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Chloroviruses, James L. Van Etten, Irina V. Agarkova, David D. Dunigan Dec 2019

Chloroviruses, James L. Van Etten, Irina V. Agarkova, David D. Dunigan

Nebraska Center for Virology: Faculty Publications

Chloroviruses are large dsDNA, plaque-forming viruses that infect certain chlorella-like green algae; the algae are normally mutualistic endosymbionts of protists and metazoans and are often referred to as zoochlorellae. The viruses are ubiquitous in inland aqueous environments throughout the world and occasionally single types reach titers of thousands of plaque-forming units per ml of native water. The viruses are icosahedral in shape with a spike structure located at one of the vertices. They contain an internal membrane that is required for infectivity. The viral genomes are 290 to 370 kb in size, which encode up to 16 tRNAs and 330 …


Genome-Wide Variation In Potyviruses, Deepti Nigam, Katherine Latourrette, Pedro F.N. Souza, Hernan Garcia Ruiz Nov 2019

Genome-Wide Variation In Potyviruses, Deepti Nigam, Katherine Latourrette, Pedro F.N. Souza, Hernan Garcia Ruiz

Nebraska Center for Virology: Faculty Publications

Potyviruses (family Potyviridae, genus Potyvirus) are the result of an initial radiation event that occurred 6,600 years ago. The genus currently consists of 167 species that infect monocots or dicots, including domesticated and wild plants. Potyviruses are transmitted in a non-persistent way by more than 200 species of aphids. As indicated by their wide host range, worldwide distribution, and diversity of their vectors, potyviruses have an outstanding capacity to adapt to new hosts and environments. However, factors that confer adaptability are poorly understood. Viral RNA-dependent RNA polymerases introduce nucleotide substitutions that generate genetic diversity. We hypothesized that selection imposed by …


Macrophage-Associated Wound Healing Contributes To African Green Monkey Siv Pathogenesis Control, Fredrik Barrenas, Kevin Raehtz, Cuiling Xu, Lynn Law, Richard R. Green, Guido Silvestri, Steven E. Bosinger, Andrew Nishida, Qingsheng Li, Wuxun Lu, Jianshui Zhang, Matthew J. Thomas, Jean Chang, Elise Smith, Jeffrey M. Weiss, Reem A. Dawoud, George H. Richter, Anita Trichel, Dongzhu Ma, Xinxia Peng, Jan Komorowski, Cristian Apetrei, Ivona Pandrea, Michael Gale Jr. Nov 2019

Macrophage-Associated Wound Healing Contributes To African Green Monkey Siv Pathogenesis Control, Fredrik Barrenas, Kevin Raehtz, Cuiling Xu, Lynn Law, Richard R. Green, Guido Silvestri, Steven E. Bosinger, Andrew Nishida, Qingsheng Li, Wuxun Lu, Jianshui Zhang, Matthew J. Thomas, Jean Chang, Elise Smith, Jeffrey M. Weiss, Reem A. Dawoud, George H. Richter, Anita Trichel, Dongzhu Ma, Xinxia Peng, Jan Komorowski, Cristian Apetrei, Ivona Pandrea, Michael Gale Jr.

Nebraska Center for Virology: Faculty Publications

Natural hosts of simian immunodeficiency virus (SIV) avoid AIDS despite lifelong infection. Here, we examined how this outcome is achieved by comparing a natural SIV host, African green monkey (AGM) to an AIDS susceptible species, rhesus macaque (RM). To asses gene expression profiles from acutely SIV infected AGMs and RMs, we developed a systems biology approach termed Conserved Gene Signature Analysis (CGSA), which compared RNA sequencing data from rectal AGM and RM tissues to various other species. We found that AGMs rapidly activate, and then maintain, evolutionarily conserved regenerative wound healing mechanisms in mucosal tissue. The wound healing protein fibronectin …


Dose Effects Of Recombinant Adenovirus Immunization In Rodents, Eric A. Weaver Oct 2019

