular Respiration, Yekaterina Y. Zaytseva, Jennifer W. Harris, Mihail I. Mitov, Ji Tae Kim, D. Allan Butterfield, Eun Young Lee, Heidi L. Weiss, Tianyan Gao, B. Mark Evers

Markey Cancer Center Faculty Publications

Fatty acid synthase (FASN), a lipogenic enzyme, is upregulated in colorectal cancer (CRC). Increased de novo lipid synthesis is thought to be a metabolic adaptation of cancer cells that promotes survival and metastasis; however, the mechanisms for this phenomenon are not fully understood. We show that FASN plays a role in regulation of energy homeostasis by enhancing cellular respiration in CRC. We demonstrate that endogenously synthesized lipids fuel fatty acid oxidation, particularly during metabolic stress, and maintain energy homeostasis. Increased FASN expression is associated with a decrease in activation of energy-sensing pathways and accumulation of lipid droplets in CRC cells …

Calmodulin Methyltransferase Is Required For Growth, Muscle Strength, Somatosensory Development And Brain Function, Sitvanit Haziza, Roberta Magnani, Dima Lan, Omer Keinan, Ann Saada, Eli Hershkovitz, Nurit Yanay, Yoram Cohen, Yoram Nevo, Robert L. Houtz, Val C. Sheffield, Hava Golan, Ruti Parvari

Horticulture Faculty Publications

Calmodulin lysine methyl transferase (CaM KMT) is ubiquitously expressed and highly conserved from plants to vertebrates. CaM is frequently trimethylated at Lys-115, however, the role of CaM methylation in vertebrates has not been studied. CaM KMT was found to be homozygously deleted in the 2P21 deletion syndrome that includes 4 genes. These patients present with cystinuria, severe intellectual disabilities, hypotonia, mitochondrial disease and facial dysmorphism. Two siblings with deletion of three of the genes included in the 2P21 deletion syndrome presented with cystinuria, hypotonia, a mild/moderate mental retardation and a respiratory chain complex IV deficiency. To be able to attribute …

A Transcriptomal Analysis Of Bovine Oviductal Epithelial Cells Collected During The Follicular Phase Versus The Luteal Phase Of The Estrous Cycle, K. L. Cerny, E. Garrett, A. J. Walton, L. H. Anderson, P. J. Bridges

Animal and Food Sciences Faculty Publications

BACKGROUND: Reproductive success depends on a functional oviduct for gamete storage, maturation, fertilization, and early embryonic development. The ovarian-derived steroids estrogen and progesterone are key regulators of oviductal function. The objective of this study was to investigate luteal and follicular phase-specific oviductal epithelial cell function by using microarray-based transcriptional profiling, to increase our understanding of mRNAs regulating epithelial cell processes, and to identify novel genes and biochemical pathways that may be found to affect fertility in the future.

METHODS: Six normally cycling Angus heifers were assigned to either luteal phase (LP, n = 3) or follicular phase (FP, …

Stable Reference Gene Selection For Rt-Qpcr Analysis In Nonviruliferous And Viruliferous Frankliniella Occidentalis, Chunxiao Yang, Hui Li, Huipeng Pan, Yabin Ma, Deyong Zhang, Yong Liu, Zhanhong Zhang, Changying Zheng, Dong Chu

Entomology Faculty Publications

Reverse transcriptase-quantitative polymerase chain reaction (RT-qPCR) is a reliable technique for measuring and evaluating gene expression during variable biological processes. To facilitate gene expression studies, normalization of genes of interest relative to stable reference genes is crucial. The western flower thrips Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae), the main vector of tomato spotted wilt virus (TSWV), is a destructive invasive species. In this study, the expression profiles of 11 candidate reference genes from nonviruliferous and viruliferous F. occidentalis were investigated. Five distinct algorithms, geNorm, NormFinder, BestKeeper, the ΔCt method, and RefFinder, were used to determine the performance …

A Case Study Of The Impediments To The Commercialization Of Research At The University Of Kentucky, Nathan L. Vanderford, Elizabeth Marcinkowski

