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Full-Text Articles in Life Sciences

Comparison Between Listeria Sensu Stricto And Listeria Sensu Lato Strains Identifies Novel Determinants Involved In Infection, Jakob Schardt, Grant Jones, Stefanie Müller-Herbst, Kristina Schauer, Sarah E. F. D'Orazio, Thilo M. Fuchs Dec 2017

Comparison Between Listeria Sensu Stricto And Listeria Sensu Lato Strains Identifies Novel Determinants Involved In Infection, Jakob Schardt, Grant Jones, Stefanie Müller-Herbst, Kristina Schauer, Sarah E. F. D'Orazio, Thilo M. Fuchs

Microbiology, Immunology, and Molecular Genetics Faculty Publications

The human pathogen L. monocytogenes and the animal pathogen L. ivanovii, together with four other species isolated from symptom-free animals, form the "Listeria sensu stricto" clade. The members of the second clade, "Listeria sensu lato", are believed to be solely environmental bacteria without the ability to colonize mammalian hosts. To identify novel determinants that contribute to infection by L. monocytogenes, the causative agent of the foodborne disease listeriosis, we performed a genome comparison of the two clades and found 151 candidate genes that are conserved in the Listeria sensu stricto species. Two factors were …


Ablation Of An Ovarian Tumor Family Deubiquitinase Exposes The Underlying Regulation Governing The Plasticity Of Cell Cycle Progression In Toxoplasma Gondii, Animesh Dhara, Rodrigo De Paula Baptista, Jessica C. Kissinger, Ernest Charles Snow, Anthony P. Sinai Nov 2017

Ablation Of An Ovarian Tumor Family Deubiquitinase Exposes The Underlying Regulation Governing The Plasticity Of Cell Cycle Progression In Toxoplasma Gondii, Animesh Dhara, Rodrigo De Paula Baptista, Jessica C. Kissinger, Ernest Charles Snow, Anthony P. Sinai

Microbiology, Immunology, and Molecular Genetics Faculty Publications

The Toxoplasma genome encodes the capacity for distinct architectures underlying cell cycle progression in a life cycle stage-dependent manner. Replication in intermediate hosts occurs by endodyogeny, whereas a hybrid of schizogony and endopolygeny occurs in the gut of the definitive feline host. Here, we characterize the consequence of the loss of a cell cycle-regulated ovarian tumor (OTU family) deubiquitinase, OTUD3A of Toxoplasma gondii (TgOTUD3A; TGGT1_258780), in T. gondii tachyzoites. Rather than the mutation being detrimental, mutant parasites exhibited a fitness advantage, outcompeting the wild type. This phenotype was due to roughly one-third of TgOTUD3A-knockout (TgOTUD3A-KO) tachyzoites exhibiting deviations from endodyogeny …


The Soybean Rfg1 Gene Restricts Nodulation By Sinorhizobium Fredii Usda193, Yinglun Fan, Jinge Liu, Shanhua Lyu, Qi Wang, Shengming Yang, Hongyan Zhu Sep 2017

The Soybean Rfg1 Gene Restricts Nodulation By Sinorhizobium Fredii Usda193, Yinglun Fan, Jinge Liu, Shanhua Lyu, Qi Wang, Shengming Yang, Hongyan Zhu

Plant and Soil Sciences Faculty Publications

Sinorhizobium fredii is a fast-growing rhizobial species that can establish a nitrogen-fixing symbiosis with a wide range of legume species including soybeans (Glycine max). In soybeans, this interaction shows a high level of specificity such that particular S. fredii strains nodulate only a limited set of plant genotypes. Here we report the identification of a dominant gene in soybeans that restricts nodulation with S. fredii USDA193. Genetic mapping in an F2 population revealed co-segregation of the underlying locus with the previously cloned Rfg1 gene. The Rfg1 allele encodes a member of the Toll-interleukin receptor/nucleotide-binding site/leucine-rich repeat class of …


Pro-Angiogenesis Therapy And Aging: A Mini-Review, Charles T. Ambrose Aug 2017

Pro-Angiogenesis Therapy And Aging: A Mini-Review, Charles T. Ambrose

Microbiology, Immunology, and Molecular Genetics Faculty Publications

Apart from major illnesses and chronic afflictions, the elderly experience lesser ailments, such as muscle weakness, cold intolerance, and transient memory lapses. Physical signs in the aged include wrinkled skin and the slow healing of skin abrasions. These ailments and signs are grouped together because they may be due in part to an age-linked, waning microcirculation. A reduced capillary density (CD) throughout the body of aged people and animals has been reported in over 40 papers. The reduced CD is due in turn to declining levels of angiogenic growth factors (AGFs) throughout the body during old age, as documented in …


