bluuebunny/crossref_metadata_2025_split huggingface dataset:
An Amino Acid of Human Parainfluenza Virus Type 3 Nucleoprotein Is Critical for Template Function and Cytoplasmic Inclusion Body Formation
Authors: Zhang Shengwei , Chen Longyun , Zhang Guangyuan , Yan Qin , Yang Xiaodan , Ding Binbin , Tang Qiaopeng , Sun Shengjun , Hu Zhulong , Chen Mingzhou 
Published: September 2013

ABSTRACT

The nucleoprotein (N) and phosphoprotein (P) interaction of nonsegmented negative-strand RNA viruses is essential for viral replication; this includes N
0
-P (N
0
, free of RNA) interaction and the interaction of N-RNA with P. The precise site(s) within N that mediates the N-P interaction and the detailed regulating mechanism, however, are less clear. Using a human parainfluenza virus type 3 (HPIV3) minigenome assay, we found that an N mutant (N
L478A
) did not support reporter gene expression. Using
in vivo
and
in vitro
coimmunoprecipitation, we found that N
L478A
maintains the ability to form N
L478A
0
-P, to self-assemble, and to form N
L478A
-RNA but that N
L478A
-RNA does not interact with P. Using an immunofluorescence assay, we found that N-P interaction provides the minimal requirement for the formation of cytoplasmic inclusion bodies, which contain viral RNA, N, P, and polymerase in HPIV3-infected cells. N
L478A
was unable to form inclusion bodies when coexpressed with P, but the presence of N rescued the ability of N
L478A
to form inclusion bodies and the transcriptional function of N
L478A
, thereby suggesting that hetero-oligomers formed by N and N
L478A
are functional and competent to form inclusion bodies. Furthermore, we found that N
L478A
is also defective in virus growth. To our knowledge, we are the first to use a paramyxovirus to identify a precise amino acid within N that is critical for N-RNA and P interaction but not for N
0
-P interaction for the formation of inclusion bodies, which appear to be bona fide sites of RNA synthesis.
The Structure and Host Entry of an Invertebrate Parvovirus
Authors: Meng Geng , Zhang Xinzheng , Plevka Pavel , Yu Qian , Tijssen Peter , Rossmann Michael G. 
Published: September 2013

ABSTRACT

The 3.5-Å resolution X-ray crystal structure of mature cricket parvovirus (
Acheta domesticus
densovirus [
Ad
DNV]) has been determined. Structural comparisons show that vertebrate and invertebrate parvoviruses have evolved independently, although there are common structural features among all parvovirus capsid proteins. It was shown that raising the temperature of the
Ad
DNV particles caused a loss of their genomes. The structure of these emptied particles was determined by cryo-electron microscopy to 5.5-Å resolution, and the capsid structure was found to be the same as that for the full, mature virus except for the absence of the three ordered nucleotides observed in the crystal structure. The viral protein 1 (VP1) amino termini could be externalized without significant damage to the capsid.
In vitro
, this externalization of the VP1 amino termini is accompanied by the release of the viral genome.
A Direct and Versatile Assay Measuring Membrane Penetration of Adenovirus in Single Cells
Authors: Suomalainen Maarit , Luisoni Stefania , Boucke Karin , Bianchi Sarah , Engel Daniel A. , Greber Urs F. 
Published: September 2013

ABSTRACT
Endocytosis is the most prevalent entry port for viruses into cells, but viruses must escape from the lumen of endosomes to ensure that viral genomes reach a site for replication and progeny formation. Endosomal escape also helps viruses bypass endolysosomal degradation and presentation to certain Toll-like intrinsic immunity receptors. The mechanisms for cytosolic delivery of nonenveloped viruses or nucleocapsids from enveloped viruses are poorly understood, in part because no quantitative assays are readily available which directly measure the penetration of viruses into the cytosol. Following uptake by clathrin-mediated endocytosis or macropinocytosis, the nonenveloped adenoviruses penetrate from endosomes to the cytosol, and they traffic with cellular motors on microtubules to the nucleus for replication. In this report, we present a novel single-cell imaging assay which quantitatively measures individual cytosolic viruses and distinguishes them from endosomal viruses or viruses at the plasma membrane. Using this assay, we showed that the penetration of human adenoviruses of the species C and B occurs rapidly after virus uptake. Efficient penetration does not require acidic pH in endosomes. This assay is versatile and can be adapted to other adenoviruses and members of other nonenveloped and enveloped virus families.
Middle East Respiratory Syndrome Coronavirus Accessory Protein 4a Is a Type I Interferon Antagonist
Authors: Niemeyer Daniela , Zillinger Thomas , Muth Doreen , Zielecki Florian , Horvath Gabor , Suliman Tasnim , Barchet Winfried , Weber Friedemann , Drosten Christian , Müller Marcel A. 
Published: September 2013

