Biomedical subjects

L L Domier

Publications and source records attributed to L L Domier.

23 records · Page 2Linked to original sources

PubMed1989

Infectious in vitro transcripts from cloned cDNA of a potyvirus, tobacco vein mottling virus.

Full-length cDNA copies of tobacco vein mottling virus (TVMV) RNA were constructed downstream from bacteriophage T7 or T3 RNA polymerase promoters. The plasmids were designed to produce in vitro transcripts containing, respectively, one or two guanosine residues at the 5' terminus not derived from the TVMV sequence and a single cytidine residue at the 3' terminus following the poly(A) tail. Introduction of transcripts from either plasmid into tobacco mesophyll protoplasts resulted in the accumulation of TVMV coat protein and RNA. Neither coat protein nor viral RNA accumulated in protoplasts inoculated with linearized cDNA or with in vitro transcripts synthesized in the absence of 7-methylguanosine(5')triphospho(5')guanosine (m7GpppG). Tobacco seedlings inoculated with native TVMV RNA developed symptoms a few days before those inoculated with in vitro transcripts; however, 3 weeks after inoculation, the symptoms produced by the two inocula were indistinguishable.

Blotting, Western↗

PubMed1989

Expression in transgenic plants of a viral gene product that mediates insect transmission of potyviruses.

Helper component (HC) is a virus-encoded nonstructural protein that is required for transmission of potyviruses by their aphid vectors. As a prelude to studies on the molecular basis of HC activity, a cDNA clone (pPB-3) was constructed that contained the first three cistrons (34 kDa-HC-42 kDa) of the RNA genome of the potyvirus tobacco vein mottling virus, the first six nucleotides of the adjacent cylindrical inclusion body protein cistron, and a synthetic translation termination codon. This construction was introduced into tobacco cells via a Ti plasmid-based vector. Northern blot analysis of transgenic plants demonstrated the presence of an RNA of the size expected from the construction of pPB-3, and Western blot analysis revealed the presence of a protein that comigrated with authentic HC, indicating that the proteolytic activity necessary to produce mature-sized HC was encoded by pPB-3. The HC produced in the transgenic plants was demonstrated to be active in a virus transmission bioassay with aphids.

Animals↗

PubMed1987

Amino acid sequence of the mRNA cap-binding protein from human tissues.

The 25-kDa mRNA cap-binding protein (CBP) involved in translation was purified by affinity chromatography from human erythrocytes and rabbit reticulocytes. The sequences of eight human and seven rabbit tryptic and V8 proteolytic peptides were determined. Based on the peptide sequence data, oligodeoxynucleotide probes were synthesized and used to screen human fibroblast and lymphocyte lambda cDNA libraries. The DNA sequence obtained from recombinant lambda phage inserts was found to code for all but one peptide. A 23-base oligonucleotide was synthesized based on the DNA sequence and used to prime synthesis of cDNA from human placental mRNA to construct a third library in lambda gt10. Screening with a 22-base oligonucleotide, whose sequence was upstream from the 23-base primer, yielded numerous recombinant phages with approximately equal to 250-base inserts. The 1900-base-pair cDNA sequence compiled from all phage inserts appeared to represent the entire primary sequence of CBP (Mr 25,117). Blot analysis of human placental and HeLa mRNA revealed multiple CBP mRNA species ranging from 1925 to 2250 bases. The amino acid sequence of CBP showed homology to the cap-binding PB2 protein of influenza virus.

Amino Acid Sequence↗

PubMed1986

The nucleotide sequence of tobacco vein mottling virus RNA.

The nucleotide sequence of the RNA of tobacco vein mottling virus, a member of the potyvirus group, was determined. The RNA was found to be 9471 residues in length, excluding a 3'-terminal poly(A) tail. The first three AUG codons from the 5'-terminus were followed by in-frame termination codons. The fourth, at position 206, was the beginning of an open reading frame of 9015 residues which could encode a polyprotein of 340 kDa. No other long open reading frames were present in the sequence or its complement. This AUG was present in the sequence AGGCCAUG, which is similar to the consensus initiation sequence shared by most eukaryotic mRNAs. The chemically-determined amino acid compositions of the helper component and coat proteins were similar to those predicted from the nucleotide sequence. Amino acid sequencing of coat protein from which an amino-terminal peptide had been removed allowed exact location of the coat protein cistron. A consensus sequence of V-(R or K)-F-Q was found on the N-terminal sides of proposed cleavage sites for proteolytic processing of the polyprotein.

Base Sequence↗

PubMed1986

Drosophila virilis histone gene clusters lacking H1 coding segments.

Approximately 30-40% of Drosophila virilis DNA complementary to cloned Drosophila histone genes is reduced to 3.4-kilobase-pair (kbp) segments by Bgl I or Bgl II digestion. The core histone genes of a 3.4-kbp Bgl II segment cloned in the plasmid pDv3/3.4 have the same order as the D. melanogaster core histone genes in the plasmid cDm500: H2B H3 H4 H2A. Nonetheless, pDv3/3.4 and cDm500 have different histone gene configurations: In pDv3/3.4, the region between the H2B and H3 genes contains 0.35 kbp and cannot encode histone H1; in cDm500, the region contains 2.0 kbp and encodes histone H1. The lack of an H1 gene between the H2B and H3 genes in 30-40% of D. virilis histone gene clusters suggests that changes in histone gene arrays have occurred during the evolution of Drosophila. The ancestors of modern Drosophila may have possessed multiple varieties of histone gene clusters, which were subsequently lost differentially in the virilis and melanogaster lineages. Alternatively, they may have possessed a single variety, which was rearranged during evolution. The H1 genes of D. virilis and D. melanogaster did not cross-hybridize in vitro under conditions that maintain stable duplexes between DNAs that are 75% homologous. Consequently, D. virilis H1 genes could not be visualized by hybridization to an H1-specific probe and thus remain unidentified. Our observations suggest that the coding segments in the H1 genes of D. virilis and D. melanogaster are greater than 25% divergent.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