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S J Goebel

Publications and source records attributed to S J Goebel.

9 recordsLinked to original sources

An update on the vaccinia virus genome.

This communication is intended as a single source update of the initial report (Goebel et al., 1990a,b) which described the complete DNA sequence of the vaccinia virus genome. We have integrated published information as well as unpublished data. Our understanding of the complexities of the genetic functional organization of poxviruses is increasing at a remarkable rate. While some previously unknown identities have since been elucidated, the fact that the majority of vaccinia-encoded gene products still lack assigned functions lends excitement to the immediate future of poxvirus research.

Genes, Viral↗

Deletion of 55 open reading frames from the termini of vaccinia virus.

Each copy of the inverted terminal repeat of vaccinia virus consists of 8 kb of DNA containing 9 ORFS flanked near the terminus of the genome by 4 kb of repetitive DNA which in turn contains blocks of tandem repeats. Using plasmids containing repetitive DNA as the external arm, we have generated deletions at both the left and the right termini of the vaccinia genome. We report here the engineered deletion within a single vaccinia virus of 32.7 kb of DNA (including 38 ORFS) from the left terminus and 14.9 kb of DNA (including 17 ORFS) from the right terminus.

Base Sequence↗

Vaccinia virus encodes a protein with similarity to glutaredoxins.

Recently, we have reported the complete nucleotide sequence of vaccinia virus (Goebel, S. J., Johnson, G. P., Perkus, M. E., Davis, S. W., Winslow, J. P., and Paoletti, E. 1990, Virology 179, 247-266). Approximately 2.2 kbp leftward of the large subunit of ribonucleotide reductase resides a 108-amino acid open reading frame, O2L (nt 62,851-62,528) with significant similarity to known glutaredoxins. The deduced amino acid sequence of open reading frame O2L is 28.7% identical to the yeast and Escherichia coli proteins and greater than 40% identical to various mammalian glutaredoxins. Similar patterns of hydrophobicity as well as alpha-helix and beta-sheet potentials suggest that O2L and the glutaredoxins share a similar secondary structure. Furthermore, a common function is inferred by the presence of a highly conserved redox-active site.

Amino Acid Sequence↗

The complete DNA sequence of vaccinia virus.

The complete DNA sequence of the genome of vaccinia virus has been determined. The genome consisted of 191,636 bp with a base composition of 66.6% A + T. We have identified 198 "major" protein-coding regions and 65 overlapping "minor" regions, for a total of 263 potential genes. Genes encoded by the virus were located by examination of DNA sequence characteristics and compared with existing vaccinia virus mapping analyses, sequence data, and transcription data. These genes were found to be compactly organized along the genome with relatively few regions of noncoding sequences. Whereas several similarities to proteins of known function were discerned, the function of the majority of proteins encoded by these open reading frames is as yet undetermined.

Amino Acid Sequence↗

A DNA ligase gene in the Copenhagen strain of vaccinia virus is nonessential for viral replication and recombination.

Biochemical and genetic analyses have been conducted to determine whether a vaccinia virus open reading frame (orf) with extensive homology to the Saccharomyces cerevisiae DNA ligase gene encodes a functional ligase activity. This orf in HindIII A, designated A50R, is capable of encoding a 552-amino-acid, 63.4-kDa polypeptide. Full-length A50R mRNA produced in vitro directed the synthesis of a polypeptide with an apparent molecular weight of 57 kDa. Significantly, translation reactions programmed with A50R mRNA were capable of ligating a 3-kb Notl restriction fragment into multimers. DNA ligase activity was not detectable when either truncated sense or full-length antisense mRNA was translated in vitro. In extracts prepared from cells infected with wt vaccinia virus, DNA ligase activity was detected as assayed by the formation of a 57 kDa ligase-AMP adduct which was expressed early in the viral replication cycle. In cells infected with a DNA ligase deletion mutant no equivalent AMP-labeled adduct was detected. Relative to wt virus, the DNA ligase deletion mutant exhibited no significant differences in homologous recombination. These results indicate that the vaccinia orf A50R encodes a functional DNA ligase expressed early in infection, but this DNA ligase is nonessential for either recombination or viral replication.

Amino Acid Sequence↗

Vaccinia virus host range genes.

A gene encoding an 18-kDa polypeptide (ORF C7L) located in the vaccinia virus HindIII C fragment was shown to be functionally equivalent to previously described host range gene (ORF K1L) spanning the HindIII K/M fragment junction. Either C7L or K1L host range gene is necessary and sufficient by itself to allow replication of vaccinia virus on human cells. Deletion of both C7L and K1L genes from the wild-type vaccinia genome is required to derive a virus deficient for replication on human cells. Further, an ORF encoding a 77-kDa polypeptide derived from cowpox (CP77kDa) and previously shown to allow vaccinia to overcome the restriction for replication on Chinese hamster ovary cells could substitute for the vaccinia host range genes C7L and K1L in permitting replication of the virus on human cells. Additionally, the three unique host range genes C7L, K1L, and CP77kDa were functionally equivalent for vaccinia replication on pig kidney cells, but not on rabbit kidney cells.

