Showing papers on "Gene expression published in 1980"
TL;DR: It is concluded that a control region within the gene directs RNA polymerase III to initiate transcription approximately 50 nucleotides upstream from the 5' border of this region.
544 citations
TL;DR: Results indicate that E. coli contains a set of genes that, like prophage lambda genes, are expressed in response to DNA-damaging agents and regulated by the recA and lexA gene products.
Abstract: Operon fusions in Escherichia coli were obtained that showed increased beta-galactosidase expression in response to treatment with the DNA-damaging agent mitomycin C. These fusions were generated by using the Mud(ApR, lac) vector [Casadaban, M.J. & Cohen, S.N. (1979) Proc. Natl. Acad. Sci. USA 76, 4530-4533] to insert the lactose structural genes randomly into the bacterial chromosome. Induction of beta-galactosidase in these strains, which carried fusions of lac to these din (damage-inducible) loci, was (i) triggered by UV light as well as by mitomycin C and (ii) abolished by either a recA- or a lexA- mutation. Similar characteristics of induction were observed when the lactose genes were fused to a prophage lambda promoter by using Mud(ApR, lac). These results indicate that E. coli contains a set of genes that, like prophage lambda genes, are expressed in response to DNA-damaging agents and regulated by the recA and lexA gene products. These din genes map at five bacterial loci. One din::Mud(ApR, lac) insertion results in a UV-sensitive phenotype and may be within the uvrA transcriptional unit.
502 citations
TL;DR: The results of these experiments indicate that the tK gene is not interrupted by intervening DNA sequences, and that certain oligonucleotide sequences adjacent to the termini of the tk gene are homologous to similarly positioned sequences common to structural genes of eukaryotic cells.
Abstract: This paper presents the nucleotide sequence of the Herpes Simplex Virus thymidine kinase (tk) gene. The position on the DNA sequence corresponding to the 5' and 3' termini of tk messenger RNA have been mapped. The mRNA termini are separated by slightly more than 1,300 nucleotides. The same 2,300 nucleotide segment of tk coding strand DNA is fully protected from S1 nuclease digestion when hybridized to tk mRNA. The location and size of the mRNA-coding segment corresponds to a region of the viral DNA that is essential for tk gene expression in microinjected frog oocytes. The nucleotide sequence of the HSV tk gene exhibits an open translational reading frame of 376 codons that extends from the methionine codon most proximal to the 5' terminus of tk mRNA to a UGA stop codon approximately 70 nucleotides from the poly-A addition site. The results of these experiments indicate that the tk gene is not interrupted by intervening DNA sequences, and that certain oligonucleotide sequences adjacent to the termini of the tk gene are homologous to similarly positioned sequences common to structural genes of eukaryotic cells.
479 citations
TL;DR: It is demonstrated, by analysing the RNAs made in ts K-infected cells after transfer from PT to the NPT, that this polypeptide's function is required continuously for synthesis of HSV-1 early andLate RNAs, thus identifying a control function essential for the expression of early and late HSV genetic information in eukaryotic cells.
Abstract: Controlled transcription of animal virus DNAs provides potentially useful models for elucidating the mechanisms which regulate eukaryotic gene expression. The progressive transcription of the herpes simplex virus type 1 (HSV-1) genome has been described previously1–3. Infection of permissive cells with HSV-1 in the presence of the protein synthesis inhibitor cycloheximide resulted in transcription of a restricted set of virus RNAs, referred to as the immediate early RNAs, which map within certain regions of the virus genome only3–5. Removal of cycloheximide led to the transcription of additional virus DNA sequences, which were expressed during the normal replicative cycle both at early and late times post-infection (before and after the onset of virus DNA replication, respectively) and which map throughout the virus genome3. Previously, we have described a temperature-sensitive mutant of HSV-1 Glasgow strain 17, ts K, which accumulated only the immediate early RNAs at the non-permissive temperature (NPT)5. Transfer of ts K-infected cells from NPT to the permissive temperature (PT), even in the absence of de novo protein synthesis, resulted in transcription of the DNA sequences expressed early and late post-infection5. This indicated the persistence at NPT of a non-functional immediate early polypeptide which on transfer to PT regained its function, required for progression from the immediate early to early stage of transcription. Here we demonstrate, by analysing the RNAs made in ts K-infected cells after transfer from PT to the NPT, that this polypeptide's function is required continuously for synthesis of HSV-1 early and late RNAs, thus identifying a control function essential for the expression of early and late HSV genetic information in eukaryotic cells.
