Showing papers on "Gene published in 1977"
TL;DR: The sequence identifies many of the features responsible for the production of the proteins of the nine known genes of the organism, including initiation and termination sites for the proteins and RNAs.
Abstract: A DNA sequence for the genome of bacteriophage phi X174 of approximately 5,375 nucleotides has been determined using the rapid and simple 'plus and minus' method. The sequence identifies many of the features responsible for the production of the proteins of the nine known genes of the organism, including initiation and termination sites for the proteins and RNAs. Two pairs of genes are coded by the same region of DNA using different reading frames.
2,023 citations
TL;DR: Recombinant bacterial plasmids have been constructed that contain complementary DNA prepared from rat islets of Langerhans messenger RNA that contain cloned sequences representing the complete coding region of rat proinsulin I, part of the preproinsulin II prepeptide, and the untranslated 3' terminal region of the mRNA.
Abstract: Recombinant bacterial plasmids have been constructed that contain complementary DNA prepared from rat islets of Langerhans messenger RNA. Three plasmids contain cloned sequences representing the complete coding region of rat proinsulin I, part of the preproinsulin I prepeptide, and the untranslated 3' terminal region of the mRNA. A fourth plasmid contains sequences derived from the A chain region of rat preproinsulin II.
1,135 citations
TL;DR: Findings imply a new mechanism for the biosynthesis of Ad2 mRNA in mammalian cells which is complementary to sequences within the Ad2 genome which are remote from the DNA from which the main coding sequence of each mRNA is transcribed.
1,091 citations
TL;DR: This work has reported the first synthesis of a functional polypeptide product from a gene of chemically synthesized origin, including the sequence of amino acids corresponding to somatostatin, in vitro.
Abstract: A gene for somatostatin, a mammalian peptide (14 amino acid residues) hormone, was synthesized by chemical methods. This gene was fused to the Escherichia coli beta-galactosidase gene on the plasmid pBR322. Transformation of E. coli with the chimeric plasmid DNA led to the synthesis of a polypeptide including the sequence of amino acids corresponding to somatostatin. In vitro, active somatostatin was specifically cleaved from the large chimeric protein by treatment with cyanogen bromide. This represents the first synthesis of a functional polypeptide product from a gene of chemically synthesized origin.
928 citations
TL;DR: Derivatives of phage λ are described for use as vectors for fragments of DNA generated with the HindIII and EcoRI restriction enzymes to permit the ready distinction between recombinant and vector phages by the colour of the plaques.
Abstract: Derivatives of phage lambda are described for use as vectors for fragments of DNA generated with the HindIII and EcoRI restriction enzymes. With some vectors, hybrid molecules are recognised by a change from a turbid to a clear plaque morphology resulting from the insertion of a fragment of DNA into the lambda gene coding for the phage regressor. Other vectors contain a central, replaceable fragment of DNA which imparts a readily recognisable phenotype. This central fragment may include either a gene for a mutant transfer RNA (suppressor) or a part of the lacZ gene of E. coli able to complement a lacZ host. The appropriate lacZ host and indicator plates permit the ready distinction between recombinant and vector phages by the colour of the plaques.
675 citations
TL;DR: A very limited number of discrete rabbit DNA fragments was found which could form well matched hybrids with PβG1 DNA, consistent with the presence of a single copy of the β-globin gene per haploid genome.
539 citations
TL;DR: The primary structure of DNA containing the sequence for rat pituitary growth hormone mRNA has been determined and the amino acid sequences for rat growth hormone and its precursor form have been deduced from the determined nucleotide sequences.
Abstract: The primary structure of DNA containing the sequence for rat pituitary growth hormone mRNA has been determined. DNA was obtained by reverse transcription of polyadenylated RNA from cultured pituitary cells and from recombinant bacterial plasmids. The amino acid sequences for rat growth hormone and its precursor form have been deduced from the determined nucleotide sequences.
509 citations
TL;DR: Schmeissner et al. as mentioned in this paper used a fine structure deletion map to construct a combined gene-protein map, in which deletion intervals on the genetic map are correlated with known segments of the protein sequence.
486 citations
TL;DR: The application of hybrid-arrested translation for the identification of structural gene sequences within recombinant DNA molecules and to locate and order precisely several adenovirus 2 polypeptides within the viral genome is demonstrated.
Abstract: We present a simple method for directly correlating structural gene sequences in DNA with their corresponding mRNAs. This is based upon the fact that mRNA hybridized with its complementary DNA will not direct the cell-free synthesis of a complete polypeptide. Full translational activity of the mRNA is recovered upon the heat melting of the hybrid. Utilizing the rabbit beta globin clone PbetaG1, we demonstrate the application of hybrid-arrested translation for the identification of structural gene sequences within recombinant DNA molecules. In addition, the method is used to locate and order precisely several adenovirus 2 polypeptides within the viral genome.