Dose Effects Of Recombinant Adenovirus Immunization In Rodents, Eric A. Weaver

Nebraska Center for Virology: Faculty Publications

Recombinant adenovirus type 5 (rAd) has been used as a vaccine platform against many infectious diseases and has been shown to be an effective vaccine vector. The dose of the vaccine varies significantly from study to study, making it very diffcult to compare immune responses and vaccine effcacy. This study determined the immune correlates induced by serial dilutions of rAd vaccines delivered intramuscularly (IM) and intranasally (IN) to mice and rats. When immunized IM, mice had substantially higher antibody responses at the higher vaccine doses, whereas, the IN immunized mice showed a lower response to the higher rAd vaccine doses. …


The Vaccinia Virus (Vacv) B1 And Cellular Vrk2 Kinases Promote Vacv Replication Factory Formation Through Phosphorylation-Dependent Inhibition Of Vacv B12, Amber B. Rico, Zhigang Wang, Annabel T. Olson, Alexandria C. Linville, Brianna L. Bullard, Eric A. Weaver, Clinton Jones, Matthew S. Wiebea Oct 2019

The Vaccinia Virus (Vacv) B1 And Cellular Vrk2 Kinases Promote Vacv Replication Factory Formation Through Phosphorylation-Dependent Inhibition Of Vacv B12, Amber B. Rico, Zhigang Wang, Annabel T. Olson, Alexandria C. Linville, Brianna L. Bullard, Eric A. Weaver, Clinton Jones, Matthew S. Wiebea

Nebraska Center for Virology: Faculty Publications

Comparative examination of viral and host protein homologs reveals novel mechanisms governing downstream signaling effectors of both cellular and viral origin. The vaccinia virus B1 protein kinase is involved in promoting multiple facets of the virus life cycle and is a homolog of three conserved cellular enzymes called vaccinia virus-related kinases (VRKs). Recent evidence indicates that B1 and VRK2 mediate a common pathway that is largely uncharacterized but appears independent of previous VRK substrates. Interestingly, separate studies described a novel role for B1 in inhibiting vaccinia virus protein B12, which otherwise impedes an early event in the viral lifecycle. Herein, …


Longitudinal Quantification Of Adenovirus Neutralizing Responses In Zambian Mother-Infant Pairs: Impact Of Hiv-1 Infection And Its Treatment, Sara R. Privatt, Brianna L. Bullard, Eric A. Weaver, Charles Wood, John T. West Aug 2019

Longitudinal Quantification Of Adenovirus Neutralizing Responses In Zambian Mother-Infant Pairs: Impact Of Hiv-1 Infection And Its Treatment, Sara R. Privatt, Brianna L. Bullard, Eric A. Weaver, Charles Wood, John T. West

Nebraska Center for Virology: Faculty Publications

Vaccination offers the most cost-effective approach to limiting the adverse impact of infectious and neoplastic diseases that reduce the quality of life in sub-Saharan Africa (SSA). However, it is unclear what vaccine vectors would be most readily implementable in the setting and at what age they should be applied for maximal efficacy. Adenoviruses (Ad) and Ad-based vectors have been demonstrated to induce effective humoral and cellular immune responses in animal models and in humans. However, because immunity associated with Ad infection is lifelong, there exists a debate as to whether pre-existing immunity might decrease the efficacy of Ad vectored vaccines. …


A Human Papillomavirus-Independent Cervical Cancer Animal Model Reveals Unconventional Mechanisms Of Cervical Carcinogenesis, Chunbo He, Xiangmin Lv, Cong Huang, Peter C. Angeletti, Guohua Hua, Jixin Dong, Jin Zhou, Zhengfeng Wang, Bowen Ma, Xingcheng Chen, Paul F. Lambert, Bo R. Rueda, John S. Davis, Cheng Wang Mar 2019

A Human Papillomavirus-Independent Cervical Cancer Animal Model Reveals Unconventional Mechanisms Of Cervical Carcinogenesis, Chunbo He, Xiangmin Lv, Cong Huang, Peter C. Angeletti, Guohua Hua, Jixin Dong, Jin Zhou, Zhengfeng Wang, Bowen Ma, Xingcheng Chen, Paul F. Lambert, Bo R. Rueda, John S. Davis, Cheng Wang