Animals↗

Carcinoembryonic antigens: alternative splicing accounts for the multiple mRNAs that code for novel members of the carcinoembryonic antigen family.

The recent cloning of complete cDNAs encoding carcinoembryonic antigen (CEA) and non-specific cross-reacting antigen has revealed the existence of a new gene family belonging to the immunoglobulin gene superfamily. We have reported the isolation of a partial CEA cDNA and of L-cell transfectant cell lines that express human antigens cross-reactive with commercial antibodies directed to native CEA (Kamarck, M., J. Elting, J. Hart, S. Goebel, P. M. M. Rae, J. Nedwin, and T. Barnett. 1987. Proc. Natl. Acad. Sci. USA. 84:5350-5354). In this study, we describe the identification and cloning of 3.9-, 3.7-, 2.2-, and 1.8-kb cDNAs and a 23-kb genomic transcription unit, which code for new members of the CEA gene family. DNA sequence analysis of these cloned DNAs establishes the existence of a set of four alternatively spliced mRNAs which are expressed in several tumor cell lines, in human fetal liver, and in L-cell transfectants. Deduced amino acid sequences of the encoded isoantigens show extensive similarity to CEA and nonspecific cross-reacting antigens, but in addition demonstrate transmembrane and cytoplasmic domains. We designate members of this antigen family transmembrane CEAs. The transmembrane CEA isoantigens share general structural characteristics with members of the immunoglobulin gene superfamily and can be specifically compared to the cell adhesion molecules, N-CAM (neural cell adhesion molecule) and MAG (myelin-associated glycoprotein).

Amino Acid Sequence↗

Carcinoembryonic antigen family: characterization of cDNAs coding for NCA and CEA and suggestion of nonrandom sequence variation in their conserved loop-domains.

We have isolated cDNAs for carcinoembryonic antigen (CEA) and for a normal cross-reacting antigen (NCA) and report here their nucleotide and derived amino acid sequences. Our data show that both the CEA and NCA polypeptides are organized into extracellular domains, some with cysteine-linked loops, that share extensive sequence homology (approximately 78% overall) with each other and appear similar to immunoglobulin superfamily members. A major difference between the two apoproteins is the presence of a single loop-domain in NCA compared to three tandemly repeated loop-domains in CEA. Sequence comparisons between the extracellular domains of CEA and NCA show that the N-terminal and adjacent loop domains of each apoprotein have high homology (85-90%) to each other, while comparison of loop-domain regions reveals a possible nonrandom distribution of base changes and altered amino acids near certain cysteine residues that are inferred to be involved in forming disulfide loops. Both apoproteins show high identity in their hydrophobic C-termini that are reminiscent of the type of transmembrane tails seen in proteins that potentiate signal transduction. These findings, coupled with distinct expression profiles of CEA and NCA mRNAs, suggest that these apoproteins may function as unique cell-surface molecules mediating cell-specific interactions in normal and neoplastic cells.

Amino Acid Sequence↗

Carcinoembryonic antigen family: expression in a mouse L-cell transfectant and characterization of a partial cDNA in bacteriophage lambda gt11.

Genomic DNA and mRNA from the adenocarcinoma cell line LoVo were used to generate L-cell transfectants and a bacteriophage lambda gt11 cDNA clone that express epitopes of carcinoembryonic antigen (CEA). Primary and secondary L-cell transfectants expressing CEA were selected with a fluorescence-activated cell sorter (FACS). These transfectants, including some clones that were selected for high-level CEA expression by multiple rounds of FACS sorting, express a surface protein of 150 kDa that reacts with all anti-CEA antibodies tested. In parallel, a cDNA library of LoVo poly(A)+ RNA was constructed in lambda gt11 and fusion proteins were screened with polyclonal antisera against CEA. One positive clone, lambda cLV7, was identified that hybridized specifically to transfectant DNA. The nucleic acid sequence of the cDNA insert (cLV7) contained two regions of extensive internal homology, with greater than 70% identity at the amino acid level. cLV7 hybridized to three mRNA species of LoVo cells and to a predominant mRNA of the CEA-expressing transfectants. Hybridization of cLV7 to restriction endonuclease-digested genomic DNA of colon carcinoma cells, normal human cells, and human-mouse somatic cell hybrids revealed the presence of multiple hybridizing bands, one of which was present in transfectant cells. These CEA-related sequences are not rearranged in tumors and, by somatic cell hybrid analysis, were mapped to human chromosome 19.

Amino Acid Sequence↗