Regulation of the Synthesis of Ribulose-l,5-bisphosphate Carboxylase and Its Subunits in the Flagellate Chlorogonium elongatum. II. Coordinated Synthesis of the Large and Small Subunits

Abstract Transfer of heterotrophically grown cells of the unicellular green alga Chlorogonium elongatum to autotrophic growth conditions causes a 10 -15 fold increase in the amount of the chloroplastic enzyme ribulose-1,5-bisphosphate carboxylase. This increase was found to be due to de novo synthesis. The relative proportions of large and small subunits of the enzyme do not change. Their ratio is close to 3.4, the proportions in weight of the two subunits in the holoenzyme. Continous labelling with [35S]sulfate reveals that the ratios of incorporation into large and small subunits are essentially the same in autotrophic and heterotrophic cells. Pulse-chase experiments show that the subunits are degraded synchronously. The coordinated subunit synthesis cannot be uncoupled using inhibitors of protein and RNA synthesis or high temperature of cultivation of the alga. The results suggests a very tightly coordinated synthesis of the large and small subunits of ribulosebisphosphate carboxylase.

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Cytokinin-induced decrease in ribonuclease activity and initiation of gametophore buds in the protonema of mosses

Acta Societatis Botanicorum Poloniae ◽

10.5586/asbp.1976.028 ◽

2015 ◽

Vol 45 (3) ◽

pp. 327-334

Author(s):

Michał Spychała ◽

Irena Kocz-Zajchert ◽

Alicja Szwejkowska

Keyword(s):

Enzyme Activity ◽

Rna Synthesis ◽

De Novo ◽

Ribonuclease Activity ◽

Rnase Activity ◽

De Novo Synthesis ◽

Allosteric Inhibition ◽

Morphogenetic Effect ◽

Bud Induction ◽

Protein And Rna Synthesis

As early as after 4 hours of kinetin treatment a decrease in RNase activity was found in the moss protonema and it was maintained to at least 10 hours. It was shown that this decrease was correlated with the morphogenetic effect of kinetin (bud induction). No allosteric inhibition of RNase toy kinetin could be found. The decrease in enzyme activity was more pronounced When additionally inhibitors of protein and RNA synthesis were used. It is concluded that kinetin affects the RNase rather by an inhibition of de novo synthesis of the enzyme than by an increase of its decomposition by proteases.

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Physiology of Oil Seeds. V. Germination of NC-13 Virginia-type Peanut Seeds in the Presence of Inhibitors and Ethylene.1,2

Peanut Science ◽

10.3146/i0095-3679-2-2-9 ◽

1975 ◽

Vol 2 (2) ◽

pp. 73-77

Author(s):

D. L. Ketring

Keyword(s):

Amino Acids ◽

Protein Synthesis ◽

Total Protein ◽

Rna Synthesis ◽

De Novo ◽

Acid Synthesis ◽

De Novo Synthesis ◽

Tracer Studies ◽

Oil Seeds ◽

Protein And Rna Synthesis

Abstract Control dormant seeds that imbibed water for 16 hr germinated 100% after 10 μ 1/1 C2H4 was applied for 24 hr. Dormant seeds that imbibed cycloheximide (100 μg/ml), 6-methylpurine (50 μ g/ml) and 6-azauracil (50 μ g/ml) for 16 hr did not germinate at either 24 or 48 hr after 10 μ 1/1 ethylene treatment. Both protein- and nucleic acid-synthesis ihhibitors prevented germination induced by ethylene in these dormant seeds. Imbibition of 20 μ M ABA by dormant seeds prevented germination, but this effect was reversed by ethylene. Tracer studies with 14C-amino acids indicate that ABA does not inhibit total protein synthesis, but it does inhibit emergence in the absence of ethylene. In the presence of ABA plus ethylene, emergence occurred, but no change in total protein synthesis was detected. At 8 weeks after harvest, both germination and incorporation of 2–14C-uracil into RNA were inhibited by ABA and stimulated by ethylene. By 17 weeks after harvest, only the inhibition of germination and its reversal by ethylene were notable. However, at 17 weeks after harvest, ethylene enhanced RNA synthesis when germination and protein synthesis were inhibited by cycloheximide. Development of isocitritase activity in the seeds was inhibited by ABA and the inhibition was reversed by ethylene, indicating that de novo synthesis of protein is inhibited by ABA and activated by ethylene in these seeds. The opposite effects of ABA and ethylene on germination, RNA synthesis and isocitritase activity suggest that germination is controlled at the level of RNA and/or protein synthesis in these seeds. The prevention of germination of dormant seeds in the presence of ethylene by protein- and RNA-synthesis ihhibitors supports this suggestion, but the data do not preclude an action of ABA or ethylene prior to detectable affects on RNA or protein synthesis.