408 citations
TL;DR: In mammalian cells, the rate of accumulation of several polypeptides, which were similar in size to the avian proteins, sharply increased after canavanine treatment.
Abstract: Four major acidic polypeptides, with molecular weights of 88, 72, 71, and 23 thousand, and minor polypeptides with molecular weights of 110, 50, 38, and 30 thousand rapidly accumulated in cultured chick embryo (CE) cells which were exposed for three hours to the arginine analogue canavanine. P110, P88, P71,72, and P23 had unique peptide maps. Evidence of a 27,000 dalton precursor to P23 was obtained. The analogue-stimulated proteins were not related to another set of inducible avian polypeptides known as the glucose-regulated proteins. In mammalian cells, the rate of accumulation of several polypeptides, which were similar in size to the avian proteins, sharply increased after canavanine treatment. Proteins with the same electrophoretic mobilities, isoelectric points, and peptide maps as the analogue-stimulated proteins were expressed at low levels in untreated cultures. To determine the time courses of the canavanine-mediated increases in protein accumulation and the recovery of protein metabolism after analogue treatment, radioactively labeled proteins were extracted from CE cells and analyzed on SDS-polyacrylamide gels. In cultures exposed to canavanine, the rates of accumulation of P88 and P71,72 increased from basal to new plateau levels in about 1.5 hours, while P23 required about 2.5 hours. When added with the analogue, actinomycin D and cordycepin blocked the increases in protein accumulation. These inhibitors also blocked the rapid decline in the rates of accumulation of the enhanced proteins which occurred after removal of canavanine. Studies of the matabolic stability of the enhanced proteins indicated that the changes in their accumulation were caused by alterations in their rates of synthesis. Thus, the analogue-mediated response fulfilled several of the criteria for inducible eucaryotic gene expression. The amino acid analogue p-fluorophenylalanine and the chain-terminating analogue of amino acyl-tRNA puromycin stimulated the synthesis of the same set of proteins induced by canavanine. The enhanced synthesis of these proteins appeared to be a cellular response to either the presence or catabolism of abnormal proteins and puromycyl peptides.
382 citations
TL;DR: It now appears that the various heat-shock genes can be, to a rather considerable extent, regulated independently of one another and the patterns of protein synthesis in heat-shocked cells are regulated by mechanisms which act at several different levels of gene expression.
326 citations
TL;DR: It was found that, in normal females, the genes for c36, c38, and at least one other chorion protein are specifically amplified more than 10-fold in the DNA of late-stage egg chambers, suggesting that altered gene dosage may be responsible for the decreased synthesis of chorions in the mutant.
Abstract: The endochorion and exochorion of Drosophila eggs are synthesized by the ovarian follicle cells during a brief period of about 5 hr. In this terminal phase of egg chamber development, the structural genes for several abundant chorion proteins are expressed at high levels according to a temporally regulated program. The female-sterile mutation ocelliless maps at the site of the genes for two of these proteins, the 36,000- and 38,000-dalton chorion proteins (c36 and c38), which are closely linked. The mutation results in a cis-acting reduction in the amounts of c36 and c38 that accumulate in late-stage egg chambers. We have investigated the mechanism that underlies this decreased production by using cDNA clones complementary to these gene sequences. Unexpectedly, it was found that, in normal females, the genes for c36, c38, and at least one other chorion protein are specifically amplified more than 10-fold in the DNA of late-stage egg chambers. The extra replication involves at least some adjacent chromosomal sequences and begins prior to the onset of mRNA and protein synthesis. The additional DNA remains stable after gene expression has ceased. The behavior of these genes is thus reminiscent of the properties of the DNA puffs that have been described in several groups of Diptera. The extent of amplification of c36 and c38, but not of the 18,000-dalton chorion protein c18 (which is unlinked), was decreased in the egg chambers of flies homozygous for ocelliless, suggesting that altered gene dosage may be responsible for the decreased synthesis of chorion proteins in the mutant.