Nebraska Center for Virology: Faculty Publications

HPV infections are common in healthy women and only rarely cause cervical cancer, suggesting that individual genetic susceptibility may play a critical role in the establishment of persistent HPV infection and the development of cervical cancer. Here, we provide convincing in vitro and in vivo evidence showing that differential expression and activation of YAP1 oncogene determine individual susceptibility to HPV infection and cervical carcinogenesis. We found that hyperactivation of YAP1 in mouse cervical epithelium was sufficient to induce invasive cervical cancer. Cervical epithelial cell-specific HPV16 E6/E7 and YAP1 double-knockin mouse model demonstrated that high-risk HPV synergized with hyperactivated YAP1 to …


Yap1-Lats2 Feedback Loop Dictates Senescent Or Malignant Cell Fate To Maintain Tissue Homeostasis, Chunbo He, Xiangmin Lv, Cong Huang, Guohua Hua, Bowen Ma, Xingcheng Chen, Peter C. Angeletti, Jixin Dong, Jin Zhou, Zhengfeng Wang, Bo R. Rueda, John S. Davis, Cheng Wang Feb 2019

Yap1-Lats2 Feedback Loop Dictates Senescent Or Malignant Cell Fate To Maintain Tissue Homeostasis, Chunbo He, Xiangmin Lv, Cong Huang, Guohua Hua, Bowen Ma, Xingcheng Chen, Peter C. Angeletti, Jixin Dong, Jin Zhou, Zhengfeng Wang, Bo R. Rueda, John S. Davis, Cheng Wang

Nebraska Center for Virology: Faculty Publications

Dysfunction of the homeostasis-maintaining systems in specific cell types or tissues renders the organism susceptible to a range of diseases, including cancers. One of the emerging mechanisms for maintaining tissue homeostasis is cellular senescence. Here, we report that the Hippo pathway plays a critical role in controlling the fate of ovarian cells. Hyperactivation of Yes-associated protein 1 (YAP1), the major effector of the Hippo pathway, induces senescence in cultured primary human ovarian surface epithelial cells (hOSEs). Large tumor suppressor 2 (LATS2), the primary upstream negative regulator of YAP1, is elevated in both YAP1-induced and natural replicative-triggered senescence. Deletion of LATS2 …


A Single-Cycle Adenovirus Type 7 Vaccine For Prevention Of Acute Respiratory Disease, Brianna L. Bullard, Brigette N. Corder, Eric A. Weaver Jan 2019

A Single-Cycle Adenovirus Type 7 Vaccine For Prevention Of Acute Respiratory Disease, Brianna L. Bullard, Brigette N. Corder, Eric A. Weaver

Nebraska Center for Virology: Faculty Publications

Adenovirus type 7 (Ad7) infection is associated with acute respiratory disease (ARD), especially in military recruits living in close quarters. Recently, several outbreaks of Ad7 infections have occurred in civilian populations, with some cases leading to death. However, the current Ad7 vaccine is licensed for use only in military recruits because it utilizes an orally delivered wild type virus which is shed in the stool for 28 days after immunization. This poses a safety risk due to the possibility of virus spread to vulnerable populations. To address the need for a safer Ad7 vaccine for use in civilian populations, we …


A Double Humanized Blt-Mice Model Featuring A Stable Human-Like Gut Microbiome And Human Immune System, Lance Daharsh, Jianshui Zhang, Amanda E. Ramer-Tait, Qingsheng Li Jan 2019

A Double Humanized Blt-Mice Model Featuring A Stable Human-Like Gut Microbiome And Human Immune System, Lance Daharsh, Jianshui Zhang, Amanda E. Ramer-Tait, Qingsheng Li

