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D H Bishop

Publications and source records attributed to D H Bishop.

At least 91 records · Page 5Linked to original sources
PubMed1984

Localized conserved regions of the S RNA gene products of bunyaviruses are revealed by sequence analyses of the Simbu serogroup Aino virus.

The complete nucleotide sequence has been determined for the S RNA of Aino virus, a member of the Simbu serogroup (Bunyavirus genus, family Bunyaviridae). The S RNA is 850 nucleotides long (2.76 X 10(5) daltons) and in the viral complementary sequence has a short 5' non-coding region of 34 nucleotides and a more extensive 3' non-coding region of 117 nucleotides. The 3'-5' complementarity of the Aino S RNA is about 25 residues long, depending on the arrangement. The Aino sequence predicts that, like snowshoe hare (SSH) and La Crosse (LAC) bunyaviruses (Bishop, D.H.L., et al. (1982) Nucleic Acids Res., 10, 3703-3713; Akashi, H. and Bishop, D.H.L. (1983) J. Virol. 45, 1155-1158), there are two S coded gene products, a nucleoprotein N, and a non-structural protein, NSS, that are read from overlapping reading frames in the viral complementary sequence. The Aino N primary gene product is composed of 233 amino acids (26.2 X 10(3) daltons) and is 45% homologous in sequence with that of LAC virus. The NSS protein of Aino virus is composed of 91 amino acids (10.5 X 10(3) daltons) and is 35% homologous in sequence with the LAC NSS protein. Unlike those viruses there are no uridylate tracts longer than 4 residues in the 5' non-coding region of the S viral RNA that could function as a template for polyadenylation of Aino S mRNA species.

Amino Acid Sequence↗
PubMed1984

Sequencing studies of pichinde arenavirus S RNA indicate a novel coding strategy, an ambisense viral S RNA.

Analyses of the complete sequence of the 1.1 X 10(6)-dalton, small (S) RNA of the arenavirus Pichinde and virus-induced cellular RNA species have revealed that the viral nucleoprotein, N, is coded in a subgenomic, non-polyadenylated, virus-complementary mRNA corresponding to the 3' half of the viral RNA (Auperin et al., Virology 134:208-219, 1984). By contrast, a second S-coded product, presumably the viral glycoprotein precursor (GPC), is coded in a subgenomic, virus-sense mRNA corresponding to the 5' half of the RNA. Between the two genes is a unique RNA sequence that can be arranged in a hairpin configuration and may function as a transcription terminator for both genes. The term ambisense RNA is coined to describe this novel coding strategy of a viral RNA. The unique feature of the strategy is that the presumptive GPC mRNA and its translation product cannot be made until viral RNA replication has commenced. In addition, it allows the two subgenomic mRNA species to be regulated independently from each other or from other viral mRNA species. The implications of this strategy on possible mechanisms for the induction and maintenance of viral persistence, an important attribute of arenavirus infections, are discussed.

Arenaviridae↗
PubMed1983

Nonviral heterogeneous sequences are present at the 5' ends of one species of snowshoe hare bunyavirus S complementary RNA.

Analyses of the 5' ends of snowshoe hare bunyavirus plus sense S RNA species (including mRNA) recovered from infected cells have revealed two types of termini. These include ends that are essentially exact copies of the 3' end of the viral S RNA and others that are similar, but additionally have 13-14 nucleotide extensions that are heterogeneous in sequence. The former probably represent replicative plus sense RNA species, the latter mRNA species that have host cell derived primer sequences.

Animals↗
PubMed1983

The formation of arenaviruses that are genetically diploid.

Analyses of RNA extracted from preparations of arenaviruses indicate that the relative molar proportions of the genomic L and S RNA species are frequently far from equal. In order to investigate the genetic significance of this observation temperature-sensitive (ts) mutants of two lymphocytic choriomeningitis (LCM) virus strains (ARM and WE) have been recovered and categorized into recombination groups (Groups I and II). Fingerprint analyses of wild-type progeny viruses obtained from dual infections with ARM Group II and WE Group I ts viruses indicate that they have L/S RNA genotypes of WE/ARM. It is concluded that the ARM Group II ts viruses have mutations in their L RNA species and that the WE Group I ts viruses have mutations in their S RNA species. Correspondingly it is deduced that the ARM Group I ts viruses have S RNA mutations and the WE Group II ts viruses mutations in their L RNA species. Cells coinfected with certain WE Group I mutants, or an ARM Group I and certain WE Group I ts mutants, have also yielded wild-type viruses. Fingerprint analyses have shown that the wild-type viruses obtained from the latter crosses are diploid with respect to their S RNA species. On subsequent passage these wild-type viruses shed high proportions of ts mutants. We interpret the data to indicate that the original Group I ts mutants that yielded the diploid viruses have mutations in different S RNA gene products so that the progeny produce plaques at the nonpermissive temperature by gene product complementation. No wild-type recombinant viruses have been obtained from crosses involving Pichinde and LCM ts mutants.

