Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Puromycin”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 145 records · Page 8Linked to original sources
PubMed1965

PUROMYCIN: EFFECT ON MESSENGER RNA SYNTHESIS AND BETA-GALACTOSIDASE FORMATION IN ESCHERICHIA COLI 15T.

Incubation of Escherichia coli 15T(-) in the presence of puromycin inhibits the inducible formation of beta-galactosidase to a greater extent than it inhibits protein synthesis. In E. coli 33.00 beta-galactosidase formation is also more sensitive to the presence of puromycin than is protein synthesis. In the presence of glycerol (but not in its absence) puromycin prevents the production of messenger RNA for beta-galactosidase, presumably as a result of catabolite repression.

Escherichia coli↗
PubMed1985

Effects of the aminonucleoside of puromycin on glomerular epithelial cells in vitro.

Glomerular epithelial cells (GECs) in vitro provide a useful model for the study of the mechanism(s) underlying the nephrotic syndrome of rats induced by the aminonucleoside of puromycin (PAN). Some of the toxicities of PAN are nonspecific, in that the constituent molecules of PAN (adenosine and puromycin) cause similar effects in vitro. These include GEC blebbing and rounding, reduced uptake of precursors of protein (leucine) and glycoprotein (glucosamine) synthesis, and increased permeability of the GEC membrane to adenosine. Some of the effects of PAN are not reproduced by adenosine or puromycin and are inhibited by the simultaneous presence of N6-monomethyl adenosine (MMA), a PAN analog and an in vivo blocker of nephrosis due to PAN. These processes may be related to the nephrotic syndrome and include the loss of adhesion to plastic; a reduction in the incorporation of 14C-glucosamine and 35S-sulfate both into molecules removable from the GEC surface by neuraminidase and into those moieties precipitated from the culture media by TCA; a marked reduction in the "ordering" of the lipids of the rigid GEC membrane, which is possibly dependent upon cell-surface proteins. These morphologic alterations in GECs and in the distribution of negatively charged molecules, which are either secreted or on the cell surface, correlate with observations made in PAN-induced nephrosis in rats in vivo. These include changes in the turnover and the array of sialic acid and heparan sulfate glycoprotein on the GECs and the glomerular basement membrane. The in vitro sensitivity of GECs to PAN and the effects of MMA suggest a role for these cells in in vivo aminonucleoside nephrotoxicity, where alterations in both the morphology and the anionic topology of GECs participate in the development of proteinuria.

Adenosine↗
PubMed2006

C-terminal modifications of a protein by UAG-encoded incorporation of puromycin during in vitro protein synthesis in the absence of release factor 1.

Deactivation of release factor 1 by polyclonal antibodies in an in vitro translation system, which was used to express the esterase gene, led to the reversible elimination of naturally occurring termination. This technique allowed the antibiotic puromycin to be used as an acceptor substrate for the peptidyl residue in the peptidyl-transferase reaction. This resulted in more than 80 % yield of protein with C-terminally incorporated puromycin. pCpPuromycin that was either conjugated with the Cy3 fluorophor or biotin by N4 alkylation of cytosine, also acted as an acceptor substrate for the peptidyl-transferase reaction and was incorporated into the protein C terminus. The resulting conjugates possessed Cy3-specific fluorescence and affinity to streptavidin-coated surfaces, respectively. This left the enzymatic activity of the reporter protein unaffected. It was also shown that extension of puromycin on its 5'-hydroxyl end by up to ten deoxyoligonucleotides also allowed conjugation with the C terminus of in vitro translated protein when RF1-dependent termination was suppressed. However, the conjugation yield decreased upon addition of more than six nucleotides.

Animals↗
PubMed1975

Combined light and electron-microscope morphometric studies of acute puromycin aminonucleoside nephropathy in rats.