Markey Cancer Center Faculty Publications

The commercialization of university-based research occurs to varying degrees between academic institutions. Previous studies have found that multiple barriers can impede the effectiveness and efficiency by which academic research is commercialized. This case study was designed to better understand the impediments to research commercialization at the University of Kentucky via a survey and interview with three successful academic entrepreneurs. The study also garnered insight from the individuals as to how the commercialization process could be improved. Issues with commercialization infrastructure; a lack of emphasis, at the university level, on the importance of research commercialization; a void in an entrepreneurial culture …

Truncating Mutation In The Autophagy Gene Uvrag Confers Oncogenic Properties And Chemosensitivity In Colorectal Cancers, Shanshan He, Zhen Zhao, Yongfei Yang, Douglas O'Connell, Xiaowei Zhang, Soohwan Oh, Binyun Ma, Joo-Hyung Lee, Tian Zhang, Bino Varghese, Janae Yip, Sara Dolatshahi Pirooz, Ming Li, Yong Zhang, Guo-Min Li, Sue Ellen Martin, Keigo Machida, Chengyu Liang

Toxicology and Cancer Biology Faculty Publications

Autophagy-related factors are implicated in metabolic adaptation and cancer metastasis. However, the role of autophagy factors in cancer progression and their effect in treatment response remain largely elusive. Recent studies have shown that UVRAG, a key autophagic tumour suppressor, is mutated in common human cancers. Here we demonstrate that the cancer-related UVRAG frameshift (FS), which does not result in a null mutation, is expressed as a truncated UVRAG^FS in colorectal cancer (CRC) with microsatellite instability (MSI), and promotes tumorigenesis. UVRAG^FS abrogates the normal functions of UVRAG, including autophagy, in a dominant-negative manner. Furthermore, expression of UVRAG^FS can …

Beyond Bivariate Correlations: Three-Block Partial Least Squares Illustrated With Vegetation, Soil, And Topography, Daehyun Kim, Thomas J. Dewitt, Cesar S. B. Costa, John A. Kupfer, Ryan W. Mcewan, J. Anthony Stallins

Geography Faculty Publications

Ecologists, particularly those engaged in biogeomorphic studies, often seek to connect data from three or more domains. Using three-block partial least squares regression, we present a procedure to quantify and define bi-variance and tri-variance of data blocks related to plant communities, their soil parameters, and topography. Bi-variance indicates the total amount of covariation between these three domains taken in pairs, whereas tri-variance refers to the common variance shared by all domains. We characterized relationships among three domains (plant communities, soil properties, topography) for a salt marsh, four coastal dunes, and two temperate forests spanning several regions in the world. We …

Infusion Of Reconstituted High-Density Lipoprotein, Csl112, In Patients With Atherosclerosis: Safety And Pharmacokinetic Results From A Phase 2a Randomized Clinical Trial, Pierluigi Tricoci, Denise M. D'Andrea, Paul A. Gurbel, Zhenling Yao, Marina Cuchel, Brion Winston, Robert Schott, Robert Weiss, Michael A. Blazing, Louis Cannon, Alison L. Bailey, Dominick J. Angiolillo, Andreas Gille, Charles L. Shear, Samuel D. Wright, John H. Alexander

Gill Heart & Vascular Institute Faculty Publications

Background CSL112 is a new formulation of human apolipoprotein A‐I (apoA‐I) being developed to reduce cardiovascular events following acute coronary syndrome. This phase 2a, randomized, double‐blind, multicenter, dose‐ranging trial represents the first clinical investigation to assess the safety and pharmacokinetics/pharmacodynamics of a CSL112 infusion among patients with stable atherosclerotic disease.

Methods and Results Patients were randomized to single ascending doses of CSL112 (1.7, 3.4, or 6.8 g) or placebo, administered over a 2‐hour period. Primary safety assessments consisted of alanine aminotransferase or aspartate aminotransferase elevations >3× upper limits of normal and study drug–related adverse events. Pharmacokinetic/pharmacodynamic assessments included apoA‐I plasma …

The Sea Lamprey Meiotic Map Improves Resolution Of Ancient Vertebrate Genome Duplications, Jeramiah James Smith, Melissa C. Keinath

