Molecular cloning of a full-length cDNA encoding the hemagglutinin-neuraminidase glycoprotein of Sendai virus

Wheat germ cell-free system-based production of hemagglutinin-neuraminidase glycoprotein of human parainfluenza virus type 3 for generation and characterization of monoclonal antibody

Human parainfluenza virus 3 (HPIV3) commonly causes respiratory disorders in infants and young children. Monoclonal antibodies (MAbs) have been produced to several components of HPIV3 and commercially available. However, the utility of these antibodies for several immunological and proteomic assays for understanding the nature of HPIV3 infection remain to be characterized. Herein, we report the development and characterization of MAbs against hemagglutinin-neuraminidase (HN) of HPIV3. A recombinant full-length HPIV3-HN was successfully synthesized using the wheat-germ cell-free protein production system. After immunization and cell fusion, 36 mouse hybridomas producing MAbs to HPIV3-HN were established. The MAbs obtained were fully characterized using ELISA, immunoblotting, and immunofluorescent analyses. Of the MAbs tested, single clone was found to be applicable in both flow cytometry and immunoprecipitation procedures. By utilizing the antibody, we identified HPIV3-HN binding host proteins via immunoprecipitation-based mass spectrometry analysis. The newly-developed MAbs could thus be a valuable tool for the study of HPIV3 infection as well as the several diagnostic tests of this virus.

Decoy against nuclear factor-kappa B attenuates myocardial cell infiltration and arterial neointimal formation in murine cardiac allografts

Acute rejection and graft arteriopathy in cardiac transplantation limit the long-term survival of recipients; these processes are enhanced by several cytokines and adhesion molecules. Nuclear factor-kappa B (NFkappaB) is critical in the transcription of multiple genes involved in inflammation and cell proliferation. To test the hypothesis that NFkappaB decoy can attenuate acute rejection and arteriopathy, we performed single intraluminal delivery of NFkappaB decoy into murine cardiac allografts using a hemagglutinating virus of Japan (HVJ)-artificial viral envelope (AVE)-liposome method. No decoy or scrambled decoy transfer was performed for control. Hearts were heterotopically transplanted from BALB/c to C3H/He mice (major mismatch group) and from DBA/2 to B10.D2 mice (minor mismatch group). Nontreated or scrambled decoy transfected allografts of the major mismatch group were acutely rejected, while NFkappaB decoy prolonged their survival. While severe cell infiltration and intimal thickening with enhancement of inflammatory factors were observed in untreated or scrambled decoy-treated allografts of minor mismatch group at day 28, NFkappaB decoy attenuated these changes. We conclude that NFkappaB is critically involved in the development of acute as well as chronic rejection of the transplanted hearts. NFkappaB decoy attenuates both acute rejection and graft arteriopathy by blocking the activation of several genes.

Determination of the disulfide bond arrangement of Newcastle disease virus hemagglutinin neuraminidase. Correlation with a beta-sheet propeller structural fold predicted for paramyxoviridae attachment proteins

Disulfide bonds stabilize the structure and functions of the hemagglutinin neuraminidase attachment glycoprotein (HN) of Newcastle disease virus. Until this study, the disulfide linkages of this HN and structurally similar attachment proteins of other members of the paramyxoviridae family were undefined. To define these linkages, disulfide-linked peptides were produced by peptic digestion of purified HN ectodomains of the Queensland strain of Newcastle disease virus, isolated by reverse phase high performance liquid chromatography, and analyzed by mass spectrometry. Analysis of peptides containing a single disulfide bond revealed Cys(531)-Cys(542) and Cys(172)-Cys(196) linkages and that HN ectodomains dimerize via Cys(123). Another peptide, with a chain containing Cys(186) linked to a chain containing Cys(238), Cys(247), and Cys(251), was cleaved at Met(249) with cyanogen bromide. Subsequent tandem mass spectrometry established Cys(186)-Cys(247) and Cys(238)-Cys(251) linkages. A glycopeptide with a chain containing Cys(344) linked to a chain containing Cys(455), Cys(461), and Cys(465) was treated sequentially with peptide-N-glycosidase F and trypsin. Further treatment of this peptide by one round of manual Edman degradation or tandem mass spectrometry established Cys(344)-Cys(461) and Cys(455)-Cys(465) linkages. These data, establishing the disulfide linkages of all thirteen cysteines of this protein, are consistent with published predictions that the paramyxoviridae HN forms a beta-propeller structural fold.

