Molecular cloning of metallothionein cDNA and analysis of metallothionein gene expression in winter flounder tissues

1989 ◽  
Vol 67 (10) ◽  
pp. 2520-2527 ◽  
Author(s):  
King Ming Chan ◽  
William S. Davidson ◽  
Choy L. Hew ◽  
Garth L. Fletcher
Keyword(s):  
Cdna Library ◽  
Untranslated Region ◽  
Cadmium Chloride ◽  
Gill Filament ◽  
Winter Flounder ◽  
Mrna Levels ◽  
Pseudopleuronectes Americanus ◽  
Coding Region ◽  
Liver And Kidney ◽  
Time Required

Investigations into the precise role played by metallothionein (MT) in heavy-metal metabolism have been hampered by difficulties in positively identifying and quantifying MT in fish tissues. This study describes the development of an antisense MT RNA (cRNA) probe that will enable MT mRNA levels to be measured with a high degree of specificity and precision. Cadmium chloride administration induces the producton of MT mRNA in the liver and kidney of winter flounder (Pseudopleuronectes americanus). Poly(A)+ RNA purified from liver samples of winter flounder after cadmium chloride injections was used to construct a cDNA library. Several recombinant clones made complementary to MT mRNA were selected from this cDNA library by an oligonucleotide derived from the N-terminal amino acid sequence of winter flounder metallothionein. Sequence analysis of two of the cDNA inserts gave the structure of the entire 3′ untranslated region, a coding region corresponding to winter flounder MT and 49 nucleotides of the 5′ untranslated region. One of the flounder MT cDNAs, pWFMTC4, was subcloned into a RNA probe plasmid and transcribed to produce antisense MT RNA (cRNA). The MT cRNA was then used to detect the induction of MT mRNA production in the liver of winter flounder, following the administration of Cu2+, Zn2+, Cd2+, Pb2+, and Hg2+. The time required for the induction of hepatic MT mRNA by a single injection of Cd2+ was approximately 96 h. Dexamethasone did not induce an increase of MT mRNA in any of the winter flounder tissues examined (liver, kidney, heart, brain, intestinal scrape, and gill filament), whereas Cd2+ induced MT mRNA in all of the tissues except brain, where the constitutive level of expression was high.

scholarly journals Role of the 5′-untranslated region of mRNA in the synthesis of S-adenosylmethionine decarboxylase and its regulation by spermine

1994 ◽  
Vol 302 (3) ◽  
pp. 765-772 ◽  
Author(s):  
L M Shantz ◽  
R Viswanath ◽  
A E Pegg
Keyword(s):  
Secondary Structure ◽  
Untranslated Region ◽  
Fold Increase ◽  
Negative Regulator ◽  
Mrna Levels ◽  
Coding Region ◽  
Polyamine Biosynthesis ◽  
Adenosylmethionine Decarboxylase ◽  
Spermine Synthase ◽  
Synthase Inhibitor

S-Adenosylmethionine decarboxylase (AdoMetDC), a rate-limiting enzyme in polyamine biosynthesis, is regulated by polyamines at the levels of both transcription and translation. Two unusual features of AdoMetDC mRNA are a long (320 nt) 5′-untranslated region (5′UTR), which is thought to contain extensive secondary structure, and a short (15 nt) open reading frame (ORF) within the 5′UTR. We have studied the effects of altering these elements on both the expression of AdoMetDC and its regulation by n-butyl-1,3-diaminopropane (BDAP), a spermine synthase inhibitor. Human AdoMetDC cDNAs containing alterations in the 5′UTR, as well as chimaeric constructs in which the AdoMetDC 5′UTR was inserted ahead of the luciferase-coding region, were transfected into COS-7 cells. Construct pSAM320, which contains all of the 5′UTR, the AdoMetDC protein-coding region and the 3′UTR, was expressed poorly (2-fold over the endogenous activity). Deletion of virtually the entire 5′UTR, leaving nt -12 to -1, increased expression 59-fold, suggesting that 5′UTR acts as a negative regulator. The same effect was seen when the 27 nt at the extreme 5′ end were removed (pSAM293, 47-fold increase), or when the internal ORF which is present in this region was destroyed by changing the ATG to CGA (pSAM320-ATG, 38-fold increase). The expression and regulation of pSAM44 (made by deleting nt -288 to -12), which has very little predicted secondary strucutre, was very similar to that of pSAM320 indicating that the terminal 27 nt including the internal ORF rather than extensive secondary structure may be responsible for the low basal levels of AdoMetDC expression. These results, confirmed using luciferase constructs, suggest that the negative effect on expression is predominantly due to the internal ORF. Depletion of spermine by BDAP increased the expression from pSAM320 more than 5-fold without affecting AdoMetDC mRNA levels. Expression from pSAM293 was unchanged by spermine depletion, whereas that from pSAM320-ATG was increased 2.5-fold. These results indicate the presence of a spermine response element in the first 27 nt of the 5′UTR that may include but is not entirely due to the internal ORF.