ABSTRACT
Middle East respiratory syndrome coronavirus (MERS-CoV) causes severe acute respiratory infection with as yet unclear epidemiology. We previously showed that MERS-CoV counteracts parts of the innate immune response in human bronchiolar cells. Here we analyzed accessory proteins 3, 4a, 4b, and 5 for their abilities to inhibit the type I interferon response. Accessory protein 4a was found to block interferon induction at the level of melanoma differentiation-associated protein 5 (MDA5) activation presumably by direct interaction with double-stranded RNA.
Structural Analysis of the Hemagglutinin from the Recent 2013 H7N9 Influenza Virus
Authors: Yang Hua , Carney Paul J. , Chang Jessie C. , Villanueva Julie M. , Stevens James 
Published: September 2013

ABSTRACT
In March 2013, the Chinese Center for Disease Control and Prevention reported human infections with an H7N9 influenza virus, and by 20 July 2013, the numbers of laboratory-confirmed cases had climbed to 134, including 43 fatalities and 127 hospitalizations. The newly emerging H7N9 viruses constitute an obvious public health concern because of the apparent severity of this outbreak. Here we focus on the hemagglutinins (HAs) of these viruses and assess their receptor binding phenotype in relation to previous HAs studied. Glycan microarray and kinetic analyses of recombinant A(H7N9) HAs were performed to compare the receptor binding profile of wild-type receptor binding site variants at position 217, a residue analogous to one of two positions known to switch avian to human receptor preference in H2N2 and H3N2 viruses. Two recombinant A(H7N9) HAs were structurally characterized, and a mutational study of the receptor binding site was performed to analyze important residues that can affect receptor preference and affinity. Results highlight a weak human receptor preference of the H7N9 HAs, suggesting that these viruses require further adaptation in order to adapt fully to humans.
Kaposi's Sarcoma-Associated Herpesvirus K7 Modulates Rubicon-Mediated Inhibition of Autophagosome Maturation
Authors: Liang Qiming , Chang Brian , Brulois Kevin F. , Castro Kamilah , Min Chan-Ki , Rodgers Mary A. , Shi Mude , Ge Jianning , Feng Pinghui , Oh Byung-Ha , Jung Jae U. 
Published: September 2013

ABSTRACT
Autophagy is an important innate safeguard mechanism for protecting an organism against invasion by pathogens. We have previously discovered that Kaposi's sarcoma-associated herpesvirus (KSHV) evades this host defense through tight suppression of autophagy by targeting multiple steps of autophagy signal transduction. Here, we report that KSHV K7 protein interacts with Rubicon autophagy protein and inhibits the autophagosome maturation step by blocking Vps34 enzymatic activity, further highlighting how KSHV deregulates autophagy-mediated host immunity for its life cycle.
Homologous Recombination in E3 Genes of Human Adenovirus Species D
Authors: Singh Gurdeep , Robinson Christopher M. , Dehghan Shoaleh , Jones Morris S. , Dyer David W. , Seto Donald , Chodosh James 
Published: September 2013

ABSTRACTGenes within the E3 transcription unit of human adenoviruses modulate host immune responses to infection. A comprehensive genomics and bioinformatics analysis of the E3 transcription unit for 38 viruses within human adenovirus species D (HAdV-D) revealed distinct and surprising patterns of homologous recombination. Homologous recombination was identified in open reading frames for E3 CR1α, CR1β, and CR1γ, similar to that previously observed with genes encoding the three major structural capsid proteins, the penton base, hexon, and fiber.
Structure, Adsorption to Host, and Infection Mechanism of Virulent Lactococcal Phage p2
Authors: Bebeacua Cecilia , Tremblay Denise , Farenc Carine , Chapot-Chartier Marie-Pierre , Sadovskaya Irina , van Heel Marin , Veesler David , Moineau Sylvain , Cambillau Christian 
Published: September 2013

