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B Barrell

Publications and source records attributed to B Barrell.

25 records · Page 2Linked to original sources

Primary structure and transcription of the genes coding for the two virion phosphoproteins pp65 and pp71 of human cytomegalovirus.

Human cytomegalovirus contains a phosphorylated matrix protein of 65,000 apparent molecular weight (65K phosphoprotein; pp65) and a related phosphoprotein of 71,000 molecular weight (pp71). The 65K phosphoprotein is usually by far the most abundant structural component found in culture-grown purified virus particles. This study describes the precise mapping of the genes for both polypeptides, giving the entire nucleotide sequences and the exact positions of the respective transcripts. The 65K phosphoprotein is coded for by the 5'-terminal part of an abundant 4-kilobase (kb) mRNA. The 71K phosphoprotein corresponds to the single translational reading frame of a rare nonspliced 1.9-kb mRNA that is coterminal with the 4-kb transcript. The promoter for 4-kb mRNA appears to be unusual in structure; it does not contain a characteristic TATA sequence. The expression of antigenic epitopes from pp65 may allow improved serodiagnosis of human cytomegalovirus infections.

Amino Acid Sequence↗

Identification of the human cytomegalovirus glycoprotein B gene and induction of neutralizing antibodies via its expression in recombinant vaccinia virus.

A human cytomegalovirus (HCMV) glycoprotein gene with homology to glycoprotein B (gB) of herpes simplex virus and Epstein-Barr virus and gpII of varicella zoster virus has been identified by nucleotide sequencing. The gene has been expressed in recombinant vaccinia virus and the gene product recognized by monoclonal antibodies and human immune sera. Rabbits immunized with the recombinant vaccinia virus produced antibodies that immunoprecipitate gB from HCMV-infected cells and neutralize HCMV infectivity in vitro. These data demonstrate a role for this protein in future HCMV vaccines.

Amino Acid Sequence↗

Epstein-Barr virus genome may encode a protein showing significant amino acid and predicted secondary structure homology with glycoprotein B of herpes simplex virus 1.

We report significant sequence and predicted secondary structure homology between the herpes simplex virus 1 glycoprotein B (gB) and a protein predicted to be encoded by the BALF4 reading frame of Epstein-Barr virus (EBV). Homology was detectable at the DNA level and was highly significant at the protein level and when evolutionary substitution frequencies of amino acids in related proteins were taken into account. Hydropathic analyses predicted that the two proteins possess conserved N-terminal and C-terminal hydrophobic domains. The N-terminal hydrophobic domains share features in common with known cleavable membrane insertion signal sequences. The amino acid sequences of the C-terminal hydrophobic domains predict three adjacent membrane-spanning segments as had been previously predicted for gB. In an alignment of the two amino acid sequences, 247 of 903 gB residues had a matched pair in the BALF4 sequence, and 247 of 854 BALF4 residues were found to have a matched pair in the gB sequence. In addition, all 10 cysteine residues located outside the predicted signal sequence of both proteins were conserved, as were four predicted N-linked glycosylation sites. In all, 43% of the residues in the aligned sequences are predicted to possess equivalent secondary structures. gB is a virion envelope glycoprotein required for virus entry into cells. The domain of gB determining the rate of entry into cells has been mapped; the predicted structure of this domain in gB and the predicted EBV protein are almost identical. Similarly, the cytoplasmic domain of gB postulated to interact with submembrane proteins was also nearly identical in predicted structure to that of the EBV protein. These results suggest that EBV encodes a protein similar in structure and function to the herpes simplex virus 1 gB.

Amino Acid Sequence↗

Homology between two EBV early genes and HSV ribonucleotide reductase and 38K genes.

Computer-matching of amino acid sequences predicted from the complete EBV DNA sequence against the known HSV gene sequences has revealed significant homology between two EBV reading frames and the HSV1 and HSV2 140K and 38K proteins which are associated with ribonucleotide reductase activity. The two genes are arranged tandemly as in HSV though it appears that, unlike HSV, the two mRNAs are not 3' co-terminal. We have mapped two promoters predicted from the DNA sequence for these genes and shown them to be transcribed at a similar stage in the virus life cycle to that of the HSV genes.

Amino Acid Sequence↗

Strategies for the economic preparation of Epstein-Barr virus proteins of diagnostic and protective value by genetic engineering: a new approach based on segments of virus-encoded gene products.

Immunoprecipitation of Epstein-Barr viral proteins with various sera from normal adults, patients with fresh infectious mononucleosis or nasopharyngeal carcinoma was used to identify antigens which are of importance in the determination of immune status and characteristic of a particular disease. Some genes coding for of these antigens have been localized on the Epstein-Barr virus (EBV) genome by hybrid-selected translation. With the use of sequence data, these genes could then be subcloned from EBV DNA and expressed in eukaryotic and prokaryotic cells. Data on the expression are presented and the application of the methods described for the production of diagnostic reagents and vaccines is discussed.

Antibodies, Viral↗

Homologous upstream sequences near Epstein-Barr virus promoters.

The sequence of the 17,166-base-pair EcoRI C fragment of Epstein-Barr virus DNA, cell line B95-8, was determined. In vitro transcription was used to identify three RNA polymerase II promoters within this fragment of the virus. Cytoplasmic poly(A)+ RNAs starting at these points were demonstrated in B95-8 cells induced into virus production with 12-O-tetradecanoylphorbol 13-acetate. Uninduced B95-8 cells contained much less of these RNAs. The upstream sequences near the three promoters show striking homologies that may be involved in transcriptional control.

Base Sequence↗

Sequence analysis and in vitro transcription of portions of the Epstein-Barr virus genome.

The 17,180 base-pair Eco-RI-C fragment of Epstein-Barr virus has been sequenced in its entirety. This same fragment has also been analyzed for RNA polymerase II promoters, which are active in a soluble in vitro assay. These data are compared to the availability of predicted open reading frames and potential nucleotide signals associated with transcription. In addition, the DNA sequence of a number of previously undetected repeated DNA sequences from this and several nearby regions of the viral genome are reported.

Base Sequence↗