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Evidence for the De Novo Synthesis of Erythropoietin in Hypoxic Rats

Blood ◽

10.1182/blood.v40.5.662.662 ◽

1972 ◽

Vol 40 (5) ◽

pp. 662-670 ◽

Cited By ~ 35

Author(s):

J. C. Schooley ◽

L. J. Mahlmann

Keyword(s):

Rna Synthesis ◽

Actinomycin D ◽

De Novo ◽

Protein S ◽

Male Rats ◽

Hypoxic Exposure ◽

De Novo Synthesis ◽

Serum Erythropoietin

Abstract Significant increases in the serum erythropoietin of male rats occur after the end of a brief hypoxic exposure. These increases in the hormone are almost completely abolished when the kidneys are removed after the hypoxic exposure. Injection of puromycin or cycloheximide after the hypoxic exposure significantly decreases the subsequent increases in serum erythropoietin titers, whereas injections of actinomycin D at this time have no significant effect on erythropoietin levels. Injections of actinomycin D before the hypoxic exposure prevent the increase in serum erythropoietin that normally occurs. These findings suggest that a brief period of hypoxia initiates a DNA-dependent RNA synthesis that regulates the de novo ribosomal synthesis of protein(s) involved in the biogenesis of erythropoietin and that the kidney is essential for these reactions to occur.

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Enhancing Terminal Deoxynucleotidyl Transferase Activity on Substrates with 3′ Terminal Structures for Enzymatic De Novo DNA Synthesis

Genes ◽

10.3390/genes11010102 ◽

2020 ◽

Vol 11 (1) ◽

pp. 102 ◽

Cited By ~ 6

Author(s):

Sebastian Barthel ◽

Sebastian Palluk ◽

Nathan J. Hillson ◽

Jay D. Keasling ◽

Daniel H. Arlow

Keyword(s):

Elevated Temperatures ◽

De Novo ◽

Fold Increase ◽

Terminal Deoxynucleotidyl Transferase ◽

Synthesis Methods ◽

Transferase Activity ◽

Oligonucleotide Synthesis ◽

De Novo Synthesis ◽

Aqueous Conditions ◽

Terminal Structure

Enzymatic oligonucleotide synthesis methods based on the template-independent polymerase terminal deoxynucleotidyl transferase (TdT) promise to enable the de novo synthesis of long oligonucleotides under mild, aqueous conditions. Intermediates with a 3′ terminal structure (hairpins) will inevitably arise during synthesis, but TdT has poor activity on these structured substrates, limiting its usefulness for oligonucleotide synthesis. Here, we described two parallel efforts to improve the activity of TdT on hairpins: (1) optimization of the concentrations of the divalent cation cofactors and (2) engineering TdT for enhanced thermostability, enabling reactions at elevated temperatures. By combining both of these improvements, we obtained a ~10-fold increase in the elongation rate of a guanine-cytosine hairpin.