Nebraska Center for Virology: Faculty Publications

Humanized mice (hu-mice) that feature a functional human immune system have fundamentally changed the study of human pathogens and disease. They can be used to model diseases that are otherwise difficult or impossible to study in humans or other animal models. The gut microbiome can have a profound impact on human health and disease. However, the murine gut microbiome is very different than the one found in humans. There is a need for improved pre-clinical hu-mice models that have an engrafted human gut microbiome. Therefore, we created double hu-mice that feature both a human immune system and stable human-like gut …


Design And Characterization Of A Consensus Hemagglutinin Vaccine Immunogen Against H3 Influenza A Viruses Of Swine, Haiyan Sun, Jung-Hyang Sur, Sarah Vitosh-Sillman, David J. Steffen, Hiep Vu Jan 2019

Design And Characterization Of A Consensus Hemagglutinin Vaccine Immunogen Against H3 Influenza A Viruses Of Swine, Haiyan Sun, Jung-Hyang Sur, Sarah Vitosh-Sillman, David J. Steffen, Hiep Vu

Nebraska Center for Virology: Faculty Publications

The substantial genetic diversity exhibited by influenza A viruses of swine (IAV-S) represents the main challenge for the development of a broadly protective vaccine against this important pathogen. The consensus vaccine immunogen has proven an effective vaccinology approach to overcome the extraordinary genetic diversity of RNA viruses. In this project, we sought to determine if a consensus IAV-S hemagglutinin (HA) immunogen would elicit broadly protective immunity in pigs. To address this question, a consensus HA gene (designated H3-CON.1) was generated from a set of 1,112 H3 sequences of IAV-S recorded in GenBank from 2011 to 2015. The consensus HA gene …


Persistent Viral Reservoirs In Lymphoid Tissues In Siv-Infected Rhesus Macaques Of Chinese-Origin On Suppressive Antiretroviral Therapy, Summer Siddiqui, Stefanie Perez, Yong Gao, Lara Doyle-Meyers, Brian T. Foley, Qingsheng Li, Binhua Ling Jan 2019

Persistent Viral Reservoirs In Lymphoid Tissues In Siv-Infected Rhesus Macaques Of Chinese-Origin On Suppressive Antiretroviral Therapy, Summer Siddiqui, Stefanie Perez, Yong Gao, Lara Doyle-Meyers, Brian T. Foley, Qingsheng Li, Binhua Ling

Nebraska Center for Virology: Faculty Publications

Understanding HIV latent reservoirs in tissues is essential for the development of new strategies targeting these sites for eradication. Here, we assessed the size of latent reservoirs and the source of residual viruses in multiple lymphoid tissues of SIV-infected and fully suppressed rhesus macaques of Chinese-origin (cRMs). Eight cRMs were infected with SIVmac251 and treated with tenofovir and emtricitabine daily for 24 weeks initiated 4 weeks post-infection. Four of the eight animals reached sustained full viral suppression with undetectable viremia. The levels of cell-associated SIV DNA varied in peripheral blood mononuclear cells (PBMCs) and multiple lymphoid tissues, but with higher …


A Poxvirus Pseudokinase Represses Viral Dna Replication Via A Pathway Antagonized By Its Paralog Kinase, Annabel T. Olson, Zhigang Wang, Amber B. Rico, Matthew S. Wiebe Jan 2019

A Poxvirus Pseudokinase Represses Viral Dna Replication Via A Pathway Antagonized By Its Paralog Kinase, Annabel T. Olson, Zhigang Wang, Amber B. Rico, Matthew S. Wiebe

Nebraska Center for Virology: Faculty Publications

Poxviruses employ sophisticated, but incompletely understood, signaling pathways that engage cellular defense mechanisms and simultaneously ensure viral factors are modulated properly. For example, the vaccinia B1 protein kinase plays a vital role in inactivating the cellular antiviral factor BAF, and likely orchestrates other pathways as well. In this study, we utilized experimental evolution of a B1 deletion virus to perform an unbiased search for suppressor mutations and identify novel pathways involving B1. After several passages of the ΔB1 virus we observed a robust increase in viral titer of the adapted virus. Interestingly, our characterization of the adapted viruses reveals that …