Morphometric observations were made on rats injected subcutaneously daily with puromycin aminonucleoside after two, four, six and eight daily injections. As a result it was possible to correlate the morphological alterations of the various glomerular components with the biochemical manifestations of the nephrotic syndrome particularly the onset of proteinuria. There was already significant loss of foot processes of the glomerular epithelial cells by the 2nd day, that is before the onset of proteinuria, suggesting that the loss of foot processes is a consequence of some metabolic impairment produced by the puromycin aminonucleoside which also subsequently causes the proteinuria. Swelling of the glomerular epithelial cells became significant by the 6th and 8th day of injection after the development of proteinuria, suggesting that it is a consequence of the increased amount of protein in the glomerular filtrate. Two independent morphometric methods suggest a decrease in the amount of glomerular basement membrane. Unfortunately because of difficulties in the determination of mean glomerular volumes it is not possible to be absolutely certain that this is a true finding, however it is what would be expected if the synthesis of basement membrane was depressed by the puromycin aminonucleoside.

Acute Disease↗
PubMed1991

Chromatin behaviour under influence of puromycin and 6-DMAP at different stages of mouse oocyte maturation.

Preovulatory mouse oocytes were cultured in vitro up to each subsequent stages of maturation: germinal vesicle (GV), germinal vesicle breakdown (GVBD), groups of not yet individualized bivalents, circular bivalents, late prometaphase I, metaphase I, anaphase I and telophase I. The stages were identified in living oocytes by fluorescence microscopy using Hoechst 33342 as a specific vital dye. Oocytes from each stage of development developed in vitro and ovulated metaphase II oocytes were subsequently cultured in the presence of puromycin or 6-dimethylaminopurine (6-DMAP), an inhibitor of protein phosphorylation. The effects on chromatin of these drugs were studied during and at the end of culture by fluorescence and electron microscopy. We found that puromycin and 6-DMAP stop meiosis when applied at all stages of oocyte maturation, except for metaphase II. Oocytes at this stage are activated by puromycin. Reaction of the oocytes to the two drugs is different at GV and at metaphase II. All of the other stages react to the drugs by chromatin compaction, which can be followed by chromatin decondensation to form a nucleus. Our results suggest that late prophase chromatin condensation, bivalent individualization and retention of their individuality, as well as individualization of monovalents from telophase and retention of their individuality at metaphase II, are dependent on protein phosphorylation. The events occurring between metaphase I and telophase I are independent of protein synthesis and phosphorylation. The events occurring between metaphase II and formation of the nucleus are independent of protein synthesis.

Adenine↗
PubMed1987

Puromycin enhances 20-hydroxyecdysone-induced protein synthesis in wing discs of Drosophila melanogaster.

The effect of cycloheximide and puromycin on 20-hydroxyecdysone-induced protein synthesis in wing discs of Drosophila melanogaster has been studied by one-dimensional and two-dimensional SDS polyacrylamide electrophoresis. It is found that puromycin, but not cycloheximide, when applied simultaneously with the hormone enhanced the hormone-induced synthesis of the 'early' and 'late' proteins. However, when puromycin was applied after hormone treatment, only the 'late' proteins were induced. The possible implication of these observations is discussed.

Animals↗
PubMed1975

The effect of puromycin and cycloheximide on vacuole formation and exocytosis in Tetrahymena pyriformis GL-9.

It has been shown that both puromycin and cycloheximide, at concentrations of 434 and 100 mug/ml respectively, produce a marked inhibition of vacuole formation and exocytosis in Tetrahymena pyriformis GL-9. These effects were analysed in a quantitative manner. At the same time as these inhibitions occurred the incorporation of 1-C14 leucine into trichloroacetic acid precipitable material was inhibited by 90% and 100% respectively over a 40 min period. This inhibition of protein synthesis by cycloheximide occurred almost immediately, whereas the inhibition of vacuole formation and egestion was delayed. The results suggested that the latter processes were dependent upon a continuing supply of proteinaceous material, of which there was only a small store within the cell. Cycloheximide inhibited exocytosis completely -nder the conditions employed (with 100% inhibition of protein synthesis) whereas puromycin (with a 90% inhibition of protein synthesis) only inhibited it by about 50%. This suggested that the amount of newly synthesized protein required for the exocytic egestion process was very small in relation to the total cell requirement for protein synthesis. The entry of both inhibitors into the cell was by means other than vacuole formation. Puromycin appeared to have some effect on vacuole formation which was unconnected with protein synthesis. Microscopic observations of living cells indicated that oral apparatus function and endocytic vacuole formation were probably both affected by the inhibitors. Chloramphenicol, at 200 mug/ml, had little effect on vacuole formation by starved cells with an exposure of an hour. The uptake of 1-C14 leucine from the growth medium was found to be a selective process, giving a concentration of about 2000 times into the cells over a 1 hr period. The results are discussed

Bacterial Proteins↗
PubMed1990

The renal functional and structural consequences of corticosteroid and angiotensin-converting enzyme inhibitor therapy in chronic puromycin aminonucleoside nephropathy.