ABSTRACT

Lactococcal siphophages from the 936 and P335 groups infect the Gram-positive bacterium
Lactococcus lactis
using receptor binding proteins (RBPs) attached to their baseplate, a large multiprotein complex at the distal part of the tail. We have previously reported the crystal and electron microscopy (EM) structures of the baseplates of phages p2 (936 group) and TP901-1 (P335 group) as well as the full EM structure of the TP901-1 virion. Here, we report the complete EM structure of siphophage p2, including its capsid, connector complex, tail, and baseplate. Furthermore, we show that the p2 tail is characterized by the presence of protruding decorations, which are related to adhesins and are likely contributed by the major tail protein C-terminal domains. This feature is reminiscent of the tail of
Escherichia coli
phage λ and
Bacillus subtilis
phage SPP1 and might point to a common mechanism for establishing initial interactions with their bacterial hosts. Comparative analyses showed that the architecture of the phage p2 baseplate differs largely from that of lactococcal phage TP901-1. We quantified the interaction of its RBP with the saccharidic receptor and determined that specificity is due to lower
k
off
values of the RBP/saccharidic dissociation. Taken together, these results suggest that the infection of
L. lactis
strains by phage p2 is a multistep process that involves reversible attachment, followed by baseplate activation, specific attachment of the RBPs to the saccharidic receptor, and DNA ejection.
A Single Amino Acid Mutation in the Envelope Cytoplasmic Tail Restores the Ability of an Attenuated Simian Immunodeficiency Virus Mutant To Deplete Mucosal CD4
+
T Cells
Authors: Breed Matthew W. , Jordan Andrea P. O. , Aye Pyone P. , Sugimoto Chie , Alvarez Xavier , Kuroda Marcelo J. , Pahar Bapi , Keele Brandon F. , Hoxie James A. , Lackner Andrew A. 
Published: September 2013

ABSTRACT

Disruption of the conserved motif GYxxØ in the simian immunodeficiency virus (SIV) SIVmac239 envelope (Env) cytoplasmic tail resulted in a virus (ΔGY) that exhibited a high plasma peak but uniquely failed to acutely deplete mucosal CD4
+
T cells. Here, we show that ΔGY containing a flanking S727P mutation that was acquired in ΔGY-infected macaques reacquired the ability to rapidly deplete CD4
+
T cells in lamina propria. This suggests that the GYxxØ motif and S727P each contribute to SIV's targeting to mucosal tissues.
Influenza A Virus Proteins NS1 and Hemagglutinin Along with M2 Are Involved in Stimulation of Autophagy in Infected Cells
Authors: Zhirnov O. P. , Klenk H. D. 
Published: September 2013

ABSTRACT
The NS1 protein of influenza A virus is known to downregulate apoptosis early in infection in order to support virus replication (O. P. Zhirnov, T. E. Konakova, T. Wolff, and H. D. Klenk, J. Virol. 76:1617–1625, 2002). In the present study, we analyzed the development of autophagy, another mechanism to protect cells from degradation that depends on NS1 expression. To this end, we compared autophagy in cells infected with wild-type (WT) influenza virus and virus lacking the NS1 gene (delNS1 virus). The results show that in WT-infected cells but not in delNS1 virus-infected cells, synthesis of the autophagy marker LC3-II, the lipidated form of microtubule light chain-associated protein LC3, is stimulated and that LC3-II accumulates in a perinuclear zone enriched with double-layered membrane vesicles characteristic of autophagosomes. Transfection experiments revealed that NS1 expressed alone was unable to upregulate autophagy, whereas hemagglutinin (HA) and M2 were. Proteolytic cleavage of HA increased autophagy. Taken together, these observations indicate that NS1 stimulates autophagy indirectly by upregulating the synthesis of HA and M2. Thus, it appears that NS1, besides downregulating apoptosis, is involved in upregulation of autophagy and that it supports the survival of infected cells by both mechanisms.
The Perils of Pathogen Discovery: Origin of a Novel Parvovirus-Like Hybrid Genome Traced to Nucleic Acid Extraction Spin Columns
Authors: Naccache Samia N. , Greninger Alexander L. , Lee Deanna , Coffey Lark L. , Phan Tung , Rein-Weston Annie , Aronsohn Andrew , Hackett John , Delwart Eric L. , Chiu Charles Y. 
Published: September 2013