260 citations
TL;DR: Measurements demonstrate that at least 11% of the single-copy DNA, or 60,000 diverse structural genes, are expressed in the entire plant during the dominant phase of its life cycle, suggesting that post-transcriptional selection mechanisms may play an important role in the regulation of plant gene expression.
253 citations
TL;DR: The regulation of thymidylate synthetase activity in mouse 3T6 fibroblasts during serum-induced transitions between the resting (G0) and growing state is described and indicates that the induction of gene expression was not directly coupled to DNA replication.
214 citations
TL;DR: It is shown that, in contrast to glucocorticoid-stimulated Zn2+ transport, the Zn 2+ and Dex induction of translatable MT-mRNA is independent of concomitant protein synthesis but not RNA synthesis; that is, MT induction by either agent is a primary induction response.
Abstract: Metallothioneins (MTs) are low molecular weight, heavy metal binding proteins unique in their high cysteine content and high affinity for Zn2+, Cd2+, Hg2+, Ag2+ and Cu2+ (refs 1–3). The synthesis of MTs is induced by zinc or cadmium in the liver and kidney4–8 and in cultured cells9–12. More recently MT induction by the steroid hormone dexamethasone (Dex) has been demonstrated in HeLa cells13 and adrenalectomized rats14. Because glucocorticoid hormones lead to an intracellular accumulation of zinc15–17, the question arises of whether the induction of MT gene expression by steroids is a ‘primary induction response’ (ref. 18), or due to elevated intracellular Zn2+. The glucocorticoid-induced transport of Zn2+ is dependent on concurrent protein synthesis10,19. We now show that, in contrast to glucocorticoid-stimulated Zn2+ transport, the Zn2+ and Dex induction of translatable MT-mRNA is independent of concomitant protein synthesis but not RNA synthesis; that is, MT induction by either agent is a primary induction response18.
166 citations
TL;DR: Preliminary Southern blot analysis of Eco RI restriction fragments of mouse embryo DNA revealed very complex patterns, suggesting that a family of homologous sequences for the individual rp-mRNAs may exist in the mouse genome.
TL;DR: This hereditary disease is shown to be the result of a deletion of at least 40,000 base pairs of the γδβ -globin gene locus, which results in a severe anaemia in newborns which subsequently develops into a β-thalassaemia syndrome in adult life.
Abstract: In gamma-beta-thalassaemia, human gamma- and beta-globin gene expression is suppressed; this results in a severe anaemia in newborns which subsequently develops into a beta-thalassaemia syndrome in adult life. This hereditary disease is now shown to be the result of a deletion of at least 40,000 base pairs of the gammadeltabeta-globin gene locus. The gamma- and delta-globin genes are deleted in the affected chromosome but, surprisingly, the beta-globin gene is still present, together with a large segment of the DNA sequences flanking the gene on its 5'-side and the entire region on the 3'-side of the gene. Hence, a deletion of DNA far from the beta-globin gene results in the suppression of its activity.
TL;DR: The chicken thymidine kinase gene is obtained as a 2.2-kilobase EcoRI/HindIII insert in pBR322 and transforms tk− animal cells with an efficiency equal to that of the cloned herpes simplex virus-1 tk gene.
Abstract: We have used the bacterial plasmid pBR322 as a vehicle to isolate genes coding for selectable markers from higher eukaryotes. In this way, we have obtained the chicken thymidine kinase (tk) gene as a 2.2-kilobase EcoRI/HindIII insert in BR322. The cloned gene transforms tk- animal cells with an efficiency equal to that of the cloned herpes simplex virus-1 tk gene.
TL;DR: These species presumably represent the subset of viral mRNAs that are "immediate early" products, requiring only host cell genes of their expression, and they do not include any of the conventionally recognized early m RNAs.
TL;DR: Attenuation and processing of the mRNA from the ribosomal protein-RNA polymerase operon rplJL--rpoBC have been demonstrated by the analysis of nuclease SI-resistant RNA .