Arenaviruses, New World↗
PubMed1983

Interference between bunyaviruses in Aedes triseriatus mosquitoes.

Inhibition of the replication of alternate California serogroup bunyaviruses in Aedes triseriatus mosquitoes has been observed for mosquitoes previously infected with La Crosse (LAC) virus. By contrast, prior infection of mosquitoes with LAC virus did not interfere significantly with the subsequent infection and replication of Guaroa bunyavirus (Bunyamwera serogroup), or heterologous viruses such as West Nile flavivirus, or vesicular stomatitis rhabdovirus.

Aedes↗
PubMed1983

Tick-borne viruses structurally similar to Orthomyxoviruses.

Members of the Orthomyxoviridae are characterized at the structural level as enveloped, negative sense, RNA viruses that bud from the outer plasma membranes of infected cells and have seven or eight species of single-stranded RNA. None of the three types of orthomyxoviruses (influenza A, B, C) has been shown to be transmitted by arthropods; rather, the viruses are transmitted directly or indirectly from one infected vertebrate to another. Analyses of the virion RNA species and polypeptides of the tick-borne Thogoto and Dhori viruses indicate that they have structural characteristics similar to accepted members of the Orthomyxoviridae. For example, the viruses have seven size classes of single-stranded RNA with 3' end consensus sequences of HOUCGUUG (or U or A) UUGUUC. . . . The viruses contain 54-56 X 10(3) Da nucleocapsid protein, an internal 28 X 10(3) Da putative matrix protein plus minor 85-90 X 10(3) Da proteins, and a major outer 65 X 10(3) Da glycoprotein. In addition to their sensitivity to actinomycin D and alpha-amanitin the viruses morphologically and morphogenetically resemble orthomyxoviruses.

Amanitins↗
PubMed1983

Bunyavirus nucleoprotein, N, and a non-structural protein, NSS, are coded by overlapping reading frames in the S RNA.

It has been shown previously, by sequence analysis of the S RNA segment of snowshoe hare (SSH) bunyavirus, that two overlapping open reading frames in the viral complementary sequence code for proteins with molecular weights of 26.8 X 10(3) and 10.5 X 10(3) respectively. In addition to the viral nucleocapsid (N) protein, which is coded by the S RNA, analyses of parental and reassortant bunyavirus-infected cell extracts have shown that the viral S RNA and M RNA species each code for non-structural proteins (NSS and NSM, respectively). In the present report, in vitro translation analyses of the S mRNA species recovered from virus-infected cells indicate that a single size class of mRNA directs the synthesis of N and NSS. Compositional analyses of selected tryptic peptides of N and NSS have provided proof that N is the product of the first open reading frame, and NSS the product of the second.

Bunyaviridae↗
PubMed1983

Comparison of the sequences and coding of La Crosse and snowshoe hare bunyavirus S RNA species.

The sequence of the S RNA of La Crosse bunyavirus was deduced from analyses of DNA copies cloned in the Escherichia coli plasmid pBR322. The S RNA is 984 nucleotides in length, has a base ratio of 31.8% U, 27.0% A, 23.2% C, and 18.0% G, and codes for two distinct gene products that are read from overlapping reading frames in the viral complementary strand. The larger gene product (N, 26.5 x 10(3) daltons) contains 235 amino acids, and the smaller gene product (NSS, 10.4 x 10(3) daltons) has 92 amino acids. Comparisons with the published sequences of the related snowshoe hare bunyavirus S RNA and its gene products (Bishop et al., Nucleic Acids Res. 10:3703-3713, 1982) indicate that there are a total of 114 nucleotide differences (6 additions or deletions and 108 substitutions). Also, there are 22 amino acid differences between the N proteins and 12 amino acid differences between the NSS proteins of the two S RNAs.

Amino Acid Sequence↗
PubMed1983

Gene mapping in Pichinde virus: assignment of viral polypeptides to genomic L and S RNAs.

