Disease relevance of N

• Analysis of primary transcription of the two rhabdoviruses showed that there was lower expression level and copy number of the viral nucleoprotein transcript in the JFMx-transfected cell line than the infected, control cells, although no significant difference was observed [1].
• Results obtained using genomic or messenger virus RNA as a probe indicated that the middle part of N was possibly an RNA-binding domain [2].
• The gene encoding the nucleoprotein (N) and PCR-derived subfragments from viral haemorrhagic septicaemia virus (VHSV), a salmonid rhabdovirus, were overexpressed in Escherichia coli BL21(DE3) transformed by recombinant expression vector pET-14b containing N and PCR-generated sub-fragment cDNAs under the control of the T7 RNA polymerase promoter [2].
• Cotransfections of the negative sense minigenome plasmids with plasmids encoding nucleoprotein (N), phosphoprotein (P) and RNA polymerase (L) of IHNV and VHSV were carried out in all combinations [3].
• An RNA-binding domain in the viral haemorrhagic septicaemia virus nucleoprotein [2].

High impact information on N

• Kinetics of rhabdovirus expression by RT-PCR and quantitative real-time RT-PCR showed reduced levels of the rhabdoviral glycoprotein and nucleoprotein transcripts over time, indicating the possible role of JFMx in blocking rhabdoviral replication by interfering with the transcription of the viral subgenomic mRNAs [1].
• All these experiments led us to conclude that the middle part of N is the domain which interacts with RNA, despite the absence of homology with known consensus amino acid sequences of other RNA-binding proteins [2].
• The nucleotide sequences of a specific region of the nucleoprotein gene were compared in order to investigate the genetic population structure of marine viral haemorrhagic septicaemia virus (VHSV) [4].
• Phylogenetic analysis of nucleoprotein gene sequences confirmed the existence of the 4 major genotypes previously identified based on N- and subsequent G-gene based analyses [4].
• Replication of VHSV in the stromal cell cultures was demonstrated by the increase in infectivity by epithelioma papulosum cyprini (EPC) cell culture assays and by the increase of the nucleoprotein antigen of VHSV by ELISA [5].

Biological context of N

• VHSV N gene amplification was more efficient and more sensitive than the VHSV G amplicon [6].
• Sequence analysis of the entire nucleoprotein and glycoprotein genes revealed the virus was a member of the North American genotype of VHSV; however, the isolate was sufficiently distinct to be considered a separate sublineage, suggesting its origin may have been from marine species inhabiting the eastern coastal areas of the USA or Canada [7].
• Minigenome constructs were expressed only after cotransfection with a set of helper plasmids (N, P and L) all originated from one virus [3].
• A ribonuclease (RNase) protection assay (RPA) has been used to detect nucleotide sequence variation within the nucleoprotein gene of 39 viral haemorrhagic septicaemia virus (VHSV) isolates of European marine origin [8].

Analytical, diagnostic and therapeutic context of N

• That Nx protein is antigenically related to the nucleoprotein of purified virus was shown by its reaction with four anti-nucleoprotein monoclonal antibodies (at least 3 of them reacting non competitively against different epitopes) and by immunoprecipitation with polyvalent international reference sera [9].

References