Regulation of accumulation of the major thylakoid polypeptides in Chlamydomonas reinhardtii y-1 at 25 degrees C and 38 degrees C.

The amount of messenger RNA (mRNA) for polypeptides of the chlorophyll a/b-protein complex of thylakoid membranes in etiolated and greening cells of Chlamydomonas reinhardtii y-1 was examined by immunoprecipitation and electrophoresis of products of in vitro translation to determine at which stage production of these polypeptides is regulated. Cells grown 4 d in the dark at 25 degrees C contained small amounts of translatable mRNA for the major membrane polypeptides. Exposure of these etiolated cells to light, under conditions in which the membrane polypeptides accumulated, resulted in a significant increase in the quantity of the mRNA. In contrast, when etiolated cells were incubated for 1-2 h in the dark at 38 degrees C, translation assays indicated that mRNA for the membrane polypeptides became abundant. Moreover, the quantity of the mRNA did not increase when these cells subsequently were exposed to light. Therefore, at 38 degrees C the cellular level of the polypeptides is not regulated by synthesis of mRNA. The in vitro synthesized polypeptides, which were precipitated with antibodies prepared against the purified thylakoid polypeptides, had apparent molecular weights of 31,500 and 30,000. The corresponding immunoprecipitated polypeptides made in vivo had apparent molecular weights of 29,500 and 26,000. Thus, the membrane polypeptides are made as precursors. No net accumulation of the polypeptides occurred in cells in the dark at 38 degrees C, but immunoreactive polypeptides the size of the mature membrane components were labeled during incubation of cells with [14C]acetate in the dark. These results indicated that the mRNA was translated in the dark, but since the polypeptides did not accumulate, the products of translation were probably degraded. We conclude from our experiments that at 25 degrees C production of the polypeptides is regulated by the level of translatable mRNA in the cells. At 38 degrees C, however, the accumulation of the polypeptides is controlled by posttranslational processes.

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Gene expression in Acetabularia. III. Comparison of stained cytosolic proteins and in vivo and in vitro translation products

Journal of Cell Science ◽

10.1242/jcs.60.1.1 ◽

1983 ◽

Vol 60 (1) ◽

pp. 1-12

Author(s):

R.L. Shoeman ◽

G. Neuhaus ◽

H.G. Schweiger

Keyword(s):

Messenger Rna ◽

In Vitro Translation ◽

Cytosolic Proteins ◽

Molecular Weights ◽

Translational Activity ◽

Stage Of Development ◽

Extended Analysis ◽

Species Specific

A comparison of stained cytosolic proteins, in vivo 80 S ribosome translation products and in vitro translation products of poly(A)+ RNA from three species of Acetabularia was performed after characterization of their molecular weights and isoelectric points via two-dimensional electrophoresis. A total of 803 stained proteins, and 121 in vivo and 77 in vitro translation products, representing the most abundant proteins in each category, were analysed. In interspecies comparisons, approximately 10% of the stained proteins were common to all three species and more than 50% were found to be species-specific. Approximately 25% of the in vivo translation products were common to all three species and more than 30% were found to be species-specific. The majority of the in vivo and in vitro translation products were detected by one or both of the other methods employed. Even though the analysis was limited to the most abundant proteins detected by each of the three methods and to one stage of development, the results suggest that the translation of some proteins is not regulated, that the in vivo translation of others, whose mRNA is present and translated in vitro, is turned off while the translation in vivo of others is enhanced relative to the total. This feature makes them candidates for stage-specific proteins. The results provide a firm basis for the extended analysis of the biological activity of heterologous messenger RNA in Acetabularia cytoplasm and for a more complete cataloguing of the mRNA population and translational activity at different stages in the development of Acetabularia.

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Production of multiple forms of glucoamylase in Aspergillus awamori

Biochemistry and Cell Biology ◽

10.1139/o87-099 ◽

1987 ◽

Vol 65 (8) ◽

pp. 762-765 ◽

Cited By ~ 3

Author(s):

Resham S. Bhella ◽

Illimar Altosaar

Keyword(s):

Molecular Weight ◽

Northern Blot Analysis ◽

De Novo ◽

In Vitro Translation ◽

Aspergillus Awamori ◽

Multiple Forms ◽

Molecular Weights ◽

Specific Mrnas

The biosynthesis of glucoamylases in Aspergillus awamori was studied by in vivo protein labelling and analysis of glucoamylase-specific mRNAs. Two types of glucoamylases with molecular weights of 100 000 and 82 000 were shown to be synthesized de novo. Deglycosylation of the 100 000 molecular weight glucoamylase type resulted in the formation of another glucoamylase form with molecular weight of about 94 000. De novo synthesis of two types of glucoamylases was further confirmed by the existence of two types of glucoamylase-specific mRNAs, as demonstrated by in vitro translation and Northern blot analysis studies.