The Feoabc Locus Of Yersinia Pestis Likely Has Two Promoters Causing Unique Iron Regulation, Lauren O'Connor, Jacqueline D. Fetherston, Robert D. Perry Jul 2017

The Feoabc Locus Of Yersinia Pestis Likely Has Two Promoters Causing Unique Iron Regulation, Lauren O'Connor, Jacqueline D. Fetherston, Robert D. Perry

Microbiology, Immunology, and Molecular Genetics Faculty Publications

The FeoABC ferrous transporter is a wide-spread bacterial system. While the feoABC locus is regulated by a number of factors in the bacteria studied, we have previously found that regulation of feoABC in Yersinia pestis appears to be unique. None of the non-iron responsive transcriptional regulators that control expression of feoABC in other bacteria do so in Y. pestis. Another unique factor is the iron and Fur regulation of the Y. pestis feoABC locus occurs during microaerobic but not aerobic growth. Here we show that this unique iron-regulation is not due to a unique aspect of the Y. pestis …


Crystal Structure Of Yersinia Pestis Virulence Factor Yfea Reveals Two Polyspecific Metal-Binding Sites, Christopher D. Radka, Lawrence J. Delucas, Landon S. Wilson, Matthew B. Lawrenz, Robert D. Perry, Stephen G. Aller Jul 2017

Crystal Structure Of Yersinia Pestis Virulence Factor Yfea Reveals Two Polyspecific Metal-Binding Sites, Christopher D. Radka, Lawrence J. Delucas, Landon S. Wilson, Matthew B. Lawrenz, Robert D. Perry, Stephen G. Aller

Microbiology, Immunology, and Molecular Genetics Faculty Publications

Gram-negative bacteria use siderophores, outer membrane receptors, inner membrane transporters and substrate-binding proteins (SBPs) to transport transition metals through the periplasm. The SBPs share a similar protein fold that has undergone significant structural evolution to communicate with a variety of differentially regulated transporters in the cell. In Yersinia pestis, the causative agent of plague, YfeA (YPO2439, y1897), an SBP, is important for full virulence during mammalian infection. To better understand the role of YfeA in infection, crystal structures were determined under several environmental conditions with respect to transition-metal levels. Energy-dispersive X-ray spectroscopy and anomalous X-ray scattering data show that …


Zinc Transporters Ybtx And Znuabc Are Required For The Virulence Of Yersinia Pestis In Bubonic And Pneumonic Plague In Mice, Alexander G. Bobrov, Olga Kirillina, Marina Y. Fosso, Jacqueline D. Fetherston, M. Clarke Miller, Tiva T. Vancleave, Joseph A. Burlison, William K. Arnold, Matthew B. Lawrenz, Sylvie Garneau-Tsodikova, Robert D. Perry Jun 2017

Zinc Transporters Ybtx And Znuabc Are Required For The Virulence Of Yersinia Pestis In Bubonic And Pneumonic Plague In Mice, Alexander G. Bobrov, Olga Kirillina, Marina Y. Fosso, Jacqueline D. Fetherston, M. Clarke Miller, Tiva T. Vancleave, Joseph A. Burlison, William K. Arnold, Matthew B. Lawrenz, Sylvie Garneau-Tsodikova, Robert D. Perry

Microbiology, Immunology, and Molecular Genetics Faculty Publications

A number of bacterial pathogens require the ZnuABC Zinc (Zn2+) transporter and/or a second Zn2+ transport system to overcome Zn2+ sequestration by mammalian hosts. Previously we have shown that in addition to ZnuABC, Yersinia pestis possesses a second Zn2+ transporter that involves components of the yersiniabactin (Ybt), siderophore-dependent iron transport system. Synthesis of the Ybt siderophore and YbtX, a member of the major facilitator superfamily, are both critical components of the second Zn2+ transport system. Here we demonstrate that a ybtX znu double mutant is essentially avirulent in mouse models of bubonic and pneumonic …


Overcoming Hurdles To Development Of A Vaccine Against Pneumocystis Jirovecii, Beth A. Garvy Apr 2017

Overcoming Hurdles To Development Of A Vaccine Against Pneumocystis Jirovecii, Beth A. Garvy

Microbiology, Immunology, and Molecular Genetics Faculty Publications

Development of Pneumocystis pneumonia (PCP) is a common problem among immunosuppressed individuals. There are windows of opportunity in which vaccination would be beneficial, but to date, no vaccines have made it to clinical trials. Significant hurdles to vaccine development include host range specificity, making it difficult to translate from animal models to humans. Discovery of cross-reactive epitopes is critical to moving vaccine candidates from preclinical animal studies to clinical trials.