Glomerular diseases are characterized by increased urinary protein excretion. Treatment of this abnormality frequently involves administration of corticosteroids and angiotensin-converting enzyme inhibitors. There has been much recent interest in the potential impact of these drugs on progressive renal dysfunction, since they have opposing effects on intraglomerular hemodynamics. Therefore, we investigated the effect of methylprednisolone or captopril treatment on animals with chronic puromycin aminonucleoside nephropathy. In rats given a single injection of puromycin aminonucleoside, 15 mg/100 g body weight, both methylprednisolone and captopril significantly reduced proteinuria at 6 months [83 +/- 14 untreated (n = 7), 34 +/- 6 with methylprednisolone (n = 8), and 6 +/- 1 mg/24 h with captopril (n = 5), P less than 0.001]. Segmental glomerulosclerosis occurred with equal frequency in the untreated (7.8 +/- 2.3%) and methylprednisolone-treated rats (5.0 +/- 1.11%), but was significantly reduced by the administration of captopril (1.0 +/- 0.5%, P less than 0.001). We conclude that in chronic puromycin aminonucleoside nephropathy, treatment with corticosteroids reduces proteinuria without increasing the incidence of segmental glomerulosclerosis. Therapy with an angiotensin-converting enzyme inhibitor substantially decreases proteinuria and lessens the severity of glomerular scarring.

Adrenal Cortex Hormones↗
PubMed1985

Effect of puromycin on sugar transport in isolated rat adipocytes.

This study was performed to determine whether puromycin effects sugar transport into isolated rat adipocytes. Time-course and kinetic studies demonstrated that puromycin competitively inhibited 3-O-methylglucose transport. The data indicate that there is an acute effect of puromycin on sugar transport via competitive inhibition that is independent of the inhibition of protein synthesis.

3-O-Methylglucose↗
PubMed1982

Plasma and urinary lipids and lipoproteins during the development of nephrotic syndrome induced in the rat by puromycin aminonucleoside.

This study was undertaken to ascertain whether the alterations of plasma lipoproteins found in nephrotic syndrome induced by puromycin aminonucleoside were due to nephrotic syndrome per se, or, at least in part, to the aminonucleoside. The purpose of the present study was to investigate the changes in plasma and urinary lipoproteins during the administration of puromycin aminonucleoside (20 mg/kg for 7 days) and the subsequent development of nephrotic syndrome. Since massive albuminuria occurred after 6 days of treatment, the time-course study was divided into two stages: pre-nephrotic stage (day 1-5) and nephrotic stage (day 6-11). In pre-nephrotic stage the plasma level of fatty acids, triacylglycerol and VLDL decreased while that of phospholipid, cholesteryl esters and HDL remained constant. Plasma apolipoprotein A-I tended to increase (40% increase at day 5). At the beginning of nephrotic stage (day 6) the concentration of plasma albumin dropped to a very low level, while that of apolipoprotein A-I increased abruptly (4-fold increase) and continued to rise, although less steeply, in the following days. The plasma concentration of HDL followed the same pattern. Plasma VLDL and LDL increased at a later stage (day 9). Plasma apolipoprotein A-I was found not only in HDL (1.063-1.210 g/ml) but also in the LDL density class (1.025-1.050 g/ml). In the pre-nephrotic stage lipoproteinuria was negligible, while in the early nephrotic stage the urinary loss of plasma lipoproteins consisted mainly of HDL. These observations indicate that puromycin aminonucleoside alters plasma lipoproteins by lowering VLDL and increasing HDL. It is likely that the early and striking increase of plasma HDL found in nephrotic rats is related to a direct effect of the drug on HDL metabolism.