ABSTRACT

Next-generation sequencing was used for discovery and
de novo
assembly of a novel, highly divergent DNA virus at the interface between the
Parvoviridae
and
Circoviridae
. The virus, provisionally named parvovirus-like hybrid virus (PHV), is nearly identical by sequence to another DNA virus, NIH-CQV, previously detected in Chinese patients with seronegative (non-A-E) hepatitis. Although we initially detected PHV in a wide range of clinical samples, with all strains sharing ∼99% nucleotide and amino acid identity with each other and with NIH-CQV, the exact origin of the virus was eventually traced to contaminated silica-binding spin columns used for nucleic acid extraction. Definitive confirmation of the origin of PHV, and presumably NIH-CQV, was obtained by in-depth analyses of water eluted through contaminated spin columns. Analysis of environmental metagenome libraries detected PHV sequences in coastal marine waters of North America, suggesting that a potential association between PHV and diatoms (algae) that generate the silica matrix used in the spin columns may have resulted in inadvertent viral contamination during manufacture. The confirmation of PHV/NIH-CQV as laboratory reagent contaminants and not bona fide infectious agents of humans underscores the rigorous approach needed to establish the validity of new viral genomes discovered by next-generation sequencing.
Epstein-Barr Virus Induces Global Changes in Cellular mRNA Isoform Usage That Are Important for the Maintenance of Latency
Authors: Homa Nicholas J. , Salinas Raul , Forte Eleonora , Robinson Timothy J. , Garcia-Blanco Mariano A. , Luftig Micah A. 
Published: September 2013

ABSTRACT

Oncogenic viruses promote cell proliferation through the dramatic reorganization of host transcriptomes. In addition to regulating mRNA abundance, changes in mRNA isoform usage can have a profound impact on the protein output of the transcriptome. Using Epstein-Barr virus (EBV) transformation of primary B cells, we have studied the ability of an oncogenic virus to alter the mRNA isoform profile of its host. Using the algorithm called SplicerEX with two complementary Affymetrix microarray platforms, we uncovered 433 mRNA isoform changes regulated by EBV during B-cell transformation. These changes were largely orthogonal with the 2,163 mRNA abundance changes observed during transformation, such that less than one-third of mRNAs changing at the level of isoform also changed in overall abundance. While we observed no preference for a mechanistic class of mRNA isoform change, we detected a significant shortening of 3′ untranslated regions and exclusion of cassette exons in EBV-transformed cells relative to uninfected B cells. Gene ontology analysis of the mRNA isoform changes revealed significant enrichment in nucleic acid binding proteins. We validated several of these isoform changes and were intrigued by those in two mRNAs encoding the proteins XBP1 and TCF4, which have both been shown to bind and activate the promoter of the major EBV lytic
trans
-activator BZLF1. Our studies indicate that EBV latent infection promotes the usage of mRNA isoforms of XBP1 and TCF4 that restrict BZLF1 activation. Therefore, characterization of global changes in mRNA isoform usage during EBV infection identifies a new mechanism for the maintenance of latent infection.
Emergency Care Handover (ECHO study) across care boundaries: the need for joint decision making and consideration of psychosocial history
Authors: Sujan Mark A , Chessum Peter , Rudd Michelle , Fitton Laurence , Inada-Kim Matthew , Spurgeon Peter , Cooke Matthew W 
Published: September 2013

BackgroundInadequate handover in emergency care is a threat to patient safety. Handover across care boundaries poses particular problems due to different professional, organisational and cultural backgrounds. While there have been many suggestions for standardisation of handover content, relatively little is known about the verbal behaviours that shape handover conversations. This paper explores both what is communicated (content) and how this is communicated (verbal behaviours) during different types of handover conversations across care boundaries in emergency care.MethodsThree types of interorganisational (ambulance service to emergency department (ED) in ‘resuscitation’ and ‘majors’ areas) and interdepartmental handover conversations (referrals to acute medicine) were audio recorded in three National Health Service EDs. Handover conversations were segmented into utterances. Frequency counts for content and language forms were derived for each type of handover using Discourse Analysis. Verbal behaviours were identified using Conversation Analysis.Results203 handover conversations were analysed. Handover conversations involving ambulance services were predominantly descriptive (60%–65% of utterances), unidirectional and focused on patient presentation (75%–80%). Referrals entailed more collaborative talk focused on the decision to admit and immediate care needs. Across all types of handover, only 1.5%–5% of handover conversation content related to the patient's social and psychological needs.ConclusionsHandover may entail both descriptive talk aimed at information transfer and collaborative talk aimed at joint decision-making. Standardisation of handover needs to accommodate collaborative aspects and should incorporate communication of information relevant to the patient's social and psychological needs to establish appropriate care arrangements at the earliest opportunity.
HER-2/neu Mediates Oncogenic Transformation via Altered CREB Expression and Function
Authors: Steven André , Leisz Sandra , Massa Chiara , Iezzi Manuela , Lattanzio Rossano , Lamolinara Alessia , Bukur Jürgen , Müller Anja , Hiebl Bernhard , Holzhausen Hans-Jürgen , Seliger Barbara 
Published: September 2013