Abstract: Attenuation and processing of the mRNA from the ribosomal protein-RNA polymerase operon rplJL--rpoBC have been demonstrated by the analysis of nuclease SI-resistant RNA . DNA hybrids. These hybrids were formed between RNA produced in vivo and specific DNA restriction fragments which span the rplL--rpoB intercistronic region. The 3' end of the predominant attenuated RNA lies 69 nucleotides beyond the end of the rplL gene following sequence features that are similar to those of other known attenuators. The nonattenuated transcript is normally cleaved in the intercistronic region. However, in an RNase III mutant strain, the hybrids corresponding to the cleaved nonattenuated mRNAs disappear and the expected full-sized hybrid is seen. We have localized the cleavage to an area of possible secondary structure in the transcript approximately 200 nucleotides beyond the end of the rplL gene. This demontrates RNase III processing of Escherichia coli mRNA. The methods used in this study permit the examination of specific ends of large and complex polycistronic mRNAs. Such experiments should help in understanding how posttranscriptional events influence gene expression.
01 Jan 1980
TL;DR: Organization of the Nuclear Genome.- Contrasting Patterns of DNA Sequence Organisation in Plants.- On the Evolution and Functional Significance of DNA sequence Organisation in Vascular Plants.
Abstract: Organization of the Nuclear Genome.- Contrasting Patterns of DNA Sequence Organisation in Plants.- On the Evolution and Functional Significance of DNA Sequence Organisation in Vascular Plants.- Plant DNA: Long, Pure and Simple.- The Evolution of Plant Genome Structure.- Cloning and Analysis of Plant DNA.- Chromosome and Gene Structure in Plants: A Picture Deduced from Analysis of Molecular Clones of Plant DNA.- A Model for a Molecular Cloning System in Higher Plants: Isolation of Plant Viral Promotors.- Transcription of the Nuclear Genome.- Purification, Structures and Functions of the Nuclear RNA Polymerases from Higher Plants.- RNA Polymerases and Transcription During Developmental Transitions in Soybean.- Nuclear Genome Expression.- Analysis and Resolution of mRNA Populations.- Structural Gene Expression in Tobacco.- The Regulation of Nuclear Genome Expression.- Messenger RNA Domains in the Embryogenesis and Germination of Cotton Cotyledons.- Hormonal and Genetic Regulation of ?-Amylase Synthesis in Barley Aleurone Cells.- Auxin-Regulated Cell Enlargement: Is there Action at the Level of Gene Expression?.- The Effects of Auxin on the Polyadenylated RNA of Soybean Hypocotyls.- The Role of Light in the Induction of mRNAs for Phenylalanine Ammonia-Lyase and Related Enzymes in Plant Cell Cultures.- Functional Characterization of some Ribosomal Proteins from Wheat Germ.- Macromolecular Properties, Biosynthesis and Genetic Regulation of Cereal Storage Proteins.- Maize Storage Proteins: Characterization and Biosynthesis.- Recent Evidence Concerning the Genetic Regulation of Zein Synthesis.- The Cloning of Zein Sequences and an Approach to Zein Genetics.- The Synthesis of Barley Storage Proteins.- Macromolecular Properties, Biosynthesis and Genetic Regulation of Legume Seed Storage Proteins.- Biosynthesis of Pea Seed Proteins: Evidence for Precursor Forms from in vivo and in vitro Studies.- Bean Seed Globulin mRNA: Translation, Characterization, and its Use as a Probe Towards Genetic Engineering of Crop Plants.- The mRNAs that Code for Soybean Seed Proteins.- Developmental Regulation of Seed Protein Synthesis in Seeds.- Organization and Expression of the Chloroplast Genome.- Organisation and Transcription of Maize Chloroplast Genes.- The Organisation in Higher Plants of the Genes Coding for Chloroplast Ribosomal RNA.- Transfer RNAs and Aminoacyl-tRNA Synthetases in Plant Organelles.- Synthesis, Transport and Assembly Of Chloroplast Proteins.- Synthesis, Transport and Assembly of Chloroplast Proteins.- In vitro Synthesis, Transport, and Assembly of the Constituent Polypeptides of the Light-Harvesting Chlorophyll a/b Protein Complex.- Synthesis, Processing and Functional Probing of P-32000, The Major Membrane Protein Translated Within the Chloroplast.- The Characterisation of Leaf Messenger RNAs and Their Use in the Synthesis of Complementary DNAs.- Sites of Synthesis and Codification of Chloroplast Elongation Factors.- Nuclear Genes Controlling Chloroplast Development.