Animals↗
PubMed1975

fMet-tRNA F Met binding and peptidyl transferase function in free and bound ribosomes from normal and puromycin aminonucleoside-treated rats.

Treatment of rats with the aminonucleoside of puromycin, which increases the incorporation of labelled phenylalanyl-tRNA into polypeptide chains in liver ribosome preparations studied in vitro, did not change the factor-dependent binding of fMet-tRNA f Met to ribosomes nor the peptidyl transferase function of the ribosomes. Peptidyl transferase function, as measured by fMet-tRNA f Met-puromycin formation, was comparable in the free and bound ribosome preparations. Similarly, the factor-dependent binding of fMet-tRNA f Met to ribosomes was the same in free ribosome preparations obtained from rat liver as it was in bound ribosome preparations that had been freed of membranes by puromycin incubation and high salt wash.

Acyltransferases↗
PubMed1976

Attachment of ribosomes to endoplasmic membranes in mouse pancreas. Degranulation in vivo caused by the inducers of autophagocytosis neutral red, vinblastine, puromycin, and cadmium ions, and prevention by cycloheximide.

The present investigation was undertaken to discover whether in vivo inducers of autophagocytosis such as neutral red (0.40 mg/g body weight), cadmium chloride (0.15 mg/animal), vinblastine sulfate (7.5 mg/kg b.w.), and puromycin dihydrochloride (0.20 mg/g b.w.) are able to produce degranulation of rough surfaced endoplasmic reticulum (ER) of pancreatic acinar cells as we suggested earlier. Using a modified method of Blobel and Potter about 30% of the total ribosomes of untreated control pancreas were recovered in the free form, and 70% in the membrane-bound form. Cycloheximide (0.20 mg/g body weight) had no effect on this distribution of ribosomes, while neutral red, cadmium ions, vinblastine, and puromycin led to the presence of more free ribosomes: thus up to 70% of the total cytoplasmic ribosomes were recovered in the free form 30 to 60 min after treatments with the autophagic inducers. Pretreatments with cycloheximide prevented this shift and the distribution of ribosomes remained normal. On the basis of these and previous results we conclude that in pancreas an initial degranulation of the ER caused by these agents is a precondition of membrane transformation in autophagocytosis which is preventable by cycloheximide. Confirming the ultrastructural data of Longnecker et al. on rat pancreas, puromycin was shown to cause different forms of cellular injury including autophagocytosis. All forms of cellular injury were also prevented by pretreatment with cycloheximide in mouse pancreas.

Animals↗
PubMed1990

Interaction of puromycin with acceptor site of human placenta 80 S ribosomes.

The complex N-AcPhe-tRNA(Phe).poly(U).80 S ribosome from human placenta was treated with puromycin taken in various concentrations. Based on the kinetic data of N-acetylphenylalanyl-puromycin formation, the association constant of puromycin with the acceptor site of the ribosome was estimated to be (3.96 +/- 0.84) x 10(4) M-1 at 37 degrees C.

Humans↗
PubMed1983

Radioactive puromycin formation as an assay for the proportion of active ribosomes in mammalian cells: correlation with polysome profiles under different physiological conditions.

We have established optimal conditions for the in vitro formation of peptidyl-[3H] puromycin by mammalian ribosomes. The growth conditions of cultured Ehrlich ascites tumor cells were manipulated to produce changes in the polysome profiles. The correlation between polysome content and peptidyl-[3H] puromycin formation was linear and excellent when different cell densities were compared. The percentage of ribosomes actively engaged in protein synthesis, calculated from the number of 3H-peptide bonds formed, was similar in rapidly growing Ehrlich cells (47%) and in young rat gastrocnemius muscle (44%). Starvation resulted in a 50% reduction in the number of puromycin-reactive ribosomes in rat gastrocnemius.

Animals↗
PubMed1984

Suppression of sexual behavior and localization of [3H] puromycin after intracranial injection in the rat.

