Disease relevance of RPVgp5

• Based on the crystal structure of the NDV F protein, we then predicted the locations of the Morbillivirus glycans: the glycan at position 36 is located in the F protein head, and those at positions 68 and 75 are located near the neck-stalk interface [1].
• The H polypeptide has receptor-binding and hemagglutinating activity, whereas the F protein mediates virus penetration of the host cell, formation of syncytia, and hemolysis of erythrocytes [2].
• When expressed from a recombinant vaccinia virus in primate cells infected by MV, the engineered serpin (alpha 1-PDX) specifically inhibited furin-catalyzed cleavage of the F-protein precursor without affecting synthesis of other MV proteins [3].
• The uncleaved precursor F0 and the F1 subunit from infected cells and extracellular virus were both labeled, indicating that palmitoylation can take place prior to F0 cleavage and that palmitoylated F protein was incorporated into virus particles [4].
• Immunization of dogs with measles virus (MV) iscoms, prepared either from affinity-purified MV F protein or from purified whole virus, resulted in partial protection against challenge with CDV [5].

High impact information on RPVgp5

• On the other hand, the long 5' UTR of the F mRNA was found to possess the capacity to decrease the F protein production, inhibiting virus replication and yet greatly reducing cytopathogenicity [6].
• NDV position 36 is not occupied by a glycan; the only glycan in that F protein head also has a fusion control function and grows from residue 366, located only 6 A from residue 36 [1].
• To investigate the role of H protein in the differential MV host cell specificity and cell fusion activity, H proteins of wild-type MV (IC-B) and Ed were coexpressed with the F protein in Vero cells [7].
• In the intracellular neutralization experiments, confocal immunofluorescence microscopy showed prominent colocalization of anti-H IgA and H protein inside virus-infected cells, whereas colocalization of anti-F and F protein and of anti-N and N protein was much less, in agreement with the neutralization results [8].
• The pseudotype bearing the wild-type KA H protein and Edmonston F protein (VSVDeltaG*-KAHF) infected all lymphoid cell lines in which the wild-type MV strains caused CPE as efficiently as VSVDeltaG*-EdHF, but it did not infect any of the cell lines resistant to infection with the KA strain [9].

Chemical compound and disease context of RPVgp5

• Fusion glycoprotein (F) of rinderpest virus: entire nucleotide sequence of the F mRNA, and several features of the F protein [10].
• The homology of the amino acid sequence of the F protein between the MV and SSPE virus was 96.27%, and the positions of cysteine and proline were almost identical in the two viruses [11].

Biological context of RPVgp5

• These results suggest that the F protein transmembrane domain cysteines 506 and 518 participate in structures involved in cell fusion, possibly mediated by palmitoylation [4].
• Glycosylation of the proteins appeared to be impaired somewhat, and the precursor to the F protein was not completely cleaved by the proteases present in insect host cells [2].
• The data indicate that the arginine 112 residue is critical for the correct proteolytic cleavage that is required for the membrane fusion activity of the MV F protein [12].
• No changes were found in the F protein which could explain attenuation of the vaccine; however, each of the mild field isolates had amino acid changes in important functional areas which may be related to their attenuated phenotype [13].
• Previous studies from this laboratory showed that oligopeptides with amino acid sequences similar to the sequence of the N-terminal region of the F1 polypeptide of paramyxoviruses inhibited the membrane fusing activity of the F protein, and thereby inhibited virus infectivity at the level of penetration and virus-induced cell fusion and hemolysis [14].

Anatomical context of RPVgp5

• This aberrant cleavage appears to have abolished the ability of the F protein to cause syncytium formation [12].
• As an alternative to detecting physical associations of these proteins by coimmunoprecipitation, further studies were performed with a mutant HPIV3 F protein (F-KDEL) lacking a transmembrane anchor and cytoplasmic tail and containing a carboxyl-terminal retention signal for the endoplasmic reticulum (ER) [15].
• Accordingly, no F protein could be detected in the HNT-PI cell line, although both the M and H proteins were produced in amounts comparable to those of Ph26 [16].
• We concluded that the distribution of hydrophobic regions capable of spanning biological membranes determines the fusogenic nature of the F protein [17].
• The F protein of both the Edmonston strain and a wild-type MV was found to be cleaved in the trans-Golgi cisternae and/or the trans-Golgi network (TGN) [18].

Associations of RPVgp5 with chemical compounds

• As revealed by our previous studies, proteolytic cleavage of the MV F protein precursor into its F1 and F2 subunits, but not of F/H-mediated cellular fusion, was found to be required, since fusion-inhibitory peptides such as Z-D-Phe-L-Phe-Gly (Z-fFG) did not interfere with the induction of proliferative inhibition [19].
• [3H]palmitic acid was released from F protein upon hydroxylamine or dithiothreitol treatment, indicating a thioester linkage [4].
• These results and previous findings that formalin-treated virus does not induce antibodies to F protein provide an explanation for atypical measles [20].
• Treatment of MV or Ad5MVF-infected cells with tunicamycin, an inhibitor of N-linked glycosylation, abolished processing of the F protein [21].
• CSP reduced the detection of the MV F protein by certain monoclonal antibodies (MAbs) that appeared to recognize nonlinear epitopes [22].

Other interactions of RPVgp5

• The synthesis of H, N and possibly F protein was seen in both lytic and persistent infections, but the synthesis of M protein was only detected in the lytic infection [23].
• In acute and subacute lesions without associated inflammation, expression of the M, H and F protein was only slightly diminished compared to the N and P protein [24].

Analytical, diagnostic and therapeutic context of RPVgp5

• To investigate the role of the arginine residue at the carboxy terminus of the F2 subunit (arginine 112), site-directed mutagenesis was used to construct a cleavage mutant of the MV F protein in which this arginine residue was changed to a leucine residue [12].
• When transiently expressed in cell cultures standard F protein was cleaved, whereas the mutant remained in the uncleaved form [25].
• Sequence analysis predicts a mutation in the cleavage recognition sequence, a truncated carboxyl-terminus, and multiple mutations in F1 of the Biken F protein [26].
• Intracellular processing of measles virus fusion (F) protein was studied by radiolabeling and immunoprecipitation with a monoclonal antibody against F protein [27].
• Cocultivation of Cos cells expressing the wild-type H protein and the Edmonston strain F protein with B95a cells, but not with HeLa, Jurkat or BJAB cells, generated large syncytia [28].

References