- Mitochondrial Genome Organization and Expression in Higher Plants.- Physico-Chemical and Restriction Endonuclease Analysis of Mitochondrial DNA from Higher Plants.- Mitochondrial Genome Expression in Higher Plants.- The Molecular Biology of Nitrogen Fixation.- Genetics of Nitrogen Fixation In The Bacterium Klebsiella Pneumoniae.- Expression of Host Genes During Symbiotic Nitrogen Fixation.- The Ti-Plasmid of Agrobacterium Tumefaciens.- The Ti-Plasmid of Agrobacterium tumefaciens its role in Crown-Gall Formation.- Location and Fate of pTi T37 DNA in Reversion of Crown Gall Teratoma.- Crown Gall Transcription of Ti Plasmid - Derived Sequences.- Crown Gall Specific Gene Products: Octopine and Nopaline Synthase.- Viral Genome Organization and Expression.- Structure of Plant Viral Genomes.- Translation of Plant Virus RNAs.- Expression of the Cauliflower Mosaic Virus Genome in Turnips (Brassica rapa).- Controlling Elements in Maize: Viroids.- A Re-examination of McClintock's "Controlling elements" in Maize in View of Recent Advances in Molecular Biology.- Structure and Function of Viroids.
TL;DR: It is concluded that the minus-strand polymerase regulates the rate of SFV plus- Strand RNA synthesis by determining the number of minus-Strand templates and that the synthesis of the minus -strand templates is regulated at the level of translation by a mechanism which utilizes one or more short-lived polymerase proteins.
Abstract: Semliki Forest virus (SFV)-infected BHK-21, Vero, and HeLa cells incorporated [3H]uridine into 42S and 26S plus-strand RNA and into viral minus-strand RNA (complementary to the 42S virion RNA) early in the infectious cycle. Between 3 and 4 h postinfection, the synthesis of minus-strand RNA ceased in these cultures, although the synthesis of plus-strand RNA continued at a maximal rate. At the time of cessation of minus-strand RNA synthesis, two changes in the pattern of viral protein synthesis were detected: a decrease in the translation of nonstructural proteins and an increase in the translation of the viral structural proteins. Addition of cycloheximide and puromycin to cultures of SFV-infected BHK cells actively synthesizing both viral plus- and minus-strand RNA resulted within 15 to 30 min in the selective shutoff of minus-strand RNA synthesis. Removal of the cycloheximide-containing medium led to the resumption of minus-strand synthesis and to an increased rate of viral RNA synthesis. We conclude that the minus-strand polymerase regulates the rate of SFV plus-strand RNA synthesis by determining the number of minus-strand templates and that the synthesis of the minus-strand templates is regulated at the level of translation by a mechanism which utilizes one or more short-lived polymerase proteins. Images
TL;DR: This chapter defines and discusses the mapping of adenovirus 2 nuclear transcription, which allows a relationship to be established between DNA structure, mRNA location, and definition of transcription units responsible for mRNA production.
Abstract: Publisher Summary This chapter defines and discusses the mapping of adenovirus 2 nuclear transcription. The immediate products of genes in mammalian cells are not used directly as mRNA but undergo extensive posttranscriptional modifications. At the level of transcription, the control of gene expression in mammalian cells may involve the posttranscriptional modifications. Therefore, any step concerned with processing of a nuclear precursor molecule can potentially be involved in the regulation of gene expression. Adenovirus-infected HeLa cells provide an ideal system for studying the formation of primary RNA transcripts. Adenovirus is an excellent model system for the study of the formation of primary transcripts because of the availability of highly refined physical maps of the adenovirus 2 genome that have been obtained using restriction endonucleases. This then allows a relationship to be established between DNA structure, mRNA location, and definition of transcription units responsible for mRNA production.
TL;DR: Changes in the intracellular concentration of cAMP act at the level of transcription to control gene expression during development, supported by the observation that several poly(A)+RNA sequences that normally accumulate after transcription of the discoidin I gene has ceased are synthesized prematurely in cells exposed to exogenous cAMP.