Biology Faculty Publications

It is generally accepted that many genes present in vertebrate genomes owe their origin to two whole-genome duplications that occurred deep in the ancestry of the vertebrate lineage. However, details regarding the timing and outcome of these duplications are not well resolved. We present high-density meiotic and comparative genomic maps for the sea lamprey (Petromyzon marinus), a representative of an ancient lineage that diverged from all other vertebrates ~550 million years ago. Linkage analyses yielded a total of 95 linkage groups, similar to the estimated number of germline chromosomes (1n ~ 99), spanning a total of 5570.25 cM. …

Characterization Of A Novel Megabirnavirus From Sclerotinia Sclerotiorum Reveals Horizontal Gene Transfer From Single-Stranded Rna Virus To Double-Stranded Rna Virus, Minghong Wang, Yong Wang, Xiangzhong Sun, Jiasen Cheng, Yanping Fu, Huiquan Liu, Daohong Jiang, Said A. Ghabrial, Jiatao Xie

Plant Pathology Faculty Publications

Mycoviruses have been detected in all major groups of filamentous fungi, and their study represents an important branch of virology. Here, we characterized a novel double-stranded RNA (dsRNA) mycovirus, Sclerotinia sclerotiorum megabirnavirus 1 (SsMBV1), in an apparently hypovirulent strain (SX466) of Sclerotinia sclerotiorum. Two similarly sized dsRNA segments (L1- and L2-dsRNA), the genome of SsMBV1, are packaged in rigid spherical particles purified from strain SX466. The full-length cDNA sequence of L1-dsRNA/SsMBV1 comprises two large open reading frames (ORF1 and ORF2), which encode a putative coat protein and an RNA-dependent RNA polymerase (RdRp), respectively. Phylogenetic analysis of the RdRp domain …

Noncontact Diffuse Correlation Tomography Of Human Breast Tumor, Lian He, Yu Lin, Chong Huang, Daniel Irwin, Margaret M. Szabunio, Guoqiang Yu

Biomedical Engineering Faculty Publications

Our first step to adapt our recently developed noncontact diffuse correlation tomography (ncDCT) system for three-dimensional (3-D) imaging of blood flow distribution in human breast tumors is reported. A commercial 3-D camera was used to obtain breast surface geometry, which was then converted to a solid volume mesh. An ncDCT probe scanned over a region of interest on the mesh surface and the measured boundary data were combined with a finite element framework for 3-D image reconstruction of blood flow distribution. This technique was tested in computer simulations and in vivo human breasts with low-grade carcinoma. Results from computer simulations …

A Less-Biased Analysis Of Metalloproteins Reveals Novel Zinc Coordination Geometries, Sen Yao, Robert M. Flight, Eric C. Rouchka, Hunter N. B. Moseley

Molecular and Cellular Biochemistry Faculty Publications

Zinc metalloproteins are involved in many biological processes and play crucial biochemical roles across all domains of life. Local structure around the zinc ion, especially the coordination geometry (CG), is dictated by the protein sequence and is often directly related to the function of the protein. Current methodologies in characterizing zinc metalloproteins' CG consider only previously reported CG models based mainly on nonbiological chemical context. Exceptions to these canonical CG models are either misclassified or discarded as "outliers." Thus, we developed a less-biased method that directly handles potential exceptions without pre-assuming any CG model. Our study shows that numerous exceptions …

Pharmacodynamic Assays To Facilitate Preclinical And Clinical Development Of Pre-Mrna Splicing Modulatory Drug Candidates, Yihui Shi, Amanda S. Joyner, William Shadrick, Gustavo Palacios, Chandraiah Lagisetti, Philip M. Potter, Lidia C. Sambucetti, Stefan Stamm, Thomas R. Webb

Molecular and Cellular Biochemistry Faculty Publications

The spliceosome has recently emerged as a new target for cancer chemotherapy and novel antitumor spliceosome targeted agents are under development. Here, we describe two types of novel pharmacodynamic assays that facilitate drug discovery and development of this intriguing class of innovative therapeutics; the first assay is useful for preclinical optimization of small-molecule agents that target the SF3B1 spliceosomal protein in animals, the second assay is an ex vivo validated, gel-based assay for the measurement of drug exposure in human leukocytes. The first assay utilizes a highly specific bioluminescent splicing reporter, based on the skipping of exons 4-11 of a …