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EFFECTS OF CYTOSINE ARABINOSIDE ON DIFFERENTIAL GENE EXPRESSION IN EMBRYONIC NEURAL RETINA

The Journal of Cell Biology ◽

10.1083/jcb.61.3.688 ◽

1974 ◽

Vol 61 (3) ◽

pp. 688-700 ◽

Cited By ~ 13

Author(s):

R. E. Jones ◽

A. A. Moscona

Keyword(s):

Cytosine Arabinoside ◽

Rna Synthesis ◽

Actinomycin D ◽

De Novo ◽

Neural Retina ◽

Regulatory Genes ◽

De Novo Synthesis ◽

Macromolecular Synthesis ◽

Differential Gene ◽

Inhibition Of Dna Synthesis

The analogue of cytidine, cytosine arabinoside (Ara-C), elicited a significant increase in the level of glutamine synthetase (GS) in embryonic chick neural retina in the absence of the steroid inducer of the enzyme. The increase was due to de novo synthesis of GS and was mediated by RNA which accumulated in the presence of the effective concentration of Ara-C. Accumulation of GS did not result from the inhibition of DNA synthesis for which Ara-C is best known. This new effect of Ara-C involves differential suppression of macromolecular synthesis in this system: the concentration of Ara-C which caused maximum GS accumulation suppressed overall protein and RNA syntheses 65–75% without inhibiting the transcription and translation of templates essential for GS synthesis. Withdrawal of Ara-C resulted in restoration of RNA synthesis and cessation of GS accumulation, even though preformed templates for the enzyme were present; however, if all RNA synthesis was arrested with actinomycin D at the time of Ara-C withdrawal, GS continued to accumulate. The results are consistent with the hypothesis that Ara-C differentially affects the activity of structural and regulatory genes involved in the regulation of GS levels in the retina: Ara-C allows transcription of the enzyme-specific templates, but reversibly inhibits the expression of regulatory genes which limit the accumulation of GS.

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Biotin and glucose metabolism

Canadian Journal of Biochemistry ◽

10.1139/o70-079 ◽

1970 ◽

Vol 48 (4) ◽

pp. 493-500 ◽

Cited By ~ 29

Author(s):

K. Dakshinamurti ◽

L. Tarrago-Litvak ◽

Ho Chong Hong

Keyword(s):

Protein Synthesis ◽

Glucose Metabolism ◽

Pyruvate Kinase ◽

Rna Synthesis ◽

De Novo ◽

Diabetic Rat ◽

Bifunctional Enzyme ◽

Protein And Rna Synthesis ◽

Rat Experiments ◽

De Novo Protein Synthesis

Biotin enhances liver glucokinase in the diabetic rat. Experiments using inhibitors of protein and RNA synthesis suggest that this is mediated through de novo protein synthesis. Biotin treatment also increases the activities of other key glycolytic kinases, phosphofructokinase and pyruvate kinase, but has no effect on a bifunctional enzyme like phosphohexose isomerase.

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Enhanced RNA and protein synthesis in adipose tissue of rats adapted to periodic hyperphagia

Canadian Journal of Physiology and Pharmacology ◽

10.1139/y68-140 ◽

1968 ◽

Vol 46 (6) ◽

pp. 903-906 ◽

Cited By ~ 2

Author(s):

L. Kazdová ◽

T. Braun ◽

P. Fábry ◽

R. Poledne

Keyword(s):

Protein Synthesis ◽

Adipose Tissue ◽

Rna Synthesis ◽

De Novo ◽

Specific Activity ◽

De Novo Synthesis ◽

Experimental Conditions ◽

Rna And Protein Synthesis ◽

Meal Feeding ◽

The Difference

RNA synthesis measured by the incorporation of orotic acid-6-14C into RNA was investigated in isolated adipose tissue of control rats and of rats adapted to periodic hyperphagia, evoked by meal-feeding (a single 2-h meal per day). Both groups were fasted for 22 h and subsequently fed a measured test meal for another 2 h. It was revealed that 2 and 4 h after feeding there was no significant change in comparison with values during fasting, whereas in tissue of meal-fed rats the specific activity of RNA gradually increased by 22% and 41% respectively. The difference between controls and meal-fed rats was even much more marked if the specific activity of RNA in fat cells, isolated after incubation of the tissue, was measured. A significantly greater response of meal-fed rats was found when protein synthesis and lipogenesis in adipose tissue were assessed under the same experimental conditions. The possibility is discussed that the enhanced RNA and protein synthesis in adipose tissue of meal-fed rats is associated with de novo synthesis of enzymes involved in adaptive hyperlipogenesis.