Abstract: The plasmid pDd812 contains the DNA copy of an mRNA sequence from Dictyostelium discoideum that undergoes first an increase and then a decrease in concentration during the first few hours of differentiation. We have recently shown that the mRNA sequence complementary to pDd812 encodes discoidin I, a developmentally regulated lectin that may play a role in cellular cohesion. By using pDd812 as a hybridization probe, we found that addition of cyclic AMP during the first few hours of development inhibited the accumulation of discoidin I mRNA. By measuring the rate of transcription in isolated nuclei, we showed that, at least in part, this inhibition results from a rapid and specific reduction in the rate of transcription of the discoidin I gene. Addition of cyclic AMP during the first few hours of development inhibited the accumulation of discoidin I mRNA. By measuring the rate of transcription in isolated nuclei, we showed that, at least in part, this inhibition results from a rapid and specific reduction in the rate of transcription of the discoidin I gene. Addition of cyclic AMP during the first few hours of development inhibited the accumulation of discoidin I mRNA. By measuring the rate of transcription in isolated nuclei, we showed that, at least in part, this inhibition results from a rapid and specific reduction in the rate of transcription of the discoidin I gene. Addition of high external concentrations of cAMP is known to increase the intracellular concentration to a level normally found later in development. This natural increase in cAMP concentration occurs at the time during development when transcription of the discoidin I gene ceases. We suggest, therefore, that changes in the intracellular concentration of cAMP act at the level of transcription to control gene expression during development. This hypothesis is supported by our observation that several poly(A)+RNA sequences that normally accumulate after transcription of the discoidin I gene has ceased are synthesized prematurely in cells exposed to exogenous cAMP.
TL;DR: It is concluded that the enzymatic mechanisms for the genesis of ASV mRNAs are widely distributed among vertebrates: in particular, phylogenetically disparate host cells may utilize the same signals within the ASV genome for the splicing and polyadenylation of viral RNA.
TL;DR: Deletion mutants of this plasmid are made, from which the major cap sites of SV40 early mRNAs have been removed along with some of the sequences upstream, and the deleted sequences appear to be dispensable for early gene expression.
Abstract: A recombinant plasmid was constructed by insertion of the early genes of simian virus 40 (SV40) into pBR322. When it was introduced into eukaryotic cells, the SV40 early genes were expressed. We have made deletion mutants of this plasmid, from which the major cap sites of SV40 early mRNAs have been removed along with some of the sequences upstream. The deleted sequences appear to be dispensable for early gene expression, but this does not necessarily imply that they serve no function in the initiation of transcription on wild-type SV40.
TL;DR: In this article, the authors measured the rates of fibroin mRNA synthesis in the posterior silk gland of Bombyx mori through the fourth feeding, fourth molting, and early fifth feeding stages.
TL;DR: In this paper, a kinetic hybridization analysis with cDNA probes revealed that a minor abundant class of sequences is markedly reduced in concentrations in the auxin-treated polyadenylated RNA.
TL;DR: Analysis of the RNA produced in abortively infected monkey cells indicated that the depressed synthesis of many of the late proteins can be ascribed to the reduced concentration of their corresponding mRNAs, which suggest a role for RNA splicing in the control of gene expression.
TL;DR: Nine temperature-sensitive mutations causing arrest of embryogenesis in Caenorhabditis elegans have been mapped and it is shown that seven genes, including emb-1 to emb-9, seem to be required exclusively for embryogenesis.
TL;DR: Although the precise mechanism of action of hydrocortisone is yet to be established, its modulation of prolactin action on casein gene expression appears to be via an effect at the posttranscriptional level.
Abstract: Publisher Summary This chapter discusses the complex mechanisms by which peptide and steroid hormones interact to regulate milk protein gene expression in the mammary gland at the transcriptional and posttranscriptional levels. Multi hormonal regulation of specific messenger RNA (mRNA) accumulation is characteristic of many hormonally responsive systems. For example, both prolactin and hydrocortisone are necessary for the maximal accumulation of casein mRNA in the mammary gland. The chapter reviews (a) casein mRNA isolation, characterization, and hormonal regulation in vivo; (b) steroid and peptide hormone actions in vitro; (c) mechanism of prolactin action; and (d) posttranslational modification of rat casein Although the precise mechanism of action of hydrocortisone is yet to be established, its modulation of prolactin action on casein gene expression appears to be via an effect at the posttranscriptional level. This is a unique example of a cooperative effect between a steroid and peptide hormone in regulating specific gene expression.