Genetic characterization of parainfluenza virus 3 derived from guinea pigs

To understand the relationship between novel parainfluenza virus 3 (PIV-3), which has recently been isolated from the lungs of guinea pigs, and other PIV-3 strains, we determined the complete nucleotide sequence of the novel PIV-3 (GPv) genome. A comparison of the nucleotide sequence among PIV-3s, including bovine PIV-3, revealed that GPv is closely related to human PIV-3. The results of the phylogenetic analysis clearly showed that GPv is a lineage of human PIV-3, suggesting that GPv has probably been introduced into guinea pig colonies via infected humans.

Sequence and structure alignment of paramyxovirus hemagglutinin-neuraminidase with influenza virus neuraminidase

A model is proposed for the three-dimensional structure of the paramyxovirus hemagglutinin-neuraminidase (HN) protein. The model is broadly similar to the structure of the influenza virus neuraminidase and is based on the identification of invariant amino acids among HN sequences which have counterparts in the enzyme-active center of influenza virus neuraminidase. The influenza virus enzyme-active site is constructed from strain-invariant functional and framework residues, but in this model of HN, it is primarily the functional residues, i.e., those that make direct contact with the substrate sialic acid, which have identical counterparts in neuraminidase. The framework residues of the active site are different in HN and in neuraminidase and appear to be less strictly conserved within HN sequences than within neuraminidase sequences.

The haemagglutinin-neuraminidase glycoprotein of the porcine paramyxovirus LPMV: comparison with other paramyxoviruses revealed the closest relationship to simian virus 5 and mumps virus

The complete nucleotide sequence of the haemagglutinin-neuraminidase (HN) gene of the porcine paramyxovirus LPMV, was determined from cDNA derived from viral genomic RNA. The gene was 1906 nucleotides long including a putative gene end and poly A signal. One long open reading frame was found encoding a protein of 576 amino acids with a calculated molecular weight of 63,324. The protein contains four potential N-glycosylation sites and a major hydrophobic region near the N-terminal, suggesting a membrane anchor domain. Comparison of the deduced amino acid sequence of the LPMV HN protein with that of other paramyxovirus HN proteins, revealed the highest amino acid identity to simian virus 5 of 43% and mumps virus of 41%.

Nucleotide sequence analyses of the genes encoding the HN, M, NP, P, and L proteins of two host range mutants of Sendai virus

Comparative nucleotide sequence analyses of the genome of Sendai virus (strain Z) and two host range mutants, ts-f1 and F1-R, previously described revealed that the ts defect of ts-f1 can be attributed to two nucleotide exchanges in the NP gene. These exchanges lead to a single amino acid substitution. A single base pair change was found in both the P and L genes of F1-R, but not of ts-f1. Both host range mutants have the two same exchanges in the M gene. These additional mutations are discussed concerning their significance in the pantropic properties of the host range mutants.

Molecular cloning and sequence analysis of human parainfluenza type 4A virus HN gene: its irregularities on structure and activities

We cloned the cDNA of human parainfluenza type 4A virus (PIV-4A) HN gene by reverse-transcription of virus-specific mRNAs and genomic RNA, and determined the complete nucleotide sequence of the HN gene. The predicted HN protein sequence of PIV-4A showed significant relatedness with those of other paramyxoviruses, SV5, NDV, MuV, PIV-3, BPIV-3, indicating a common ancestor. The homologies between the viruses suggested that PIV-4A is more closely related to NDV, SV5, and MuV than to the parainfluenza viruses, PIV-3, bovine parainfluenza type 3 virus (BPIV-3), and Sendai virus (SV). Sixty amino acids were commonly conserved among the viruses, other than PIV-4A. Two of these amino acids were substituted in PIV-4A HN and are predicted to be located near the active site of the neuraminidase. The analysis of neuraminidase of PIV-4 revealed that the activity is hardly detectable, suggesting the significant effect of the substituted amino acid sites on neuraminidase activity.

