Fusion Glycoprotein Gene Research Articles

Anti-tumor Effects of Gene Therapy with GALV Membrane Fusion Glycoprotein in Lung Adenocarcinoma

This study examined the efficacy of gene therapy of lung adenocarcinoma using specifically controlled type I herpes simplex virus recombinant vector expressing Gibbon ape leukemia virus membrane fusion glycoprotein gene (GALV.fus). Recombinant HSV-I plasmid carrying target transgene was constructed, and recombinant viral vector was generated in Vero cells using Lipofectamine transfection. Viral vector was introduced into lung adenocarcinoma A549 cells or human fetal fibroblast HFL-I GNHu 5 cells, or inoculated into human lung adenocarcinoma xenografts in nude mice. The anti-tumor and cytotoxic effects of GALV-FMG, the transgene, were examined in these cell and animal models. Expression of GALV-FMG in xenographs achieved 100 % tumorigenicity. Recombinant HSV-I viral vector also exhibited significant tumor cell killing effect in vitro. Relative survival rates of tumor cells treated with GALV-FMG or control vectors were, respectively, 20 and 70 %. GALV.fus has a potent anti-tumor effect against lung cancer both in vitro and in vivo. This anti-tumor potential provides foundation for further studies with this vector.

Comparison of human respiratory syncytial virus A2 and 8/60 fusion glycoprotein gene sequences and mapping of sub‐group specific antibody epitopes

Comparison of human respiratory syncytial virus A2 and 8/60 fusion glycoprotein gene sequences and mapping of sub‐group specific antibody epitopes

Comparison of human respiratory syncytial virus A2 and 8/60 fusion glycoprotein gene sequences and mapping of sub-group specific antibody epitopes

The fusion glycoprotein, F, of human respiratory syncytial virus is a principal target of neutralising antibodies and an important protective immunogen. Among sub-group A strains of the virus the F gene is highly conserved. A comparison of F gene sequences of two sub-group B strains, 8/60 and 18537, indicates that the gene also is conserved within this sub-group. However, both limited sequence variability and antigenic variation occurs between F genes from different virus sub-groups. Such variability may be important in the failure of natural- and vaccine-induced immunity and it is thus important to identify the variable epitopes. Three anti-F MAbs exhibiting sub-group specific neutralisation and binding to recombinant F glycoprotein were studied. Comparison of A2 and 8/60 F gene sequences revealed 64 predicted variant amino acids. In order to map the variant amino acids responsible for sub-group specific binding, three sets of chimaeric genes, in which different domains of A2 and 8/60 F were exchanged, were created and expressed. Sub-group specificity mapped to the N-terminal region of F1 for two MAbs (RS2B8 and RS348) and to the C-terminal region for the third. By using site-directed mutagenesis, sub-group specific binding of MAbs RS2B8 and RS348 was attributed to a predicted loop region between residues 200 and 216. This loop carried four residues variant between the sub-groups. Change of at least two was necessary to abrogate MAb binding.

Molecular cloning and sequence analysis of the fusion glycoprotein gene of human parainfluenza virus type 2

A cDNA clone containing a 2.0-kb insert was identified as the human parainfluenza virus type 2 (PI2) fusion glycoprotein gene by hybridizing with a viral RNA probe and a synthetic oligonucleotide derived from a conserved sequence found in other paramyxovirus fusion protein genes. The complete nucleotide sequence of the glycoprotein gene was determined by the dideoxynucleotide sequencing procedure and found to contain a single, large open reading frame encoding a protein of 551 amino acids with a calculated molecular weight of 59,664. Comparison of the P12 fusion protein with those of other paramyxoviruses indicated similarities in overall length, N-terminal signal peptide sequence (amino acids 7 to 25), C-terminal membrane-spanning region (amino acids 486 to 513), and a highly conserved fusion sequence region at the N-terminus of the F, subunit (amino acids 107 to 132).

Newcastle disease virus evolution: II. Lack of gene recombination in generating virulent and avirulent strains

Sequence analysis and comparison of the fusion glycoprotein genes of 11 Newcastle disease virus (NDV) isolates indicated a high degree of functional and structural constraint exerted on the change of the glycoprotein. However, synonymous nucleotide substitutions occurred frequently throughout the coding region. Facilitated by an analysis of synonymous difference ( K s ) in pairwise strain comparison, we defined the branching orders of the strains and identified three distinct evolutionary lineages correlating with the virulence as expressed by mean death time (MDT) for chick embryo. The typically virulent strains with MDT of about 50 hr were associated with one lineage, while the typically nonvirulent strains with MDT of infinity were of another lineage. The third lineage consisted of both virulent and avirulent strains whose MDTs lay on a continuum from 50 to 120 hr. Synonymous substitutions were found to occur with almost the same rates in the adjacent hemagglutinin-neuraminidase and membrane protein genes as in the fusion protein gene, and the branching orders based upon the K s for these genes were essentially identical to those derived from the fusion protein gene. Therefore, no gene exchange by recombination seems to have occurred to generate the strains of distinct lineages. Rather, the different strains appear to have evolved through various degrees of accumulation of point mutations. Besides these evolutionary features, the present study strongly supports the importance of the previously identified signals for gene expression and for the proteolytic activation of the gene product.

Nucleotide Sequence of the Coding and Flanking Regions of the Human Parainfluenza Virus Type 3 Fusion Glycoprotein Gene

Microbiology Society journals contain high-quality research papers and topical review articles. We are a not-for-profit publisher and we support and invest in the microbiology community, to the benefit of everyone. This supports our principal goal to develop, expand and strengthen the networks available to our members so that they can generate new knowledge about microbes and ensure that it is shared with other communities.

Nucleotide sequence of the coding and flanking regions of the human parainfluenza virus type 3 fusion glycoprotein gene.

The complete nucleotide sequence of the human parainfluenza virus type 3 (HPIV3) fusion (F) protein gene has been determined. The HPIV3 F gene is 1851 nucleotides long including six U residues in the genomic RNA, which probably direct synthesis of the first few nucleotides in the F mRNA polyadenylate tail. The HPIV3 F gene contains a single long open reading frame coding for 539 amino acids. The predicted molecular weight of the unglycosylated precursor F0 protein was 60031. Four potential carbohydrate acceptor sites were identified. Comparison of the HPIV3 F protein sequence with the F gene sequences of two other paramyxoviruses, Sendai virus and simian virus 5, indicated a very close evolutionary relationship between HPIV3 and Sendai virus. Sequence analysis of HPIV3 F gene flanking regions identified signals which appear to be responsible for polymerase recognition and polyadenylation.