Abstract
The cyclic (c)AMP responsive element binding protein (CREB) plays a key role in many cellular processes, including differentiation, proliferation, and signal transduction. Furthermore, CREB overexpression was found in tumors of distinct origin and evidence suggests an association with tumorigenicity. To establish a mechanistic link between HER-2/neu–mediated transformation and CREB protein expression and function, in vitro models of HER-2/neu–overexpressing and HER-2/neu–negative/silenced counterparts as well as human mammary carcinoma lesions with defined HER-2/neu status were used. HER-2/neu overexpression resulted in the induction and activation of CREB protein in vitro and in vivo, whereas short hairpin RNA (shRNA)–mediated inhibition of HER-2/neu correlated with downregulated CREB activity. CREB activation in HER-2/neu–transformed cells enhanced distinct signal transduction pathways, whereas their inhibition negatively interfered with CREB expression and/or activation. CREB downregulation in HER-2/neu–transformed cells by shRNA and by the inhibitors KG-501 and lapatinib caused morphologic changes, reduced cell proliferation with G0–G1 cell-cycle arrest, which was rescued by CREB expression. This was accompanied by reduced cell migration, wound healing, an increased fibronectin adherence, invasion, and matrix metalloproteinase expression. In vivo shCREB-HER-2/neu+ cells, but not control cells, exerted a significantly decreased tumorgenicity that was associated with decreased proliferative capacity, enhanced apoptosis, and increased frequency of T lymphocytes in peripheral blood mononuclear cells. Thus, CREB plays an important role in the HER-2/neu–mediated transformation by altering in vitro and in vivo growth characteristics.
Implications: These data suggest that CREB affects tumor immunogenicity and is a potential target for cancer therapy. Mol Cancer Res; 11(11); 1462–77. ©2013 AACR.
Deferasirox Induces Mesenchymal–Epithelial Transition in Crocidolite-Induced Mesothelial Carcinogenesis in Rats
Authors: Nagai Hirotaka , Okazaki Yasumasa , Chew Shan Hwu , Misawa Nobuaki , Yasui Hiroyuki , Toyokuni Shinya 
Published: September 2013

Abstract
Asbestos was used worldwide in huge quantities in the past century. However, because of the unexpected carcinogenicity to mesothelial cells with an extremely long incubation period, many countries face this long-lasting social problem. Mesothelioma is often diagnosed in an advanced stage, for which no effective therapeutic protocols are yet established. We previously reported on the basis of animal experiments that the major pathology in asbestos-induced mesothelial carcinogenesis is local iron overload. Here, we undertook to find an effective strategy to prevent, delay, or lower the malignant potential of mesothelioma during asbestos-induced carcinogenesis. We used intraperitoneal injections of crocidolite to rats. We carried out a 16-week study to seek the maximal-tolerated intervention for iron reduction via oral deferasirox administration or intensive phlebotomy. Splenic iron deposition was significantly decreased with either method, and we found that Perls' iron staining in spleen is a good indicator for iron reduction. We injected a total of 10 mg crocidolite at the age of six weeks, and the preventive measures were via repeated oral administration of 25 to 50 mg/kg/d deferasirox or weekly to bimonthly phlebotomy of 4 to 10 mL/kg/d. The animals were observed until 110 weeks. Deferasirox administration significantly increased the fraction of less malignant epithelioid subtype. Although we found a slightly prolonged survival in deferasirox-treated female rats, larger sample size and refinement of the current protocol are necessary to deduce the cancer-preventive effects of deferasirox. Still, our results suggest deferasirox serves as a potential preventive strategy in people already exposed to asbestos via iron reduction. Cancer Prev Res; 6(11); 1222–30. ©2013 AACR.