The Cestode Community In Northern Fur Seals (Callorhinus Ursinus) On St. Paul Island, Alaska, Tetiana A Kuzmina, Jesús S. Hernández-Orts, Eugene T. Lyons, Terry R Spraker, Vadym V. Kornyushyn, Roman Kuchta

Veterinary Science Faculty Publications

The diversity and ecology of cestodes from the northern fur seals, Callorhinus ursinus (NFS), were examined using newly collected material from 756 humanely harvested subadult males between 2011 and 2014. NFSs were collected from five different haul-outs on St. Paul Island, Alaska. A total of 14,660 tapeworms were collected with a prevalence of 98.5% and intensity up to 107 cestodes per host (mean intensity 19.7 ± 16.5 SD). Three species of tapeworms were found: Adenocephalus pacificus (Diphyllobothriidea) was the most prevalent (prevalence 97.4%), followed by Diplogonoporus tetrapterus (49.7%), and 5 immature specimens of Anophryocephalus cf. ochotensis (Tetrabothriidea) (0.5%). Most of …

Engineering Plant Biomass Lignin Content And Composition For Biofuels And Bioproducts, Cassie Marie Welker, Vimal Kumar Balasubramanian, Carloalberto Petti, Krishan Mohan Rai, Seth Debolt, Venugopal Mendu

Horticulture Faculty Publications

Lignin is an aromatic biopolymer involved in providing structural support to plant cell walls. Compared to the other cell wall polymers, i.e., cellulose and hemicelluloses, lignin has been considered a hindrance in cellulosic bioethanol production due to the complexity involved in its separation from other polymers of various biomass feedstocks. Nevertheless, lignin is a potential source of valuable aromatic chemical compounds and upgradable building blocks. Though the biosynthetic pathway of lignin has been elucidated in great detail, the random nature of the polymerization (free radical coupling) process poses challenges for its depolymerization into valuable bioproducts. The absence of specific …

Benthic Collector And Grazer Communities Are Threatened By Hemlock Woolly Adelgid-Induced Eastern Hemlock Loss, Joshua K. Adkins, Lynne K. Rieske

Entomology Faculty Publications

Eastern hemlock (Tsuga canadensis (L.) is a foundation species in eastern North America where it is under threat from the highly invasive, exotic hemlock woolly adelgid (Adelges tsugae). Eastern hemlock is especially important in riparian areas of Central and Southern Appalachia, so we compared the spatial and temporal composition of benthic collector-gatherers, collector-filterers, and grazers in headwater streams with hemlock-dominated riparian vegetation to those with deciduous tree-dominated riparian vegetation to evaluate the extent to which adelgid-induced hemlock loss could influence composition and abundance of these two functional feeding groups. We found differences in benthic invertebrate abundance and …

A Gis-Based Expert Systems Predictive Habitat Model For Threatened And Endangered Species: Case Study Using Kentucky Arrow Darter, Benjamin L. Blandford, Michael Shouse, John Ripy

Kentucky Transportation Center Research Report

This study presents a GIS-based predictive habitat suitability model for the Kentucky arrow darter (Etheostoma spilotum), a fish species of the upper Kentucky River basin that is a candidate for federal listing by the U.S. Fish and Wildlife Service. The model is based on previous work: the development of a similar predictive model for identifying the habitat of the blackside dace, a threatened minnow species of the upper Cumberland River basin in Southeastern Kentucky. The research describes a weighted, rules-based system which incorporates expert knowledge about habitat preferences for the arrow darter. For this model, five habitat factors …

Chemically Related 4,5-Linked Aminoglycoside Antibiotics Drive Subunit Rotation In Opposite Directions, Michael R. Wasserman, Arto Pulk, Zhou Zhou, Roger B. Altman, John C. Zinder, Keith D. Green, Sylvie Garneau-Tsodikova, Jamie H. Doudna Cate, Scott C. Blanchard

Pharmaceutical Sciences Faculty Publications

Dynamic remodelling of intersubunit bridge B2, a conserved RNA domain of the bacterial ribosome connecting helices 44 (h44) and 69 (H69) of the small and large subunit, respectively, impacts translation by controlling intersubunit rotation. Here we show that aminoglycosides chemically related to neomycin-paromomycin, ribostamycin and neamine-each bind to sites within h44 and H69 to perturb bridge B2 and affect subunit rotation. Neomycin and paromomycin, which only differ by their ring-I 6'-polar group, drive subunit rotation in opposite directions. This suggests that their distinct actions hinge on the 6'-substituent and the drug's net positive charge. By solving the crystal structure of …