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In vitro translation of the intermediate filament proteins desmin and vimentin

Molecular and Cellular Biology ◽

10.1128/mcb.1.4.303-309.1981 ◽

1981 ◽

Vol 1 (4) ◽

pp. 303-309

Author(s):

C M O'Connor ◽

D J Asai ◽

C N Flytzanis ◽

E Lazarides

Keyword(s):

Smooth Muscle ◽

Intermediate Filament ◽

Messenger Rna ◽

Cyclic Adenosine Monophosphate ◽

Adenosine Monophosphate ◽

In Vitro Translation ◽

Messenger Rnas ◽

Intermediate Filament Proteins

Polyadenylated ribonucleic acid (RNA) was isolated from chicken skeletal and smooth muscle and translated in a cell-free rabbit reticulocyte system. Both types of muscle tissue contain messenger RNAs that code for the intermediate filament proteins desmin and vimentin, and the relative concentrations of the two translation products reflect the prevalence of the two proteins in vivo. Desmin synthesis represents a greater proportion of the total protein synthesis from smooth muscle RNA than from skeletal muscle RNA, whereas the converse is true of vimentin synthesis. Fractionation of the RNA on formamide-containing sucrose gradients before translation indicates that the desmin messenger RNA is larger than the vimentin messenger RNA and contains an extensive noncoding segment. The desmin and vimentin messages code predominantly for the non-phosphorylated forms of desmin and vimentin. However, the ratio of phosphorylated to unphosphorylated forms of the proteins could be increased by adding cyclic adenosine monophosphate-dependent kinase activity to the translation mixtures. These results suggest that desmin and vimentin are each synthesized from a single messenger RNA species and that posttranslational phosphorylation generates the additional isoelectric variants of each which are observed in vivo.

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In vitro translation of the intermediate filament proteins desmin and vimentin.

Molecular and Cellular Biology ◽

10.1128/mcb.1.4.303 ◽

1981 ◽

Vol 1 (4) ◽

pp. 303-309 ◽

Cited By ~ 7

Author(s):

C M O'Connor ◽

D J Asai ◽

C N Flytzanis ◽

E Lazarides

Keyword(s):

Smooth Muscle ◽

Intermediate Filament ◽

Messenger Rna ◽

Cyclic Adenosine Monophosphate ◽

Adenosine Monophosphate ◽

In Vitro Translation ◽

Messenger Rnas ◽

Intermediate Filament Proteins

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Soluble Thrombomodulin Purified from Human Urine Exhibits a Potent Anticoagulant Effect In Vitro and In Vivo

Thrombosis and Haemostasis ◽

10.1055/s-0038-1653872 ◽

1995 ◽

Vol 73 (05) ◽

pp. 805-811 ◽

Cited By ~ 12

Author(s):

Yasuo Takahashi ◽

Yoshitaka Hosaka ◽

Hiromi Niina ◽

Katsuaki Nagasawa ◽

Masaaki Naotsuka ◽

...

Keyword(s):

Human Urine ◽

Specific Activity ◽

Anticoagulant Activity ◽

Rabbit Lung ◽

Soluble Thrombomodulin ◽

Molecular Weights ◽

Dose Dependent Fashion ◽

Dose Dependent

SummaryWe examined the anticoagulant activity of two major molecules of soluble thrombomodulin purified from human urine. The apparent molecular weights of these urinary thrombomodulins (UTMs) were 72,000 and 79,000, respectively. Both UTMs showed more potent cofactor activity for protein C activation [specific activity >5,000 thrombomodulin units (TMU)/mg] than human placental thrombomodulin (2,180 TMU/mg) and rabbit lung thrombomodulin (1,980 TMU/mg). The UTMs prolonged thrombin-induced fibrinogen clotting time (>1 TMU/ml), APTT (>5 TMU/ml), TT (>5 TMU/ml) and PT (>40 TMU/ml) in a dose-dependent fashion. These effects appeared in the concentration range of soluble thrombomodulins present in human plasma and urine. In the rat DIC model induced by thromboplastin, administration of UTMs by infusion (300-3,000 TMU/kg) restored the hematological abnormalities derived from DIC in a dose-dependent fashion. These results demonstrate that UTMs exhibit potent anticoagulant and antithrombotic activities, and could play a physiologically important role in microcirculation.