Previous studies have demonstrated that Pichinde virus encodes at least three primary translation products. Using wild-type Pichinde and Munchique viruses and a reassortant between the two, designated RE-2, we were able to assign polypeptides L, GPC, and NP to viral L and S RNAs. The RE-2 virus contains the L RNA of Pichinde virus and the S RNA of Munchique virus. Two-dimensional tryptic peptide mapping of L-[35S]methionine-containing peptides demonstrated that NP and GPC were identical in Munchique and RE-2 viruses, and both differed from the corresponding Pichinde virus tryptic profiles. On the basis of this, NP and GPC must be encoded by viral S RNA. Similar comparisons for L polypeptide demonstrated that L is a virus-specific polypeptide encoded by L RNA.

Arenaviridae↗
PubMed1983

Experimental infection of chipmunks and snowshoe hares with La Crosse and snowshoe hare viruses and four of their reassortants.

The infection of chipmunks (Tamias striatus), the vertebrate host of La Crosse (LAC) arbovirus, or snowshoe hares (Lepus americanus), the host of snowshoe hare (SSH) virus, was analyzed following subcutaneous inoculation with either LAC or SSH or certain LAC-SSH reassortant viruses. After inoculation, no adult hares or chipmunks developed signs of illness. Another reassortant, genotype LAC/LAC/SSH, has exhibited a marked inability to infect chipmunks and was avirulent for mice, probably because of a mutation in its L RNA segment. In chipmunks inoculated with reassortant viruses, neither the durations of viremias nor the maximum titers attained were demonstrably different from those found after inoculation with the parent LAC or SSH viruses. However, viruses with a SSH M RNA induced a higher viremia in snowshoe hares than viruses with a LAC M RNA. Also, the amount of virus needed to produce a detectable infection of chipmunks or hares was lower for viruses in which the M RNA came from the SSH parent than for those viruses having a LAC M RNA. Convalescent phase chipmunk and hare sera from animals infected with SSH virus or reassortant viruses having a SSH M RNA, neutralized parental SSH virus more effectively than did LAC virus. Conversely, the sera of animals infected with LAC virus or reassortants having a LAC M RNA, neutralized LAC virus more efficiently than did SSH virus.

Animals↗
PubMed1983

Bunyavirus gene structure - function relationships and potential for RNA segment reassortment in the vector: La Crosse and snowshoe hare reassortant viruses in mosquitoes.

Modern technology now permits the elucidation of viral gene contributions to virus-vector interactions. Such knowledge will undoubtedly permit determination of those mechanisms which function to preserve vector-borne virus disease cycle specificity and integrity in nature. In addition, the application of genetic techniques to reassortant virus generation in vectors should permit prediction of the evolutionary and epidemic potential of viruses in nature.

Aedes↗
PubMed1982

The complete sequence and coding content of snowshoe hare bunyavirus small (S) viral RNA species.

The complete sequence of the small (S) viral RNA species of snowshoe hare (SSH) bunyavirus has been determined, principally from a DNA copy of the RNA cloned in the E.coli plasmid pBr322. The viral S RNA (negative sense strand) is 982 nucleotides long (3.3 x 10(5) daltons) with complementary 5' and 3' end sequences. It has a base composition of 30.5%U, 25.8%A, 24.9%C and 18.7%G. In the viral complementary (plus sense) strand there are two overlapping open reading frames initiated by methionine codons. One reading frame codes for a 26.8 x 10(3) dalton protein, the other for a 10.5 x 10(3) dalton protein. The larger gene product is presumably related to the viral nucleoprotein (N) that is coded by the S RNA (Gentsch and Bishop (1978) J. Virol. 28, 417-419). The smaller gene product is probably related to the recently identified S RNA coded nonstructural protein (NSS) induced in virus infected cells (Fuller and Bishop (1982) J. Virol. 41, 643-648).

Amino Acid Sequence↗
PubMed1982

The complete sequence of RNA segment 2 of influenza A/NT/60/68 P1 protein.

A DNA copy of influenza A/NT/60/68 viral RNA segment 2, corresponding to protein P1, has been cloned in the E.coli plasmid pBr322. The clone is 2341 nucleotides long and represents a full-length copy of the viral RNA. In the viral complementary (plus sense) strand there is an open reading frame that is 2271 nucleotides long. The predicted primary gene product is a basic 86,300 dalton protein with a net charge at neutral pH of +23. A 29 amino acid stretch of the protein (coded by nucleotide residues 583-669) is highly basic and contains 7 lysine and 8 arginine residues. Other smaller clusters of basic amino acids are also present in the protein.

Amino Acid Sequence↗