475 citations
TL;DR: This chapter discusses the structural, electrophysiological, biochemical and pharmacological properties of neuroblastoma-glioma cell hybrids in cell culture and the rescue of latent viruses and the genetic analysis of malignancy and of viral gene expression.
Abstract: Publisher Summary This chapter discusses the structural, electrophysiological, biochemical and pharmacological properties of neuroblastoma-glioma cell hybrids in cell culture. Hybrid cells are formed by the fusion of two different cell types. The cells fused may be as different as those of humans and of mosquitos, as similar as cells from two strains of mice, or only clearly different in one gene or in the kind of tissue of the same animal they were derived from. Hybrids are prepared by fusion, e.g., of a mutant hamster cell line and a wild-type human cell line. If one selects for wild-type cells, the segregation of human chromosomes will provide hybrid cells that retain a single human chromosome, or part of one, carrying the gene that complements the hamster cell to a wild-type cell. This and similar methods are also used for the analysis of gene linkage. Other important applications of cell hybrids are the rescue of latent viruses and the genetic analysis of malignancy and of viral gene expression.
382 citations
TL;DR: The faithful representation of β-globin mRNA in the PβG1 DNa insertion establishes the validity of using cloned DNA, initially derived from double-stranded DNA transcripts of mRNA, for studying the structure of eucaryotic genes.
TL;DR: The insert appears to be a general property of the rabbit β-globin gene, even in tissues in which this gene is active, which suggests that the insert is not involved in inactivating the gene in nonerythroid tissues.
TL;DR: The ovalbumin gene is split in chicken DNA and two interruptions in the sequences coding for ovalbumIn mRNA have been detected, at least one of them lying in the protein coding sequence.
Abstract: The ovalbumin gene is split in chicken DNA. Two interruptions in the sequences coding for ovalbumin mRNA have been detected, at least one of them lying in the protein coding sequence. The unexpected gene organisation is present both in oviduct cells highly specialised in ovalbumin synthesis and in erythrocytes.
TL;DR: It is shown that essentially all the G-A-T-C sequences are methylated in DNA from the pneumococcal strain that produces Dpn II as well as inDNA from Hemophilus influenzae and Escherichia coli and in the dam-3 mutant of E. coli.
TL;DR: Host-range mutants of adenovirus type 5 have been selected on human embryo kidney cells transformed by sheared adeno 5 DNA and these mutants grow well on 293 cells, but are restricted on HeLa cells.
TL;DR: It is proposed that an inversion of this region is the phase-determining event in flagellar gene expression in Salmonella.
Abstract: Flagellar antigens are specified by two genes, H1 and H2. The expression of these genes is regulated such that only one gene activity, or phase, is expressed at a given time. Molecular cloning techniques were used to isolate the segments of Salmonella DNA which contain these genetic loci. Heteroduplex analyses revealed an anomaly in the cloned fragment, that is, and apparent inversion, which was shown to be adjacent to the H2 gene. A correlation was demonstrated between the phase state of the H2 gene and the sequence of the adjacent segment. We propose that an inversion of this region is the phase-determining event in flagellar gene expression in Salmonella.
TL;DR: Using electron microscopic RNA loop mapping to determine, to within 200 nucleotides, the chromosome coordinates of the 5′ and 3′ ends of adenovirus type 2 transcripts isolated from the cytoplasm of productively infected human KB cells, the most frequent late RNA loop occurred between coordinates 51.9 and 62.8.
TL;DR: The 5S DNA of Xenopus laevis, coding for oocyte-type 5S RNA, consists of many copies of a tandemly repeated unit of about 700 base pairs, each unit contains a "pseudogene" in addition to the gene.
TL;DR: One of the eight endonuclease EcoRI fragments of yeast DNA that hybridize to yeast tRNATyr has been identified with the genetically defined nonsense-suppressor locus SUP4 by analyzing the meiotic linkage between the genetic determinant for the SUP4 phenotype and that for an electrophoretic variant of the EcoRI fragment.
Abstract: One of the eight endonuclease EcoRI fragments of yeast DNA that hybridize to yeast tRNATyr has been identified with the genetically defined nonsense-suppressor locus SUP4. This identification was achieved by analyzing the meiotic linkage between the genetic determinant for the SUP4 phenotype and that for an electrophoretic variant of the EcoRI fragment. The SUP4 gene was then cloned from an ochre-suppressing yeast strain and analyzed by DNA sequencing. A wild-type SUP4 gene and two other genetically unidentified tRNATyr genes were also sequenced. The sequence of the ochre suppressor differs from that of the wild-type genes by virtue of a G.C leads to T.A transversion in the base pair that codes for the wobble position base of the tRNATyr anticodon. All four genes contain, immediately to the 3' side of the anticodon triplet, a 14 base pair tract that is not present in mature tRNATyr. Although the four genes, which represent three unlinked chromosomal loci, all encode the same mature tRNA sequence, there is virtually no observable sequence homology between the three loci in the region preceding the 5' end of the mature tRNATyr sequences.