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Toxicity of Heparinoids, with Special Reference to the Precipitation of Fibrinogen

Thrombosis and Haemostasis ◽

10.1055/s-0038-1655587 ◽

1964 ◽

Vol 12 (01) ◽

pp. 232-261 ◽

Cited By ~ 2

Author(s):

S Sasaki ◽

T Takemoto ◽

S Oka

Keyword(s):

Molecular Weight ◽

Dextran Sulfate ◽

Anticoagulant Activity ◽

Molecular Structures ◽

Severe Reaction ◽

Clinical Use ◽

Molecular Weights ◽

Close Relationship

SummaryTo demonstrate whether the intravascular precipitation of fibrinogen is responsible for the toxicity of heparinoid, the relation between the toxicity of heparinoid in vivo and the precipitation of fibrinogen in vitro was investigated, using dextran sulfate of various molecular weights and various heparinoids.1. There are close relationships between the molecular weight of dextran sulfate, its toxicity, and the quantity of fibrinogen precipitated.2. The close relationship between the toxicity and the precipitation of fibrinogen found for dextran sulfate holds good for other heparinoids regardless of their molecular structures.3. Histological findings suggest strongly that the pathological changes produced with dextran sulfate are caused primarily by the intravascular precipitates with occlusion of the capillaries.From these facts, it is concluded that the precipitates of fibrinogen with heparinoid may be the cause or at least the major cause of the toxicity of heparinoid.4. The most suitable molecular weight of dextran sulfate for clinical use was found to be 5,300 ~ 6,700, from the maximum value of the product (LD50 · Anticoagulant activity). This product (LD50 · Anticoagulant activity) can be employed generally to assess the comparative merits of various heparinoids.5. Clinical use of the dextran sulfate prepared on this basis gave satisfactory results. No severe reaction was observed. However, two delayed reactions, alopecia and thrombocytopenia, were observed. These two reactions seem to come from the cause other than intravascular precipitation.

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Heterogeneity of messenger RNA that encodes the rat insulin receptor is limited to the domain of exon 11. Analysis by RNA heteroduplex mapping, amplification of cDNA, and in vitro translation

Diabetes ◽

10.2337/diabetes.41.10.1293 ◽

1992 ◽

Vol 41 (10) ◽

pp. 1293-1300 ◽

Cited By ~ 7

Author(s):

B. J. Goldstein ◽

A. L. Dudley

Keyword(s):

Insulin Receptor ◽

Messenger Rna ◽

In Vitro Translation ◽

Exon 11

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Exploiting Anti-Inflammation Effects of Flavonoids in Chronic Inflammatory Diseases

Current Pharmaceutical Design ◽

10.2174/1381612826666200408101550 ◽

2020 ◽

Vol 26 (22) ◽

pp. 2610-2619 ◽

Cited By ~ 2

Author(s):

Tarique Hussain ◽

Ghulam Murtaza ◽

Huansheng Yang ◽

Muhammad S. Kalhoro ◽

Dildar H. Kalhoro

Keyword(s):

Oxidative Stress ◽

Chronic Diseases ◽

Inflammatory Diseases ◽

Therapeutic Option ◽

Cellular Level ◽

Antiinflammatory Drugs ◽

Suitable Alternative ◽

Chronic Inflammatory Diseases

Background: Inflammation is a complex response of the host defense system to different internal and external stimuli. It is believed that persistent inflammation may lead to chronic inflammatory diseases such as, inflammatory bowel disease, neurological and cardiovascular diseases. Oxidative stress is the main factor responsible for the augmentation of inflammation via various molecular pathways. Therefore, alleviating oxidative stress is effective a therapeutic option against chronic inflammatory diseases. Methods: This review article extends the knowledge of the regulatory mechanisms of flavonoids targeting inflammatory pathways in chronic diseases, which would be the best approach for the development of suitable therapeutic agents against chronic diseases. Results: Since the inflammatory response is initiated by numerous signaling molecules like NF-κB, MAPK, and Arachidonic acid pathways, their encountering function can be evaluated with the activation of Nrf2 pathway, a promising approach to inhibit/prevent chronic inflammatory diseases by flavonoids. Over the last few decades, flavonoids drew much attention as a potent alternative therapeutic agent. Recent clinical evidence has shown significant impacts of flavonoids on chronic diseases in different in-vivo and in-vitro models. Conclusion: Flavonoid compounds can interact with chronic inflammatory diseases at the cellular level and modulate the response of protein pathways. A promising approach is needed to overlook suitable alternative compounds providing more therapeutic efficacy and exerting fewer side effects than commercially available antiinflammatory drugs.

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