Sequence determination of the hemagglutinin-neuraminidase (HN) gene of human parainfluenza type 2 virus and the construction of a phylogenetic tree for HN proteins of all the paramyxoviruses that are infectious to humans

The nucleotide sequence of the hemagglutinin-neuraminidase (HN) gene of human parainfluenza type 2 virus (PIV-2) was determined. The PIV-2 HN gene was 2112 nucleotides excluding poly(A) tail. There was a single large open reading frame in the mRNA which encoded a protein of 571 amino acids with a calculated molecular weight of 63,262. Analysis of the deduced amino acid sequence revealed that there were fourteen potential glycosylation sites and a major hydrophobic region near the N-terminus, which would anchor the protein in the viral membrane. Comparisons of the HN protein sequences of PIV-2 with those of Simian virus 5 (SV5), Sendai virus (SV, parainfluenza virus type 1), human parainfluenza virus type 3 (PIV-3), type 4 (PIV-4), bovine parainfluenza virus type 3 (BPIV-3), mumps virus (MuV), and Newcastle disease virus (NDV) showed definite amino acid sequence relatedness, indicating a common ancestor for these viruses. Furthermore, statistical analysis of the protein sequences suggested a possible evolutionary relatedness among the paramyxoviruses. This is the first time that a phylogenetic tree has been constructed for all the parainfluenza viruses and mumps virus which are infectious to humans. In addition, amino acid sequences involved in hemagglutinating and neuraminidase activities of paramyxovirus were discussed.

Conserved sequences in bacterial and viral sialidases

The genes of the bacterial sialidases from Clostridium sordellii G12, C. perfringens A99, Salmonella typhimurium LT-2 and Vibrio cholerae 395 sequenced so far were examined for homologies and were compared with sequences of viral sialidases. Each of the bacterial sialidases contains a short sequence of twelve amino-acids, which is repeated at four positions in the protein. All these sequences exhibit significant similarities. Comparing the repeated sequences of the four sialidases, five amino-acids were found to be highly conserved at defined positions: Ser-X-Asp-X-Gly-X-Thr-Trp. Additionally, most of the distances between the four repeated regions are also conserved among the different sialidases. The conserved bacterial sequences show similarity with sialidases of influenza A H7N1 and H13N9.

Newcastle disease virus evolution. I. Multiple lineages defined by sequence variability of the hemagglutinin-neuraminidase gene

We compared the hemagglutinin-neuraminidase gene sequence among 13 strains of Newcastle disease virus (NDV) isolated over the last 50 years. Although overall homology was remarkably high, the sequence variability demonstrated the existence of at least three distinct lineages, which must have co-circulated for considerable periods. The sequence variability also appears to reflect some accumulation of mutations over time. Strictly correlating with the lineages, the translation products could be classified into three size classes. One class lacked the interchain disulfide bond, and another represented unusual precursor protein of biologically inactive form. The lineages correlated to some extent with virulence and place of isolation of the strains. However, antigenic variations, which were neither cumulative nor progressive, did not correlate with the lineages. These analyses showing multiple lineages were greatly facilitated by a precise calculation of synonymous substitutions, which had been largely free from selective pressures and had occurred frequently and evenly throughout the coding region.

Isolation of a biologically active soluble form of the hemagglutinin-neuraminidase protein of Sendai virus

As a first step in establishing the three-dimensional structure of the Sendai virus hemagglutinin-neuraminidase (HN), we have isolated and characterized a potentially crystallizable form of the molecule. The sequence of HN, a surface glycoprotein, predicts a protein with an uncharged hydrophobic region near the amino terminus which is responsible for anchorage in the viral envelope. To avoid rosette formation (aggregation), which would preclude crystallization, this hydrophobic tail was removed from a membrane-free form of HN by proteolytic digestion. This digestion resulted in a single product with a molecular weight of about 10,000 less than native HN. N-terminal amino acid sequence analysis of cleaved HN (C-HN) indicated a single cleavage site at amino acid residue 131, resulting in a product consisting of the carboxyl-terminal 444 amino acids of HN. Functional analyses revealed that C-HN retained full neuraminidase activity and was able to bind erythrocytes, indicating that the N-terminal 131 residues were not necessary for these biological activities. Furthermore, this cleavage product retained the antigenic structure of intact HN, since monoclonal antibodies still bound to C-HN in enzyme-linked immunosorbent assay and Western (immuno-) blot analysis. Viewed by electron microscopy, the dimeric and tetrameric forms of intact HN form rosettes while C-HN maintains the oligomeric structure but no longer aggregates. Furthermore, the electron micrographs revealed a C-HN tetramer strikingly similar to the influenza virus neuraminidase in both size and gross structural features.

