Search results for "Capsid Protein"
showing 10 items of 137 documents
G2 rotavirus infections in an infantile population of the South of Italy: variability of viral strains over time.
2005
Rotavirus positive samples collected in Palermo, Italy, during 2002–2004 did not react with the G2 type-specific RV5:3 monoclonal antibodies (MAbs) and could be identified as G2 only by RT-PCR genotyping. The genetic variation of VP7 and VP4 antigenic proteins was studied in 14 G2 samples including a selection of both those successfully characterized by serotyping and those failing to be serotyped. The phylogenetic analysis performed on partial VP7 sequences showed a temporal clustering of these strains, with those isolated in Palermo in 2003 belonging to the same lineage of G2 MAbs-unreactive strains identified in UK in 1996–1997 and in Bari, Italy, in 2003–2004. A single amino acid substi…
Analysis of early strains of the norovirus pandemic variant GII.4 Sydney 2012 identifies mutations in adaptive sites of the capsid protein.
2014
AbstractGlobal surveillance for norovirus identified in 2012 the emergence of a novel pandemic GII.4 variant, termed Sydney 2012. In Italy, the novel pandemic variant was identified as early as November 2011 but became predominant only in the winter season 2012–2013. Upon sequencing and comparison with strains of global origin, the early Sydney 2012 strains were found to differ from those spreading in 2012–2013 in the capsid (ORF2) putative epitopes B, C and D, segregating into a distinct phylogenetic clade. At least three residues (333, 340 and 393, in epitopes B, C and D, respectively) of the VP1 varied among Sydney 2012 strains of different clades. These findings suggest that the spread …
Epidemiological dynamics of norovirus GII.4 variant New Orleans 2009.
2015
Norovirus (NoV) is one of the major causes of diarrhoeal disease with epidemic, outbreak and sporadic patterns in humans of all ages worldwide. NoVs of genotype GII.4 cause nearly 80–90 % of all NoV infections in humans. Periodically, some GII.4 strains become predominant, generating major pandemic variants. Retrospective analysis of the GII.4 NoV strains detected in Italy between 2007 and 2013 indicated that the pandemic variant New Orleans 2009 emerged in Italy in the late 2009, became predominant in 2010–2011 and continued to circulate in a sporadic fashion until April 2013. Upon phylogenetic analysis based on the small diagnostic regions A and C, the late New Orleans 2009 NoVs circulati…
The complete genome sequence of Lamium mild mosaic virus, a member of the genus Fabavirus
2013
Springer-Verlag Wien 2013 Abstract Lamium mild mosaic virus (LMMV) is the only one of the five members of the genus Fabavirus for which there are no nucleotide sequence data. In this study, the complete genome sequence of LMMV was determined and compared with the available complete genome sequences of other members of the genus Fabavirus. The genome was the largest of the genus but maintained the typical orga- nization, with RNA 1 of 6080 nucleotides (nt), RNA 2 of 4065 nt, and an unusually long 3 0 untranslated region in RNA 2 of 603 nt. Phylogenetic analysis of the amino acid sequences of the protease-polymerase (Pro-Pol) region and the two coat proteins confirmed that LMMV belongs to a d…
Surface-exposed Amino Acid Residues of HPV16 L1 Protein Mediating Interaction with Cell Surface Heparan Sulfate
2007
Efficient infection of cells by human papillomaviruses (HPVs) and pseudovirions requires primary interaction with cell surface proteoglycans with apparent preference for species carrying heparan sulfate (HS) side chains. To identify residues contributing to virus/cell interaction, we performed point mutational analysis of the HPV16 major capsid protein, L1, targeting surface-exposed amino acid residues. Replacement of lysine residues 278, 356, or 361 for alanine reduced cell binding and infectivity of pseudovirions. Various combinations of these amino acid exchanges further decreased cell attachment and infectivity with residual infectivity of less than 5% for the triple mutant, suggesting …
Seroepidemiology of porcine enteric sapovirus in pig farms in Venezuela
2010
Porcine enteric sapovirus (PES) has been shown to cause diarrhea under experimental conditions in gnotobiotic piglets. However, the role of PES as enteric pathogens in porcine farms remains unclear. To further understand the PES-host interactions under field conditions, a serological survey was carried out. To this end the capsid gene of a PES isolate was cloned in the baculovirus expression system and an ELISA was developed based on virus-like particles from the baculovirus-expressed PES capsid protein. A total of 85 serum samples collected from pigs ranging from 8 weeks to over 54 weeks of age were analyzed. An overall seroprevalence to PESs of 62% was found, with significant differences …
Dendritic cell aggresome-like-induced structure formation and delayed antigen presentation coincide in influenza virus-infected dendritic cells.
2005
Abstract Influenza virus infection induces maturation of murine dendritic cells (DCs), which is most important for the initiation of an immune response. However, in contrast to EL-4 and MC57 cells, DCs present viral CTL epitopes with a delay of up to 10 h. This delay in Ag presentation coincides with the up-regulation of MHC class I molecules as well as costimulatory molecules on the cell surface and the accumulation of newly synthesized ubiquitinated proteins in large cytosolic structures, called DC aggresome-like-induced structures (DALIS). These structures were observed previously after LPS-induced maturation of DCs, and it was speculated that they play a role in the regulation of MHC cl…
The Transcription Factors TBX2 and TBX3 Interact with Human Papillomavirus 16 (HPV16) L2 and Repress the Long Control Region of HPVs
2013
ABSTRACT The minor capsid protein L2 of human papillomaviruses (HPVs) has multiple functions during the viral life cycle. Although L2 is required for effective invasion and morphogenesis, only a few cellular interaction partners are known so far. Using yeast two-hybrid screening, we identified the transcription factor TBX2 as a novel interaction partner of HPV type 16 (HPV16) L2. Coimmunoprecipitations and immunofluorescence analyses confirmed the L2-TBX2 interaction and revealed that L2 also interacts with TBX3, another member of the T-box family. Transcription of the early genes during HPV infection is under the control of an upstream enhancer and early promoter region, the long control r…
Quasispecies dynamics and molecular evolution of human norovirus capsid P region during chronic infection.
2009
In this novel study, we have for the first time identified evolutionarily conserved capsid residues in an individual chronically infected with norovirus (GGII.3). From 2000 to 2003, a total of 147 P1-1 and P2 capsid sequences were sequenced and investigated for evolutionarily conserved and functionally important residues by the evolutionary trace (ET) algorithm. The ET algorithm revealed more absolutely conserved residues (ACR) in the P1-1 domain (47/53, 88 %) as compared with the P2 domain (86/133, 64 %). The capsid P1-1 and P2 domains evolved in time-dependent manner, with a distinct break point observed between autumn/winter of year 2000 (isolates P1, P3 and P5) and spring to autumn of y…
PML nuclear body-residing proteins sequentially associate with HPV genome after infectious nuclear delivery.
2019
Subnuclear promyelocytic leukemia (PML) nuclear bodies (NBs) are targeted by many DNA viruses after nuclear delivery. PML protein is essential for formation of PML NBs. Sp100 and Small Ubiquitin-Like Modifier (SUMO) are also permanently residing within PML NBs. Often, large DNA viruses disassemble and reorganize PML NBs to counteract their intrinsic antiviral activity and support establishment of infection. However, human papillomavirus (HPV) requires PML protein to retain incoming viral DNA in the nucleus for subsequent efficient transcription. In contrast, Sp100 was identified as a restriction factor for HPV. These findings suggested that PML NBs are important regulators of early stages o…