TL;DR: In Saccharomyces cerevisiae strains KL14-4A and 777-3A, four intervening sequences of 1900 (l alpha beta), 1400 (l beta gamma), 1300 (l gamma delta) and 650 bp (l delta epsilon) separate the five coding sequences (alpha-epsilon) of the structural gene (cob) for cytochrome b.
01 Jan 1980
TL;DR: This paper presents results of microinjection of Somatic Cells with Micropipettes and PEG-Erythrocyte Ghost Mediated Microinjection into Tissue Culture Cells, which successfully transferred DNA into Plant Cells with the Ti-Plasmid as a Vector and Expression of Messenger RNAs into Xenopus Laevis Oocytes.
Abstract: Microinjection of Somatic Cells with Micropipettes.- 1. Microinjection of Somatic Cells with Micropipettes and PEG-Erythrocyte Ghost Mediated Microinjection.- 2. Microinjection of Cellular and Viral mRNAs.- 3. Expression of Rabbit Globin mRNA Injected into Fused HeLa Cells.- 4. Biological Activity of Simian Virus 40 DNA Fragments and T-Antigen Tested by Microinjection into Tissue Culture Cells.- 5. Aspects of Cell Architecture and Locomotion.- Ghost Mediated Microinjection and Transfer of Membrane Components.- 6. Red Cell-Mediated Microinjection Studies on Protein Degradation.- 7. Transfer of Functional Compoments into Plasma Membrane of Living Cells: A New Tool in Membrane Research.- Liposome Mediated Transfer.- 8. Liposomes as Macromolecular Carriers for the Introduction of RNA and DNA into Cells.- 9. Liposomes in Drug Targeting.- Fusion of Cell Fragments and Cell Hybrids.- 10. Fusion of Cell Fragments as a Method in Cell Genetics.- 11. B-Cell and Epstein-Barr Virus (EB) Associated Functions in Human Cells and Hybrids.- 12. Tumorigenicity, Actin Cables and Gene Expression in Mouse CLID x CHO Cell Hybrids.- DNA and Chromosome Mediated Gene Transfer.- 13. Gene Transfer in Eukaryotes.- 14. DNA Mediated Gene Transfer between Mammalian Cells.- 15. Transfer of DNA into Plant Cells with the Ti-Plasmid as a Vector.- Microinjection of Xenopus Oocytes.- 16. Expression of Messenger RNAs Injected into Xenopus Laevis Oocytes.- 17. Surrogate Genetics in the Frog Oocyte.- Transfer of Cell Constituents Into Plant Cells.- 18. Grafts and Transfer of Cell Constituents into the Giant Unicellular Alga Acetabularia.- Contributors.
TL;DR: A basic 37,000-dalton protein (P37), purified from yeast cells, interacts with yeast RNA polymerase B and drastically increases its specific activity and can be isolated by sedimentation through a glycerol gradient.
TL;DR: It seems highly likely that this cell-free system will have extensive applications in the area of analysis of gene expression, as the results obtained confirm the conclusions of others obtained by much more elaborate in vivo techniques.
Abstract: Heretofore the DNA-directed coupled transcription-translation system, most useful in gene expression analysis, has been limited to the use of circular or long linear DNAs. Linear DNAs are degraded in this system by an exonucleolytic activity that can be eliminated by making the synthetic extracts from a suitable recB mutant of Escherichia coli. Using these extracts, we have examined the gene expression of a variety of linear DNAs. In particular, the complex pattern of expression of ribosomal protein genes and RNA polymerase genes in the rpoBC-rplLJ region has been analyzed by comparing the protein products obtained when using lambda rifd18 DNA with the product obtained when using the same DNA segmented with various restriction enzymes. The results obtained confirm the conclusions of others obtained by much more elaborate in vivo techniques. It seems highly likely that this cell-free system will have extensive applications in the area of analysis of gene expression.