Pneumocystis Infection Alters The Activation State Of Pulmonary Macrophages, Jessica M. Deckman, Cathryn J. Kurkjian, Joseph P. Mcgillis, Theodore J. Cory, Susan E. Birket, Linda M. Schutzman, Brian S. Murphy, Beth A. Garvy, David J. Feola Feb 2017

Pneumocystis Infection Alters The Activation State Of Pulmonary Macrophages, Jessica M. Deckman, Cathryn J. Kurkjian, Joseph P. Mcgillis, Theodore J. Cory, Susan E. Birket, Linda M. Schutzman, Brian S. Murphy, Beth A. Garvy, David J. Feola

Microbiology, Immunology, and Molecular Genetics Faculty Publications

Recent studies show a substantial incidence of Pneumocystis jirovecii colonization and infection in patients with chronic inflammatory lung conditions. However, little is known about the impact of Pneumocystis upon the regulation of pulmonary immunity. We demonstrate here that Pneumocystis polarizes macrophages towards an alternatively activated macrophage-like phenotype. Genetically engineered mice that lack the ability to signal through IL-4 and IL-13 were used to show that Pneumocystis alternative macrophage activation is dependent upon signaling through these cytokines. To determine whether Pneumocystis-induced macrophage polarization would impact subsequent immune responses, we infected mice with Pneumocystis and then challenged them with Pseudomonas aeruginosa 14 …


Identification Of Mutant Genes And Introgressed Tiger Salamander Dna In The Laboratory Axolotl, Ambystoma Mexicanum, M. Ryan Woodcock, Jennifer Vaughn-Wolfe, Alexandra Elias, David Kevin Kump, Katharina Denise Kendall, Nataliya Y. Timoshevskaya, Vladimir A. Timoshevskiy, Dustin W. Perry, Jeramiah James Smith, Jessica E. Spiewak, David M. Parichy, Stephen Randal Voss Jan 2017

Identification Of Mutant Genes And Introgressed Tiger Salamander Dna In The Laboratory Axolotl, Ambystoma Mexicanum, M. Ryan Woodcock, Jennifer Vaughn-Wolfe, Alexandra Elias, David Kevin Kump, Katharina Denise Kendall, Nataliya Y. Timoshevskaya, Vladimir A. Timoshevskiy, Dustin W. Perry, Jeramiah James Smith, Jessica E. Spiewak, David M. Parichy, Stephen Randal Voss

Biology Faculty Publications

The molecular genetic toolkit of the Mexican axolotl, a classic model organism, has matured to the point where it is now possible to identify genes for mutant phenotypes. We used a positional cloning–candidate gene approach to identify molecular bases for two historic axolotl pigment phenotypes: white and albino. White (d/d) mutants have defects in pigment cell morphogenesis and differentiation, whereas albino (a/a) mutants lack melanin. We identified in white mutants a transcriptional defect in endothelin 3 (edn3), encoding a peptide factor that promotes pigment cell migration and differentiation in other …


Radiation Induced Apoptosis Of Murine Bone Marrow Cells Is Independent Of Early Growth Response 1 (Egr1), Karine Z. Oben, Beth W. Gachuki, Sara S. Alhakeem, Mary Kathryn Mckenna, Ying Liang, Daret K. St. Clair, Vivek M. Rangnekar, Subbarao Bondada Jan 2017

Radiation Induced Apoptosis Of Murine Bone Marrow Cells Is Independent Of Early Growth Response 1 (Egr1), Karine Z. Oben, Beth W. Gachuki, Sara S. Alhakeem, Mary Kathryn Mckenna, Ying Liang, Daret K. St. Clair, Vivek M. Rangnekar, Subbarao Bondada

Microbiology, Immunology, and Molecular Genetics Faculty Publications

An understanding of how each individual 5q chromosome critical deleted region (CDR) gene contributes to malignant transformation would foster the development of much needed targeted therapies for the treatment of therapy related myeloid neoplasms (t-MNs). Early Growth Response 1 (EGR1) is a key transcriptional regulator of myeloid differentiation located within the 5q chromosome CDR that has been shown to regulate HSC (hematopoietic stem cell) quiescence as well as the master regulator of apoptosis—p53. Since resistance to apoptosis is a hallmark of malignant transformation, we investigated the role of EGR1 in apoptosis of bone marrow cells; a cell population from which …