Bilateral intracranial injections of puromycin (10 micrograms/0.5 microliter vehicle) into the preoptic area (POA) of steroid-primed ovariectomized rats resulted in a significant decrease in the lordosis response when compared to saline treated controls. To determine the extent of puromycin diffusion after intracranial injection, [3H] puromycin was injected into the right POA of ovariectomized rats. Neural regions anterior, posterior and superior to the POA, and the right and left POA were assessed for tritium activity 0.5, 6 and 24 hours after stereotaxic surgery. The activity was primarily located at the injection site or in the injection tract. The highest amount of activity external to the injection site or injection tract was found in the right ventromedial hypothalamus.

Animals↗
PubMed1995

Arginine vasopressin gene expression in rats with puromycin-induced nephrotic syndrome.

Nephrotic syndrome is characterized by water and sodium retention, which leads to edema formation. The nonosmotic stimulation of arginine vasopressin (AVP) release from the pituitary gland has been implicated to be one of the important factors of abnormal water retention in patients with nephrotic syndrome. It is not known, however, whether nephrotic syndrome is associated with stimulation of hypothalamic vasopressin gene expression. Puromycin aminonucleoside is known to cause altered glomerular permeability, which results in experimental nephrotic syndrome in rats. In the present study, therefore, AVP gene expression has been studied in the hypothalamus of rats with puromycin aminonucleoside-induced nephrotic syndrome (PNS). Nephrotic syndrome was induced by a single intravenous injection of puromycin aminonucleoside (50 mg/kg body weight). Nephrotic syndrome was confirmed by urinary protein excretion (control 20.8 +/- 3.5 mg/24 hr v PNS 273.9 +/- 41.4 mg/24 hr; P < 0.0001, n = 6) and serum albumin concentrations (control 4.52 +/- 0.07 g/dL v PNS 2.96 +/- 0.22 g/dL; P < 0.001, n = 6). In PNS rats, plasma AVP was significantly higher than in control rats (control 0.77 +/- 0.10 pg/mL v PNS 2.13 +/- 0.42 pg/mL; P < 0.005, n = 12), even though there were no differences in plasma osmolality (control 292.0 +/- 2.0 mOsm/kg H2O v PNS 290.3 +/- 2.5 mOsm/kg H2O; P = NS, n = 12) or serum sodium concentration (control 142.7 +/- 0.7 v PNS 142.1 +/- 1.1; PNS, n = 12).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1995

Synthesis of N-acetylglucosaminyl asparagine-substituted puromycin analogues.

As part of our project aimed to introduce specifically glycosylated amino acids into proteins, new glycosylated puromycin analogues were chemically synthesized. Introduction of a free N-acetylglucosaminyl asparaginyl side chain abolished the activity of puromycin completely, but when the sugar OH groups were rendered increasingly hydrophobic by acetylation or benzylation, up to 8% of the activity was recovered. The results of our preliminary inhibition tests suggest that the interaction of puromycin analogues and therefore also of glycosylated aminoacyl tRNA, with the ribosomal A site increase with hydrophobicity of the modifying protecting groups.

Acetylglucosamine↗
PubMed2006

The pur3 gene from the pur cluster encodes a monophosphatase essential for puromycin biosynthesis in Streptomyces.

The pur3 gene of the puromycin (pur) cluster from Streptomyces alboniger is essential for the biosynthesis of this antibiotic. Cell extracts from Streptomyces lividans containing pur3 had monophosphatase activity versus a variety of mononucleotides including 3'-amino-3'-dAMP (3'-N-3'-dAMP), (N6,N6)-dimethyl-3'-amino-3'-dAMP (PAN-5'-P) and AMP. This is in accordance with the high similarity of this protein to inositol monophosphatases from different sources. Pur3 was expressed in Escherichia coli as a recombinant protein and purified to apparent homogeneity. Similar to the intact protein in S. lividans, this recombinant enzyme dephosphorylated a wide variety of substrates for which the lowest Km values were obtained for the putative intermediates of the puromycin biosynthetic pathway 3'-N-3'-dAMP (Km = 1.37 mM) and PAN-5'-P (Km = 1.40 mM). The identification of this activity has allowed the revision of a previous proposal for the puromycin biosynthetic pathway.

Cloning, Molecular↗