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Glycine Betaine Transport in the Obligate Halophilic Archaeon Methanohalophilus portucalensis

Journal of Bacteriology ◽

10.1128/jb.182.17.5020-5024.2000 ◽

2000 ◽

Vol 182 (17) ◽

pp. 5020-5024 ◽

Cited By ~ 25

Author(s):

Mei-Chin Lai ◽

Tong-Yung Hong ◽

Robert P. Gunsalus

Keyword(s):

Transport System ◽

Glycine Betaine ◽

De Novo ◽

Compatible Solutes ◽

Growth Conditions ◽

The Other ◽

De Novo Synthesis ◽

Atpase Inhibitor ◽

High Affinity ◽

Solute Uptake

ABSTRACT Transport of the osmoprotectant glycine betaine was investigated using the glycine betaine-synthesizing microbe Methanohalophilus portucalensis (strain FDF1), since solute uptake for this class of obligate halophilic methanogenic Archaea has not been examined. Betaine uptake followed a Michaelis-Menten relationship, with an observed Kt of 23 μM and aV max of 8 nmol per min per mg of protein. The transport system was highly specific for betaine: choline, proline, and dimethylglycine did not significantly compete for [14C]betaine uptake. The proton-conducting uncoupler 2,4-dinitrophenol and the ATPase inhibitorN,N-dicyclohexylcarbodiimide both inhibited glycine betaine uptake. Growth of cells in the presence of 500 μM betaine resulted in faster cell growth due to the suppression of the de novo synthesis of the other compatible solutes, α-glutamate, β-glutamine, and N ɛ-acetyl-β-lysine. These investigations demonstrate that this model halophilic methanogen,M. portucalensis strain FDF1, possesses a high-affinity and highly specific betaine transport system that allows it to accumulate this osmoprotectant from the environment in lieu of synthesizing this or other osmoprotectants under high-salt growth conditions.

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Role of β-arrestin1/ERK MAP kinase pathway in regulating adenosine A1 receptor desensitization and recovery

AJP Cell Physiology ◽

10.1152/ajpcell.00190.2009 ◽

2010 ◽

Vol 298 (1) ◽

pp. C56-C65 ◽

Cited By ~ 18

Author(s):

Sarvesh Jajoo ◽

Debashree Mukherjea ◽

Sunny Kumar ◽

Sandeep Sheth ◽

Tejbeer Kaur ◽

...

Keyword(s):

Plasma Membrane ◽

De Novo ◽

Fold Increase ◽

Nuclear Factor Κb ◽

Activator Protein 1 ◽

De Novo Synthesis ◽

Ductus Deferens ◽

A1 Receptor ◽

Interfering Rna

Exposure of cells to adenosine receptor (AR) agonists leads to receptor uncoupling from G proteins and downregulation of the A1AR. The receptor levels on the cell surface generally recover on withdrawal of the agonist, because of either translocation of the sequestered A1AR back to plasma membrane or de novo synthesis of A1AR. To examine the mechanism(s) underlying A1AR downregulation and recovery, we treated ductus deferens tumor (DDT1 MF-2) cells with the agonist R-phenylisopropyladenosine ( R-PIA) and showed a decrease in membrane A1AR levels by 24 h, which was associated with an unexpected 11-fold increase in A1AR mRNA. Acute exposure of these cells to R-PIA resulted in a rapid translocation of β-arrestin1 to the plasma membrane. Knockdown of β-arrestin1 by short interfering RNA (siRNA) blocked R-PIA-mediated downregulation of the A1AR, suppressed R-PIA-dependent ERK1/2 and activator protein-1 (AP-1) activity, and reduced the induction of A1AR mRNA. Withdrawal of the agonist after a 24-h exposure resulted in rapid recovery of plasma membrane A1AR. This was dependent on the de novo protein synthesis and on the activity of ERK1/2 but independent of β-arrestin1 and nuclear factor-κB. Together, these data suggest that exposure to A1AR agonist stimulates ERK1/2 activity via β-arrestin1, which subserves receptor uncoupling and downregulation, in addition to the induction of A1AR expression. We propose that such a pathway ensures both the termination of the agonist signal and recovery by priming the cell for rapid de novo synthesis of A1AR once the drug is terminated.

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