Pp2a Inhibitors Arrest G2/M Transition Through Jnk/Sp1-Dependent Down-Regulation Of Cdk1 And Autophagy-Dependent Up-Regulation Of P21, Fei-Ran Gong, Meng-Yao Wu, Meng Shen, Qiaoming Zhi, Ze-Kuan Xu, Rong Wang, Wen-Jie Wang, Yang Zong, Zeng-Liang Li, Yadi Wu, Binhua P. Zhou, Kai Chen, Min Tao, Wei Li

Markey Cancer Center Faculty Publications

Protein phosphatase 2A (PP2A) plays an important role in the control of the cell cycle. We previously reported that the PP2A inhibitors, cantharidin and okadaic acid (OA), efficiently repressed the growth of cancer cells. In the present study, we found that PP2A inhibitors arrested the cell cycle at the G2 phase through a mechanism that was dependent on the JNK pathway. Microarrays further showed that PP2A inhibitors induced expression changes in multiple genes that participate in cell cycle transition. To verify whether these expression changes were executed in a PP2A-dependent manner, we targeted the PP2A catalytic subunit (PP2Ac) using siRNA …

Reversal Of Aging-Related Neuronal Ca2+ Dysregulation And Cognitive Impairment By Delivery Of A Transgene Encoding Fk506-Binding Protein 12.6/1b To The Hippocampus, John C. Gant, Kuey-Chu Chen, Inga Kadish, Eric M. Blalock, Olivier Thibault, Nada M. Porter, Philip W. Landfield

Pharmacology and Nutritional Sciences Faculty Publications

Brain Ca(2+) regulatory processes are altered during aging, disrupting neuronal, and cognitive functions. In hippocampal pyramidal neurons, the Ca(2+)-dependent slow afterhyperpolarization (sAHP) exhibits an increase with aging, which correlates with memory impairment. The increased sAHP results from elevated L-type Ca(2+) channel activity and ryanodine receptor (RyR)-mediated Ca(2+) release, but underlying molecular mechanisms are poorly understood. Previously, we found that expression of the gene encoding FK506-binding protein 12.6/1b (FKBP1b), a small immunophilin that stabilizes RyR-mediated Ca(2+) release in cardiomyocytes, declines in hippocampus of aged rats and Alzheimer's disease subjects. Additionally, knockdown/disruption of hippocampal FKBP1b in young rats augments neuronal Ca(2+) responses. …

Hybrid Nanocrystals For Treatment And Bioimaging Of Disease, Tonglei Li

Pharmaceutical Sciences Faculty Patents

Hybrid nanocrystals able to reach specific targets in the body for treatment and biological imaging are provided, as well as methods of making and administering same for treatment of disease conditions and for bioimaging and radiotherapy. The hybrid nanocrystals and methods can be used alone or in combination with other treatment and imaging modalities.

A Quantitative Perspective On Surface Marker Selection For The Isolation Of Functional Tumor Cells, Calvin F. Cahall, Jacob L. Lilly, Edward A. Hirschowitz, Brad J. Berron

Chemical and Materials Engineering Faculty Publications

Much effort has gone into developing fluid biopsies of patient peripheral blood for the monitoring of metastatic cancers. One common approach is to isolate and analyze tumor cells in the peripheral blood. Widespread clinical implementation of this approach has been hindered by the current choice of targeting epithelial markers known to be highly variable in primary tumor sites. Here, we review current antigen-based tumor cell isolation strategies and offer biological context for commonly studied cancer surface markers. Expression levels of the most common markers are quantitated for three breast cancer and two non-small cell lung cancer (NSCLC) lineage models. These …

Targeted Dna Damage At Individual Telomeres Disrupts Their Integrity And Triggers Cell Death, Luxi Sun, Rong Tan, Jianquan Xu, Justin Laface, Ying Gao, Yanchun Xiao, Myriam Attar, Carola Neumann, Guo-Min Li, Bing Su, Yang Liu, Satoshi Nakajima, Arthur S. Levine, Li Lan