Polyamine synthesis in liver and kidney of flounder in response to methylmercury

1976 ◽  
Vol 231 (2) ◽  
pp. 560-564 ◽  
Author(s):  
CA Manen ◽  
B Schmidt-Nielsen ◽  
DH Russell
Keyword(s):  
Ornithine Decarboxylase ◽  
Single Injection ◽  
Recovery Phase ◽  
Winter Flounder ◽  
Decarboxylase Activity ◽  
Pseudopleuronectes Americanus ◽  
Toxic Dose ◽  
Polyamine Synthesis ◽  
Adenosylmethionine Decarboxylase ◽  
Liver And Kidney

The effect of methylmercury administration on polyamine synthesis was studied in the liver and kidney of the winter flounder (Pseudopleuronectes americanus). A single injection of methylmercury resulted in five- and sevenfold elevations of ornithine decarboxylase activity in the liver and kidney within 15 and 45 h, respectively. There were elevations of both putrescine- and spermidine-stimulated S-adenosylmethionine decarboxylase activities (approximately 1.5-fold) in both tissues. Evaluation of the polyamine accumulation patterns in these tissues indicated that in the liver all three polyamines increased in concentration until 48 h and then decline. In the kidney, the concentration of putrescine increased steadily until it was 200% of control at 72 h and then declined. Spermidine concentration decreased throughout the time studied and was 17% of control at 1 wk. There was no significant change in the concentration of spermine throughout the period studied. The changes in the polyamine pools and in the activities of the polyamine biosynthetic enzymes after methylmercury administration are consistent with an involvement of the polyamines in the recovery phase to a toxic dose of methylmercury.

A preprogalanin cDNA from the turtle pituitary and regulation of its gene expression

2007 ◽  
Vol 292 (4) ◽  
pp. R1649-R1656 ◽  
Author(s):  
John Yuh-Lin Yu ◽  
Chin-Hon Pon ◽  
Hui-Chen Ku ◽  
Chih-Ting Wang ◽  
Yung-Hsi Kao
Keyword(s):  
Mrna Expression ◽  
Untranslated Region ◽  
Signal Sequence ◽  
Biological Effects ◽  
In Vitro Study ◽  
The Body ◽  
Mrna Levels ◽  
Coding Region ◽  
Reading Frame

Galanin is a hormone 29 or 30 amino acids (aa) long that is widely distributed within the body and exerts numerous biological effects in vertebrates. To fully understand its physiological roles in reptiles, we analyzed preprogalanin cDNA structure and expression in the turtle pituitary. Using the Chinese soft-shell turtle ( Pelodiscus sinensis order Testudines), we obtained a 672-base pair (bp) cDNA containing a 99-bp 5′-untranslated region, a 324-bp preprogalanin coding region, and a 249-bp 3′-untranslated region. The open-reading frame encoded a 108-aa preprogalanin protein with a putative 23-aa signal sequence at the NH2 terminus. Based on the location of putative Lys-Arg dibasic cleavage sites and an amidation signal of Gly-Lys-Arg, we propose that turtle preprogalanin is processed to yield a 29-aa galanin peptide with Gly1 and Thr29 substitutions and a COOH-terminal amidation. Sequence comparison revealed that turtle preprogalanin and galanin-29 had 48–81% and 76–96% aa identities with those of other vertebrates, respectively, suggesting their conservative nature. Expression of the turtle galanin gene was detected in the pituitary, brain, hypothalamus, stomach, liver, pancreas, testes, ovaries, and intestines, but not in the adipose or muscle tissues, suggesting tissue-dependent differences. An in vitro study that used pituitary tissue culture indicated that treatment with 17β-estradiol, testosterone, or gonadotropin-releasing hormone resulted in increased galanin mRNA expression with dose- or time-dependent differences, whereas leptin and neuropeptide Y reduced galanin mRNA levels. These results suggest a hormone-dependent effect on hypophyseal galanin mRNA expression.

