Disease relevance of N

• By DNA-mediated gene transfer into a line of simian virus 40-transformed monkey kidney cells, the N-specific cDNA was expressed into a single polypeptide of about 60,000 Mr, which was immunoprecipitated by monoclonal antibodies against the measles virus N protein [1].
• When the nucleotide and deduced amino acid sequences of the N, P, V and C genes were aligned with corresponding sequences of other established members of the morbillivirus genus, compelling homology was found between PDV and canine distemper virus (CDV), whereas there was markedly less similarity between PDV and measles virus or rinderpest virus [2].
• As with other morbilliviruses, the phosphoprotein (P) gene of PDV was found to be located after the 5' end of the N gene and before the 3' end of the matrix protein gene [2].
• CONCLUSIONS: This study shows that discrimination between SSPE and MS can be achieved in doubtful cases by IEF using MV-N, P and F proteins [3].
• Key words: Peste-des-petits-ruminants virus; PCR; RT-PCR; M gene; N gene; H gene; F gene; multiplex PCR [4].

High impact information on N

• These data demonstrate that MV NP binds to human and murine FcgammaRII and inhibits in vitro antibody production, and therefore suggests a role for NP in MV-induced immunosuppression [5].
• By flow cytometry, we showed that viral or recombinant NP bound to human and murine B lymphocytes, but not to T lymphocytes [5].
• This fusion results in envelope hemagglutinin (H) and fusion glycoprotein (F) incorporated into the plasma membrane and injection of the nucleocapsid made of nucleoprotein (NP) into the cytosol [6].
• Osteoclasts expressing the measles virus nucleocapsid gene display a pagetic phenotype [7].
• In the presence of cytochalasin B (1--2 micrograms/ml), co-capping of the matrix protein was unchanged or slightly enhanced, whereas co-capping of the nucleocapsid protein decreased, indicating that actin filaments may mediate the communication between viral nucleocapsids and the cell membrane [8].

Chemical compound and disease context of N

• Overall, the NP and in particular the F proteins of the morbilliviruses showed a high degree of epitopic homology; the P and M proteins showed a partial epitopic homology, with the greatest variation between the M proteins of CDV and MV; the H proteins showed a low degree of epitopic homology and then only between MV and RPV [9].
• Target sequences of measles virus nucleocapsid (N) and phosphoprotein genes were detected within measles virus infected Vero cells, both in suspension and in formalin-fixed sections, that had been treated by in situ reverse transcription and 30 cycles of direct in situ PCR [10].
• Tyrosine phosphorylation of measles virus nucleocapsid protein in persistently infected neuroblastoma cells [11].
• SDS greatly decreased the reactivity of measles virus nucleocapsid but Triton X-100 and, to a larger degree, sodium deoxycholate released antigen from the cells in quantities greater than that detected when no detergent pretreatment was employed [12].
• After infection of CEM174.T2 cells [deficient for the transporter of antigen presentation (TAP)] with measles virus (MV) the nucleocapsid protein is recognized by L(d)-restricted cytotoxic T cells in a TAP-independent, chloroquine-sensitive fashion [13].

Biological context of N

• RNA interference with measles virus N, P, and L mRNAs efficiently prevents and with matrix protein mRNA enhances viral transcription [14].
• On the basis of the alignments presented, the estimated amino acid sequence similarity between the N and P genes of PDV and CDV was 84% and 76%, respectively [2].
• Identification of three lineages of wild measles virus by nucleotide sequence analysis of N, P, M, F, and L genes in Japan [15].
• The long open reading frame of the gene encoding the nucleocapsid (N) protein is presented [2].
• PCR products of the N and H regions were sequenced and we confirmed the presence of measles genome [16].

Anatomical context of N

• In radioimmunoprecipitation assays two of the Fabs, MV12 and MT14, precipitated an approximately equal 80-kDa protein band corresponding to the hemagglutinin (H) protein from MV-infected Vero cell cultures, while two other Fabs, MT64 and GL29, precipitated an approximately equal 60-kDa protein corresponding the nucleocapsid (N) protein [17].
• Rabbit antisera monospecific for measles virus matrix and nucleocapsid proteins and a human antiserum containing specificities for both the hemagglutinin and hemolysin proteins were used to study the co-capping of these proteins in human Lu 106 cell-line, chronically infected with measles virus [8].
• T cells from BALB/c mice that are resistant to measles virus encephalitis proliferate well against measles virus in vitro, and bulk cultures recognize viral nucleocapsid and hemagglutinin as well as fusion proteins [18].
• The humoral immune response in sera and cerebrospinal fluids (CSFs) of dogs with various forms of canine distemper virus (CDV)-induced encephalitis was assessed by immunoprecipitation of radiolabelled nucleocapsid, phosphoprotein, membrane (M), haemagglutinin and fusion proteins [19].
• The two innermost proteins, the nucleocapsid and polymerase proteins, also appeared to be antigenically stable as no variation was detected between strains using in each case a panel of six hybridomas [20].

Associations of N with chemical compounds

• These cross-reactivities and type-specific reactions were obtained with the internal viral proteins (M, P and NP) [9].
• Affinity purified GST-NP fusion protein has been used as a probe to examine the interaction of NP with [35S] methionine labeled proteins from MV-infected cells [21].
• Children immunized with inactivated (Tween 80 and diethyl ether, TE) measles vaccine, attenuated live vaccine, or a combination of the two types were studied with regard to the production of hemagglutination-inhibiting (HAI), hemolysis-inhibiting (HLI), and nucleocapsid complement-fixing (CF) antibodies [22].
• The free N-protein is phosphorylated only on serine residues, whereas the nucleocapsid-associated N-protein is phosphorylated on both serine and threonine residues [23].

Regulatory relationships of N

• Moreover, considerably less measles virus nucleocapsid was required to stimulate a comparable CTL response than the measles virus hemagglutinin which suggests that the CTL response to measles virus may be skewed towards internal viral determinants of measles virus [24].
• Measles virus nucleocapsid protein expressed in insect cells assembles into nucleocapsid-like structures [25].

Other interactions of N

• The viral polymerase associates with the nucleocapsid through a small, trihelical binding domain at the carboxyl terminus of the phosphoprotein (P) [26].
• By the immunofluorescence test, hemagglutinin, nucleocapsid-associated phosphorylated, and fusion proteins were found only in the cytoplasm of cells infected with the virus at a low passage level [27].

Analytical, diagnostic and therapeutic context of N

• Additionally, immunoprecipitation experiments demonstrated that hPIRH2-myc, MV P, and nucleocapsid (N) proteins form a ternary complex [28].
• In addition, N-specific Fabs bound to denatured MV N protein in Western blotting [17].
• In 28 patients with natural measles infection a single step PCR amplifying the N region resulted in a high detection rate for all plasma samples (28/28) within 3 days of the onset of rash and 80% (20/25) even on day 7 of the onset of rash and later [16].
• A simple and sensitive method for the detection of measles virus genome was developed, amplifying the regions encoding the nucleocapsid (N) protein and hemagglutinin (H) protein of measles virus by reverse transcriptase-polymerase chain reaction (RT-PCR) [16].
• Distribution of measles virus within infected cells was determined by in situ hybridisation and immunocytochemistry for measles virus N gene and protein, respectively [10].

References