Markey Cancer Center Faculty Publications

Cellular DNA is organized into chromosomes and capped by a unique nucleoprotein structure, the telomere. Both oxidative stress and telomere shortening/dysfunction cause aging-related degenerative pathologies and increase cancer risk. However, a direct connection between oxidative damage to telomeric DNA, comprising <1% of the genome, and telomere dysfunction has not been established. By fusing the KillerRed chromophore with the telomere repeat binding factor 1, TRF1, we developed a novel approach to generate localized damage to telomere DNA and to monitor the real time damage response at the single telomere level. We found that DNA damage at long telomeres in U2OS cells is not repaired efficiently compared to DNA damage in non-telomeric regions of the same length in heterochromatin. Telomeric DNA damage shortens the average length of telomeres and leads to cell senescence in HeLa cells and cell death in HeLa, U2OS and IMR90 cells, when DNA damage at non-telomeric regions is undetectable. Telomere-specific damage induces chromosomal aberrations, including chromatid telomere loss and telomere associations, distinct from the damage induced by ionizing irradiation. Taken together, our results demonstrate that oxidative damage induces telomere dysfunction and underline the importance of maintaining telomere integrity upon oxidative damage.

Smoking Duration, Respiratory Symptoms, And Copd In Adults Aged ≥45 Years With A Smoking History, Yong Liu, Roy A. Pleasants, Janet B. Croft, Anne G. Wheaton, Khosrow Heidari, Ann M. Malarcher, Jill A. Ohar, Monica Kraft, David M. Mannino, Charlie Strange

Preventive Medicine and Environmental Health Faculty Publications

BACKGROUND: The purpose of this study was to assess the relationship of smoking duration with respiratory symptoms and history of chronic obstructive pulmonary disease (COPD) in the South Carolina Behavioral Risk Factor Surveillance System survey in 2012.

METHODS: Data from 4,135 adults aged ≥45 years with a smoking history were analyzed using multivariable logistic regression that accounted for sex, age, race/ethnicity, education, and current smoking status, as well as the complex sampling design.

RESULTS:The distribution of smoking duration ranged from 19.2% (1-9 years) to 36.2% (≥30 years). Among 1,454 respondents who had smoked for ≥30 years, 58.3% were current …

The Mitochondrial Peptidase Pitrilysin Degrades Islet Amyloid Polypeptide In Beta-Cells, Hanjun Guan, K. Martin Chow, Eunsuk Song, Nirmal Verma, Florin Despa, Louis B. Hersh

Molecular and Cellular Biochemistry Faculty Publications

Amyloid formation and mitochondrial dysfunction are characteristics of type 2 diabetes. The major peptide constituent of the amyloid deposits in type 2 diabetes is islet amyloid polypeptide (IAPP). In this study, we found that pitrilysin, a zinc metallopeptidase of the inverzincin family, degrades monomeric, but not oligomeric, islet amyloid polypeptide in vitro. In insulinoma cells when pitrilysin expression was decreased to 5% of normal levels, there was a 60% increase in islet amyloid polypeptide-induced apoptosis. In contrast, overexpression of pitrilysin protects insulinoma cells from human islet amyloid polypeptide-induced apoptosis. Since pitrilysin is a mitochondrial protein, we used immunofluorescence staining …

An Extended Polyanion Activation Surface In Insulin Degrading Enzyme, Eun Suk Song, Mehmet Ozbil, Tingting Zhang, Michael Sheetz, David Lee, Danny Tran, Sheng Li, Rajeev Prabhakar, Louis B. Hersh, David W. Rodgers

Molecular and Cellular Biochemistry Faculty Publications

Insulin degrading enzyme (IDE) is believed to be the major enzyme that metabolizes insulin and has been implicated in the degradation of a number of other bioactive peptides, including amyloid beta peptide (Aβ), glucagon, amylin, and atrial natriuretic peptide. IDE is activated toward some substrates by both peptides and polyanions/anions, possibly representing an important control mechanism and a potential therapeutic target. A binding site for the polyanion ATP has previously been defined crystallographically, but mutagenesis studies suggest that other polyanion binding modes likely exist on the same extended surface that forms one wall of the substrate-binding chamber. Here we use …

Crystal Structure Of O-Methyltransferase Calo6 From The Calicheamicin Biosynthetic Pathway: A Case Of Challenging Structure Determination At Low Resolution, Oleg V. Tsodikov, Caixia Hou, Christopher T. Walsh, Sylvie Garneau-Tsodikova

Pharmaceutical Sciences Faculty Publications

BACKGROUND: Calicheamicins (CAL) are enedyine natural products with potent antibiotic and cytotoxic activity, used in anticancer therapy. The O-methyltransferase CalO6 is proposed to catalyze methylation of the hydroxyl moiety at the C2 position of the orsellinic acid group of CAL.