Relationship Between The Cervical Microbiome, Hiv Status, And Precancerous Lesions, Cameron Klein, Daniela Gonzalez, Kandali Samwel, Crispin Kahesa, Julius Mwaiselage, Nirosh Aluthge, Samodha Fernando, John T. West, Charles Wood, Peter C. Angeletti Jan 2019

Relationship Between The Cervical Microbiome, Hiv Status, And Precancerous Lesions, Cameron Klein, Daniela Gonzalez, Kandali Samwel, Crispin Kahesa, Julius Mwaiselage, Nirosh Aluthge, Samodha Fernando, John T. West, Charles Wood, Peter C. Angeletti

Nebraska Center for Virology: Faculty Publications

Nearly all cervical cancers are causally associated with human papillomavirus (HPV). The burden of HPV-associated dysplasias in sub-Saharan Africa is influenced by HIV. To investigate the role of the bacterial microbiome in cervical dysplasia, cytobrush samples were collected directly from cervical lesions of 144 Tanzanian women. The V4 hypervariable region of the 16S rRNA gene was amplified and deep sequenced. Alpha diversity metrics (Chao1, PD whole tree, and operational taxonomic unit [OTU] estimates) displayed significantly higher bacterial richness in HIV-positive patients (P = 0.01) than in HIV-negative patients. In HIV-positive patients, there was higher bacterial richness in patients with …


Near-Atomic Structure Of A Giant Virus, Qianglin Fang, Dongjie Zhu, Irina Agarkova, Jagat Adhikari, Thomas Klose, Yue Liu, Zhenguo Chen, Yingyuan Sun, Michael L. Gross, James L. Van Etten, Xinzheng Zhang, Michael G. Rossmann Jan 2019

Near-Atomic Structure Of A Giant Virus, Qianglin Fang, Dongjie Zhu, Irina Agarkova, Jagat Adhikari, Thomas Klose, Yue Liu, Zhenguo Chen, Yingyuan Sun, Michael L. Gross, James L. Van Etten, Xinzheng Zhang, Michael G. Rossmann

Nebraska Center for Virology: Faculty Publications

Although the nucleocytoplasmic large DNA viruses (NCLDVs) are one of the largest group of viruses that infect many eukaryotic hosts, the near-atomic resolution structures of these viruses have remained unknown. Here we describe a 3.5 Å resolution icosahedrally averaged capsid structure of Paramecium bursaria chlorella virus 1 (PBCV-1). This structure consists of 5040 copies of the major capsid protein, 60 copies of the penton protein and 1800 minor capsid proteins of which there are 13 different types. The minor capsid proteins form a hexagonal network below the outer capsid shell, stabilizing the capsid by binding neighboring capsomers together. The size …


The Vaccinia Virus (Vacv) B1 And Cellular Vrk2 Kinases Promote Vacv Replication Factory Formation Through Phosphorylation-Dependent Inhibition Of Vacv B12, Annabel T. Olson, Zhigang Wang, Annabel Olson, Alexandria C. Linville, Brianna L. Bullard, Eric A. Weaver, Clinton Jones, Matthew S. Wiebe Jan 2019

The Vaccinia Virus (Vacv) B1 And Cellular Vrk2 Kinases Promote Vacv Replication Factory Formation Through Phosphorylation-Dependent Inhibition Of Vacv B12, Annabel T. Olson, Zhigang Wang, Annabel Olson, Alexandria C. Linville, Brianna L. Bullard, Eric A. Weaver, Clinton Jones, Matthew S. Wiebe

Nebraska Center for Virology: Faculty Publications

Comparative examination of viral and host protein homologs reveals novel mechanisms governing downstream signaling effectors of both cellular and vi- ral origin. The vaccinia virus B1 protein kinase is involved in promoting multiple facets of the virus life cycle and is a homolog of three conserved cellular enzymes called vaccinia virus-related kinases (VRKs). Recent evidence indicates that B1 and VRK2 mediate a com- mon pathway that is largely uncharacterized but appears independent of previous VRK substrates. Interestingly, separate studies described a novel role for B1 in inhibiting vac- cinia virus protein B12, which otherwise impedes an early event in the …