Life Sciences Commons^™

The Proteasomal Rpn11 Metalloprotease Suppresses Tombusvirus Rna Recombination And Promotes Viral Replication Via Facilitating Assembly Of The Viral Replicase Complex, K. Reddisiva Prasanth, Daniel Barajas, Peter D. Nagy

Plant Pathology Faculty Publications

RNA viruses co-opt a large number of cellular proteins that affect virus replication and, in some cases, viral genetic recombination. RNA recombination helps viruses in an evolutionary arms race with the host's antiviral responses and adaptation of viruses to new hosts. Tombusviruses and a yeast model host are used to identify cellular factors affecting RNA virus replication and RNA recombination. In this study, we have examined the role of the conserved Rpn11p metalloprotease subunit of the proteasome, which couples deubiquitination and degradation of proteasome substrates, in tombusvirus replication and recombination in Saccharomyces cerevisiae and plants. Depletion or mutations of Rpn11p …

Cell Type-Dependent Rna Recombination Frequency In The Japanese Encephalitis Virus, Wei-Wei Chiang, Chingkai Chuang, Mei Chao, Wei-June Chen

Plant Pathology Faculty Publications

Japanese encephalitis virus (JEV) is one of approximately 70 flaviviruses, frequently causing symptoms involving the central nervous system. Mutations of its genomic RNA frequently occur during viral replication, which is believed to be a force contributing to viral evolution. Nevertheless, accumulating evidences show that some JEV strains may have actually arisen from RNA recombination between genetically different populations of the virus. We have demonstrated that RNA recombination in JEV occurs unequally in different cell types. In the present study, viral RNA fragments transfected into as well as viral RNAs synthesized in mosquito cells were shown not to be stable, especially …

Construction Of A Sonchus Yellow Net Virus Minireplicon: A Step Toward Reverse Genetic Analysis Of Plant Negative-Strand Rna Viruses, Uma Ganesan, Jennifer N. Bragg, Min Deng, Sharon Marr, Mi Yeon Lee, Shasha Qian, Manling Shi, Justin Kappel, Cole Peters, Yeon Lee, Michael M. Goodin, Ralf G. Dietzgen, Zhenghe Li, Andrew O. Jackson

Plant Pathology Faculty Publications

Reverse genetic analyses of negative-strand RNA (NSR) viruses have provided enormous advances in our understanding of animal viruses over the past 20 years, but technical difficulties have hampered application to plant NSR viruses. To develop a reverse genetic approach for analysis of plant NSR viruses, we have engineered Sonchus yellow net nucleorhabdovirus (SYNV) minireplicon (MR) reporter cassettes for Agrobacterium tumefaciens expression in Nicotiana benthamiana leaves. Fluorescent reporter genes substituted for the SYNV N and P protein open reading frames (ORFs) exhibited intense single-cell foci throughout regions of infiltrated leaves expressing the SYNV MR derivatives and the SYNV nucleocapsid (N), phosphoprotein …

Plant-Symbiotic Fungi As Chemical Engineers: Multi-Genome Analysis Of The Clavicipitaceae Reveals Dynamics Of Alkaloid Loci, Christopher L. Schardl, Carolyn A. Young, Uljana Hesse, Stefan G. Amyotte, Kalina Andreeva, Patrick J. Calie, Damien J. Fleetwood, David C. Haws, Neil Moore, Birgitt Oeser, Daniel G. Panaccione, Kathryn K. Schweri, Christine R. Voisey, Mark L. Farman, Jerzy W. Jaromczyk, Bruce A. Roe, Donal M. O'Sullivan, Barry Scott, Paul Tudzynski, Zhiqiang An, Elissaveta G. Arnaoudova, Charles T. Bullock, Nikki D. Charlton, Li Chen, Murray Cox, Randy D. Dinkins, Simona Florea, Anthony E. Glenn, Anna Gordon, Ulrich Güldener, Daniel R. Harris, Walter Hollin, Jolanta Jaromczyk, Richard D. Johnson, Anar K. Khan, Eckhard Leistner, Adrian Leuchtmann, Chunjie Li, Jinge Liu, Jinze Liu, Miao Liu, Wade Mace, Caroline Machado, Padmaja Nagabhyru, Juan Pan, Jan Schmid, Koya Sugawara, Ulrike Steiner, Johanna E. Takach, Eiji Tanaka, Jennifer S. Webb, Ella V. Wilson, Jennifer L. Wiseman, Ruriko Yoshida, Zheng Zeng

Plant Pathology Faculty Publications

The fungal family Clavicipitaceae includes plant symbionts and parasites that produce several psychoactive and bioprotective alkaloids. The family includes grass symbionts in the epichloae clade (Epichloë and Neotyphodium species), which are extraordinarily diverse both in their host interactions and in their alkaloid profiles. Epichloae produce alkaloids of four distinct classes, all of which deter insects, and some-including the infamous ergot alkaloids-have potent effects on mammals. The exceptional chemotypic diversity of the epichloae may relate to their broad range of host interactions, whereby some are pathogenic and contagious, others are mutualistic and vertically transmitted (seed-borne), and still others vary in pathogenic …

Mites In The Promoters Of Effector Genes Allow Prediction Of Novel Virulence Genes In Fusarium Oxysporum, Sarah M. Schmidt, Petra M. Houterman, Ines Schreiver, Lisong Ma, Stefan G. Amyotte, Biju Chellappan, Sjef Boeren, Frank L. W. Takken, Martijn Rep

Plant Pathology Faculty Publications

BACKGROUND: The plant-pathogenic fungus Fusarium oxysporum f.sp.lycopersici (Fol) has accessory, lineage-specific (LS) chromosomes that can be transferred horizontally between strains. A single LS chromosome in the Fol4287 reference strain harbors all known Fol effector genes. Transfer of this pathogenicity chromosome confers virulence to a previously non-pathogenic recipient strain. We hypothesize that expression and evolution of effector genes is influenced by their genomic context.