RESULTS: Crystals of CalO6 diffracted non-isotropically, with the usable data extending to 3.4 Å. While no single method of crystal structure determination yielded a structure of CalO6, we were able to determine its structure by using molecular replacement-guided single wavelength anomalous dispersion by using diffraction data from native crystals of CalO6 and a highly non-isomorphous mercury derivative. The structure …

Plant Species' Origin Predicts Dominance And Response To Nutrient Enrichment And Herbivores In Global Grasslands, Eric W. Seabloom, Elizabeth T. Borer, Yvonne M. Buckley, Elsa E. Cleland, Kendi F. Davies, Jennifer Firn, W. Stanley Harpole, Yann Hautier, Eric M. Lind, Andrew S. Macdougall, John L. Orrock, Suzanne M. Prober, Peter B. Adler, T. Michael Anderson, Jonathan D. Bakker, Lori A. Biederman, Dana M. Blumenthal, Cynthia S. Brown, Lars A. Brudvig, Marc Cadotte, Chengjin Chu, Kathryn L. Cottingham, Michael J. Crawley, Ellen I. Damschen, Carla M. Dantonio, Nicole M. Decrappeo, Guozhen Du, Philip A. Fay, Paul Frater, Daniel S. Gruner, Nicole Hagenah, Andy Hector, Helmut Hillebrand, Kirsten S. Hofmockel, Hope C. Humphries, Virginia L. Jin, Adam Kay, Kevin P. Kirkman, Julia A. Klein, Johannes M. H. Knops, Kimberly J. La Pierre, Laura Ladwig, John G. Lambrinos, Qi Li, Wei Li, Robin Marushia, Rebecca L. Mcculley, Brett A. Melbourne, Charles E. Mitchell, Joslin L. Moore, John Morgan, Brent Mortensen, Lydia R. O'Halloran, David A. Pyke, Anita C. Risch, Mahesh Sankaran, Martin Schuetz, Anna Simonsen, Melinda D. Smith, Carly J. Stevens, Lauren Sullivan, Elizabeth Wolkovich, Peter D. Wragg, Justin Wright, Louie Yang

Plant and Soil Sciences Faculty Publications

Exotic species dominate many communities; however the functional significance of species' biogeographic origin remains highly contentious. This debate is fuelled in part by the lack of globally replicated, systematic data assessing the relationship between species provenance, function and response to perturbations. We examined the abundance of native and exotic plant species at 64 grasslands in 13 countries, and at a subset of the sites we experimentally tested native and exotic species responses to two fundamental drivers of invasion, mineral nutrient supplies and vertebrate herbivory. Exotic species are six times more likely to dominate communities than native species. Furthermore, while experimental …

Zbtb20 Is A Sequence-Specific Transcriptional Repressor Of Alpha-Fetoprotein Gene, Hai Zhang, Dongmei Cao, Luting Zhou, Ye Zhang, Xiaoqin Guo, Hui Li, Yuxia Chen, Brett T. Spear, Jia-Wei Wu, Zhifang Xie, Weiping J Zhang

Microbiology, Immunology, and Molecular Genetics Faculty Publications

Alpha-fetoprotein (AFP) represents a classical model system to study developmental gene regulation in mammalian cells. We previously reported that liver ZBTB20 is developmentally regulated and plays a central role in AFP postnatal repression. Here we show that ZBTB20 is a sequence-specific transcriptional repressor of AFP. By ELISA-based DNA-protein binding assay and conventional gel shift assay, we successfully identified a ZBTB20-binding site at -104/-86 of mouse AFP gene, flanked by two HNF1 sites and two C/EBP sites in the proximal promoter. Importantly, mutation of the core sequence in this site fully abolished its binding to ZBTB20 in vitro, as well …