Introduction of macromolecules into mammalian cells by cell fusion

Proteins with molecular weights of up to 500K can be enclosed in erythrocyte ghosts by exposing the ghosts to hypotonic solution containing these proteins. The proteins can then be introduced into recipient cells by fusing the ghosts with the cells using HVJ, PEG, or influenza virus. Some applications of this method are described. By an improved method, 15 kbp DNA and IgM (900 kDa) can be entrapped in erythrocyte membranes and these are then treated with liposomes containing gangliosides and HVJ. These treated membranes containing large macromolecules fuse with almost 100% of the recipient cells used. Naked liposomes infrequently fuse with cultured cells, so introduction of their contents into cells is very inefficient. However, liposomes constituted from lipid and glycoproteins (HN and F) of HVJ (Sendai virus), by removing a nonionic detergent, fuse with cells about 200 times more efficiently than naked liposomes. Naked liposomes can fuse with specific cells, such as cells infected with subacute sclerosing panencephalitis virus or with human immunodeficiency virus. Plasmid DNA and mRNA of up to about 40 kbp can be entrapped efficiently in liposomes associated with gangliosides formed by reverse-phase evaporation, and then reacted with HVJ. The contents of the resulting liposomes with HVJ can be introduced efficiently into cultured cells in a suspended or plated state, and nearly all the cells then express the gene transiently. This procedure is also effective for obtaining stable transformants of many kinds of cultured cells.

Differences in bovine parainfluenza 3 virus variants studied by sequencing of the genes of viral envelope proteins

By determining gene nucleotide sequences we compared the primary structures of the membrane (M), fusion (F), and hemagglutinin-neuraminidase (HN) proteins of bovine parainfluenza 3 virus strains, M, SC, and MR which are substrains derived from a wild strain YN. The M and SC viruses are indistinguishable in having very weak hemagglutination (HA) and neuraminidase (NA) activities, but M virus' syncytium-inducing (SI) activity is considerably higher than that of the SC virus. However, the results showed that the amino acid sequence of the F protein was identical in M and SC viruses, demonstrating that M virus' high SI activity was not due to alteration of its F protein. Two differences in M and SC viruses' other proteins then seemed to be important, although their significance in the SI activity is not clear at present; the first being the 70th amino acid residue of the M protein, which was Asp in the M virus and Gly in the SC virus, and the other being the 539th residue of the HN protein, which was Tyr in the M virus and His in the SC virus. The nucleocapsid proteins of both M and SC viruses were identical. The MR virus, which is a variant derived from the M virus and has high HA and NA activities but very weak SI activity, was different from the M virus at only one site throughout the M, F, and HN proteins; the 193rd amino acid residue of the HN protein was Leu in the MR virus and Phe in the M virus. This result strongly suggested that the substitution of Leu with Phe at this particular site was closely linked to the drastic reduction in both HA and NA activities.

Nucleotide sequence of the bovine parainfluenza 3 virus genome: its 3' end and the genes of NP, P, C and M proteins

We present the nucleotide sequence of bovine parainfluenza 3 virus (BPIV3) genome from its 3' end to the opening region of the F gene, through the NP, P plus C, and M genes. Comparison of the sequence with those reported for other paramyxoviruses indicated that BPIV3 was most similar to human parainfluenza 3 virus (HPIV3), and also very similar to Sendai virus in the structural make-up of its genome and the amino acid sequences of its gene products, suggesting that these three viruses constitute a paramyxovirus subgroup from which Newcastle disease and measles viruses are separable. In BPIV3 and Sendai virus, the NP and M proteins, the main structural elements, were more highly conserved than the functionally important P and C proteins. This tendency was also observed even in BPIV3 and HPIV3. Virus-specific amino acid sequences of the NP and M proteins were found at the carboxyl and amino terminal regions, respectively. BPIV3 M mRNA was found to have aberrations in its poly A attachment site.