Characterization Of A Large Vertebrate Genome And Homomorphic Sex Chromosomes In The Axolotl, Ambystoma Mexicanum, Melissa Keinath Jan 2017

Characterization Of A Large Vertebrate Genome And Homomorphic Sex Chromosomes In The Axolotl, Ambystoma Mexicanum, Melissa Keinath

Theses and Dissertations--Biology

Changes in the structure, content and morphology of chromosomes accumulate over evolutionary time and contribute to cell, developmental and organismal biology. The axolotl (Ambystoma mexicanum) is an important model for studying these changes because: 1) it provides important phylogenetic perspective for reconstructing the evolution of vertebrate genomes and amphibian karyotypes, 2) its genome has evolved to a large size (~10X larger than human) but has maintained gene orders, and 3) it possesses potentially young sex chromosomes that have not undergone extensive differentiation in the structure that is typical of many other vertebrate sex chromosomes (e.g. mammalian XY chromosomes …


Mitochondrial And Nuclear Patterns Of Conflict And Concordance At The Gene, Genome, And Behavioral Scales In Desmognathus Salamanders, Justin D. Kratovil Jan 2017

Mitochondrial And Nuclear Patterns Of Conflict And Concordance At The Gene, Genome, And Behavioral Scales In Desmognathus Salamanders, Justin D. Kratovil

Theses and Dissertations--Biology

Advancements in molecular sequencing have revealed unexpected cryptic genetic diversity and contrasting evolutionary histories within genes and between genomes of many organisms; often in disagreement with recognized taxonomy. Incongruent patterns between the mitochondrial and nuclear evolutionary history can have several plausible explanations, but widespread systematic conflict inevitably challenges our conceptions of species boundaries when there is discordance between coevolving and coinherited genomes. It is unknown to what degree mitonuclear conflict drives the process of divergence, or how ubiquitous these patterns are across the tree of life. To understand the evolutionary relevance of intergenomic discordance we must identify the conflicting patterns …


Antisense Afp Transcripts In Mouse Liver And Their Potential Role In Afp Gene Regulation, Maria S. Dixon Jan 2017

Antisense Afp Transcripts In Mouse Liver And Their Potential Role In Afp Gene Regulation, Maria S. Dixon

Theses and Dissertations--Microbiology, Immunology, and Molecular Genetics

Hepatocellular carcinoma (HCC) is the most common form of primary liver cancer, ranking the sixth most common cancer and third most common cause of cancer mortality worldwide. Alpha-fetoprotein (AFP) is a plasma protein that is highly expressed in the fetal liver and shut off after birth. AFP expression is elevated in regenerating adult liver and HCC and has been used extensively as a diagnostic marker of liver cancer. We have been studying mouse liver gene regulation to better understand mechanisms by which changes in gene expression contribute to liver development, homeostasis and disease. Zinc Fingers and Homeoboxes 2 (Zhx2) has …


Transcriptomic Analyses Of Cathatranthus Roseus Hairy Roots Overexpressing Crmyc2 And Orca3 And Roles Of Cross-Family Transcription Factor Interaction In Terpenoid Indole Alkaloid Biosynthesis, Xueyi Sui Jan 2017

Transcriptomic Analyses Of Cathatranthus Roseus Hairy Roots Overexpressing Crmyc2 And Orca3 And Roles Of Cross-Family Transcription Factor Interaction In Terpenoid Indole Alkaloid Biosynthesis, Xueyi Sui

Theses and Dissertations--Plant and Soil Sciences

Catharanthus roseus (Madagascar periwinkle), is a well-known medicinal plant that produces a vast array of terpenoid indole alkaloids (TIAs), including two anticancer compounds vinblastine and vincristine. Industrial scale production of TIAs is hampered by the difficulties of total chemical synthesis of these compounds and the fragmented knowledge on TIA pathway. Transcriptional regulation of the TIA biosynthetic pathway has not been thoroughly investigated in Catharanthus and only a few structural genes have been identified as the targets of two master regulators: the basic helix-loop-helix (bHLH) transcription factor (TF) CrMYC2 and APETALA2/ETHYLENE RESPONSE FACTOR (AP2/ERF), ORCA3. Next generation sequencing (NGS) has been …