TL;DR: The complete results of the analysis of over 5300 independently derived nonsense mutations in the lacI gene are presented, which have been mapped and divided into specific sites to allow a detailed correlation of the physical and genetic map.
TL;DR: Transposable genetic elements in prokaryotes and eukaryotes, when inserted at a given locus, can control expression of the locus and cause large scale rearrangements of adjacent DNA sequences.
Abstract: Transposable genetic elements in prokaryotes and eukaryotes, when inserted at a given locus, can control expression of the locus and cause large scale rearrangements of adjacent DNA sequences. Striking similarities in genetic behaviour between the two groups of elements have led to the proposal of a molecular model of eukaryotic controlling elements, and to suggestions about the part such elements may play in evolution and differentiation.
TL;DR: It is apparent from these investigations that the two types of cRNA are synthesised by the same transcriptase but that the production of unpolyadenylated complete transcripts is dependent upon the synthesis of certain other viral protein(s).
TL;DR: Observations suggest that both mRNAs contain a long common sequence, complementary to at least two different sites on the Ad2 genome remote from the start of these two genes.
TL;DR: It appears that glucocorticoids regulate MMTV genes principally by this rapid and specific alteration of their rate of transcription, as shown in M1.19 rat hepatoma cells.
Abstract: Glucocorticoid hormones specifically increase the intracellular concentration of mouse mammary tumor virus (MMTV) RNA in a cultured cell line from a GR mouse mammary carcinoma (GR) and in an MMTV-infected rat hepatoma cell line (M1.19). In contrast, these steroids have no effect on the concentration of MMTV RNA in a lymphoma line, S49, from a Balb/c mouse. Using a molecular hybridization procedure to detect newly synthesized RNA, we have directly measured the effect of dexamethasone, a synthetic glucocorticoid, on the rate of MMTV RNA synthesis. In GR cells the hormone causes a 10-fold increase in the rate of synthesis of viral RNA without appreciably affecting the overall rate of cellular RNA synthesis. The transition from the basal to the maximally stimulated rate of MMTV RNA synthesis occurs within the earliest labeling period, 0-15 min after addition of the hormone. Thus, it appears that glucocorticoids regulate MMTV genes principally by this rapid and specific alteration of their rate of transcription. Similar results are obtained in M1.19 rat hepatoma cells. In contrast, dexamethasone does not affect the rate of viral RNA synthesis in S49 lymphoma cells.
TL;DR: Results demonstrate the existence of two initiation sites, S 1 and S 2, for transcription of the galactose operon of E. coli and suggest that when CRP or cAMP is absent, transcription starts from S 2 in vivo.
TL;DR: A model for viral gene expression is proposed which conforms to previous suggestions that eucaryotic cells initiate translations only at the 5′ termini of messenger RNAs.
TL;DR: The sequence arrangement of genes coding for stable rRNA species and of the interspersed spacers on long single strands of rDNA purified from total chromosomal DNA of Drosophila melanogaster has been determined by a study of the structure of rRNA:DNA hybrids.
TL;DR: This work presents evidence of extensive gene silencing in the 50-Myr history of a family of tetraploid fishes and suggests that those species regarded by systematists as advanced may have lost the expression of more duplicate genes than primitive species.
Abstract: INCREASES in cellular DNA content have been important in the evolution of eukaryotes1–3. One mechanism for increasing DNA content is polyploidisation, which has been observed in a wide variety of organisms4–8, and which is believed to have preceded the evolution of the early vertebrates9. It has been suggested that, following gene duplication, many of the redundant copies would be silenced early in evolution by mutation10,11. Those duplicate genes remaining expressed are then available to diverge in structure and acquire new functions9. We present evidence of extensive gene silencing in the 50-Myr history of a family of tetraploid fishes. Furthermore, those species regarded by systematists as advanced (that is, morphologically divergent from the ancestral form) may have lost the expression of more duplicate genes than primitive species (that is, those with a morphology similar to the ancestral form).
TL;DR: There is striking clustering of nucleotide residues that show homology between the assembly origin and the coat protein gene in those regions coding (in the coat gene) for conserved amino acids, although the protein sequences that may be translated from the two genes are dissimilar.