Nucleotide sequence of the bovine parainfluenza 3 virus genome: the genes of the F and HN glycoproteins

By analysing complementary DNA clones constructed from genomic RNA of bovine parainfluenza 3 virus (BPIV3), we determined the nucleotide sequence of the region containing the entire F and HN genes. Their deduced amino acid sequences showed about 80% homologies with those of human parainfluenza 3 virus (HPIV3), about 45% with those of Sendai virus, and about 20% with those of SV5 and Newcastle disease virus (NDV), indicating, together with the results described in the preceding paper on the NP, P, C and M proteins of BPIV3, that BPIV3, HPIV3 and Sendai virus constitute a paramyxovirus subgroup, and that BPIV3 and HPIV3 are very closely related. The F and HN proteins of all these viruses, including SV5 and NDV, however, were shown to have protein-specific structures as well as short but well-conserved amino acid sequences, suggesting that these structures and sequences are related to the activities of these glycoproteins.

The hemagglutinin-neuraminidase (HN) gene of Newcastle disease virus strain Italien (ndv Italien): comparison with HNs of other strains and expression by a vaccinia recombinant

A cDNA library was constructed with poly(A+) mRNA from cells infected with the virulent Italien NDV strain. A clone that hybridized to the HN gene mRNA was sequenced. A long open reading-frame encodes for a protein of 571 amino acids, with a calculated molecular weight of 61,900, including 13 cysteine residues and six potential glycosylation sites. To define the sequence changes that occurred in the avian paramyxovirus hemagglutinin-neuraminidase (HN) during the evolution of virulence, we have studied the HNs of the virulent Italien NDV strain, the mesovirulent Beaudette strain and the nonvirulent Hitchner strain. The majority of amino acid variations are conservative changes but they cluster at 4 preferential sites in the putative head of HN. The clusters of amino acid substitutions are intimately associated or overlap with regions of HN rich in charged amino acid residues and in cysteines. The latter are conserved not only between HNs from all 3 NDV strains but also between HNs of 4 different paramyxoviruses, NDV, SV 5, Sendai and PI 3. The HN coding sequence was inserted into the genome of vaccinia virus under the control of vaccinia P 7.5 K transcriptional regulatory sequences. Expression of native HN proteins at the surface of recombinant HN vaccinia-infected cells was demonstrated by indirect immunofluorescence with 2 anti-HN monoclonals.

Sequence of the Sendai virus L gene: open reading frames upstream of the main coding region suggest that the gene may be polycistronic

The sequence of the L gene of Sendai virus, encompassing 6799 nucleotides, has been determined, completing the primary sequence of the entire virus genome. An open reading frame beginning at position 569 codes for a basic protein of 2048 amino acids with an estimated Mr of 231,608. No nucleotide sequence similarities with the analogous L gene of vesicular stomatitis virus were observed. However, comparison of the deduced amino acid sequences of both proteins revealed a conserved 18 amino acid sequence that may have functional significance. Two additional overlapping reading frames which precede the L protein sequence could encode proteins with MrS of 6474 and 14,026, suggesting that the gene is polycistronic.

Determination of the complete nucleotide sequence of the Sendai virus genome RNA and the predicted amino acid sequences of the F, HN and L proteins

We previously determined the 3' proximal 5,824 nucleotides of the Sendai virus genome RNA (Nucleic Acids Res. 11, 7317-7330, 1983; Nucleic Acids Res. 12, 7965-7973, 1984), and present here the sequence of the remaining 5' proximal 9,559 nucleotides. Thus, this is the first paramyxovirus to have its genome organization elucidated. The set of complementary DNA clones used was prepared by the method of Okayama and Berg from polyadenylylated viral genome RNA. We sequenced the region containing the 5' proximal half of the F gene, and the subsequent HN and L genes, and predicted the complete amino acid sequence of the products of these genes. Sequence analyses confirmed that all the genes are flanked by consensus sequences and suggest that the viral mRNAs are capable of forming stem-and-loop structures. Comparison of the F and HN glycoproteins of Sendai virus with those of simian virus 5 strongly suggests that the cysteine residues are highly important for maintenance of the molecular structures of these glycoproteins.