RESULTS: To gain a better understanding of the genomic context of the effector genes, we manually curated the annotated genes on the pathogenicity chromosome and identified and classified transposable elements. Both retro- and DNA transposons are present …

Widespread Horizontal Gene Transfer From Circular Single-Stranded Dna Viruses To Eukaryotic Genomes, Huiquan Liu, Yanping Fu, Bo Li, Xiao Yu, Jiatao Xie, Jiasen Cheng, Said A. Ghabrial, Guoqing Li, Xianhong Yi, Daohong Jiang

Plant Pathology Faculty Publications

BACKGROUND: In addition to vertical transmission, organisms can also acquire genes from other distantly related species or from their extra-chromosomal elements (plasmids and viruses) via horizontal gene transfer (HGT). It has been suggested that phages represent substantial forces in prokaryotic evolution. In eukaryotes, retroviruses, which can integrate into host genome as an obligate step in their replication strategy, comprise approximately 8% of the human genome. Unlike retroviruses, few members of other virus families are known to transfer genes to host genomes.

RESULTS: Here we performed a systematic search for sequences related to circular single-stranded DNA (ssDNA) viruses in publicly available …

The Combined Effect Of Environmental And Host Factors On The Emergence Of Viral Rna Recombinants, Hannah M. Jaag, Peter D. Nagy

Plant Pathology Faculty Publications

Viruses are masters of evolution due to high frequency mutations and genetic recombination. In spite of the significance of viral RNA recombination that promotes the emergence of drug-resistant virus strains, the role of host and environmental factors in RNA recombination is poorly understood. Here we report that the host Met22p/Hal2p bisphosphate-3'-nucleotidase regulates the frequency of viral RNA recombination and the efficiency of viral replication. Based on Tomato bushy stunt virus (TBSV) and yeast as a model host, we demonstrate that deletion of MET22 in yeast or knockdown of AHL, SAL1 and FRY1 nucleotidases/phosphatases in plants leads to increased TBSV recombination …

Inhibition Of Rna Recruitment And Replication Of An Rna Virus By Acridine Derivatives With Known Anti-Prion Activities, Zsuzsanna Sasvari, Stéphane Bach, Marc Blondel, Peter D. Nagy

Plant Pathology Faculty Publications

BACKGROUND: Small molecule inhibitors of RNA virus replication are potent antiviral drugs and useful to dissect selected steps in the replication process. To identify antiviral compounds against Tomato bushy stunt virus (TBSV), a model positive stranded RNA virus, we tested acridine derivatives, such as chlorpromazine (CPZ) and quinacrine (QC), which are active against prion-based diseases.

METHODOLOGY/PRINCIPAL FINDINGS: Here, we report that CPZ and QC compounds inhibited TBSV RNA accumulation in plants and in protoplasts. In vitro assays revealed that the inhibitory effects of these compounds were manifested at different steps of TBSV replication. QC was shown to have an effect …

A Discontinuous Rna Platform Mediates Rna Virus Replication: Building An Integrated Model For Rna-Based Regulation Of Viral Processes, Baodong Wu, Judit Pogany, Hong Na, Beth L. Nicholson, Peter D. Nagy, K. Andrew White

Plant Pathology Faculty Publications

Plus-strand RNA viruses contain RNA elements within their genomes that mediate a variety of fundamental viral processes. The traditional view of these elements is that of local RNA structures. This perspective, however, is changing due to increasing discoveries of functional viral RNA elements that are formed by long-range RNA-RNA interactions, often spanning thousands of nucleotides. The plus-strand RNA genomes of tombusviruses exemplify this concept by possessing different long-range RNA-RNA interactions that regulate both viral translation and transcription. Here we report that a third fundamental tombusvirus process, viral genome replication, requires a long-range RNA-based interaction spanning approximately 3000 nts. In vivo …

'Paclims': A Component Lim System For High-Throughput Functional Genomic Analysis, Nicole Donofrio, Ravi Rajagopalon, Douglas Brown, Stephen Diener, Donald Windham, Shelly Nolin, Anna Floyd, Thomas Mitchell, Natalia Galadima, Sara Tucker, Marc J. Orbach, Gayatri Patel, Mark Farman, Vishal Pampanwar, Cari Soderlund, Yong-Hwan Lee, Ralph A. Dean

Plant Pathology Faculty Publications

BACKGROUND: Recent advances in sequencing techniques leading to cost reduction have resulted in the generation of a growing number of sequenced eukaryotic genomes. Computational tools greatly assist in defining open reading frames and assigning tentative annotations. However, gene functions cannot be asserted without biological support through, among other things, mutational analysis. In taking a genome-wide approach to functionally annotate an entire organism, in this application the approximately 11,000 predicted genes in the rice blast fungus (Magnaporthe grisea), an effective platform for tracking and storing both the biological materials created and the data produced across several participating institutions was required.

RESULTS: …