The effects of long day length on liver antifreeze mRNA in the winter flounder, Pseudopleuronectes americanus

1984 ◽  
Vol 62 (8) ◽  
pp. 1456-1460 ◽  
Author(s):  
Ron M. Fourney ◽  
Garth L. Fletcher ◽  
Choy L. Hew
Keyword(s):  
Blot Hybridization ◽  
Winter Flounder ◽  
Day Length ◽  
Control Fish ◽  
Pituitary Hormone ◽  
Northern Blot Hybridization ◽  
Mrna Levels ◽  
Pseudopleuronectes Americanus ◽  
Long Day ◽  
Afp Mrna

The effect of photoperiod on the seasonal accumulation of winter flounder (Pseudopleuronectes americanus) antifreeze polypeptide (AFP) mRNA in the liver was examined. AFP mRNA levels were identified and measured by cytoplasmic dot hybridization and Northern blot hybridization procedures utilizing a nick-translated antifreeze genomic clone. Flounder maintained under conditions of 15-h long day length have both a delayed appearance and decreased accumulation of AFP mRNA. December flounder maintained under long day length had the most significant decrease in AFP mRNA levels. It was estimated that these fish contained less than 0.6% of the AFP mRNA normally found in control fish. The seasonal fluctuation of AFP mRNA in both the experimental and control fish matched closely but preceded the rise and fall of plasma AFP levels. These results suggest that long day length suppresses the rate of transcription of antifreeze genes and supports the hypothesis that photoperiod may act as the initial cue for entraining the precise activation of AFP synthesis. A pituitary hormone may be the mediator.

Seasonal Distributions of Bottom Fishes in the Narragansett Bay Area: Seven-Year Variations in the Abundance of Winter Flounder (Pseudopleuronectes americanus)

1974 ◽  
Vol 31 (6) ◽  
pp. 1057-1066 ◽  
Author(s):  
H. Perry Jeffries ◽  
William C. Johnson
Keyword(s):  
Rhode Island ◽  
Homarus Americanus ◽  
Narragansett Bay ◽  
Winter Flounder ◽  
Pseudopleuronectes Americanus ◽  
Commercial Catch ◽  
Average Temperature ◽  
Climatic Trends ◽  
Bay Area ◽  
Time Required

Weekly bottom trawl samples taken in Narragansett Bay and Rhode Island Sound from January 1966 through December 1972 showed patterns of occurrence within a diverse assemblage of migratory and resident stocks. Relative abundance of winter flounder (Pseudopleuronectes americanus), the commonest species in the Bay, appeared to be associated with climatic trends but not with fishing pressure. Catch decreased 78% from 1968 to 1972. Average temperature during 30-mo periods, the time required for flounder to reach catchable size, explained 76% of variation in abundance through the study. Annual abundance in the Bay is also reflected 2–3 yr later in the commercial catch. A speculative explanation for control of the population in an estuarine nursery is developed, based on subtle climatic trends whose effects have been magnified many times over by competitive processes among migratory populations.The sand flounder (Scophthalmus aquosus), second in general abundance, varied far less than the winter flounder. Catches of the lobster (Homarus americanus) and winter flounder were directly related, both on a monthly as well as yearly basis. The remaining species of numerical importance appeared to avoid peak abundances of one another in the Bay and Sound; rarely did seasonal maxima of two or more species occur during the same month.

scholarly journals Homocysteine Down-regulates Cellular Glutathione Peroxidase (GPx1) by Decreasing Translation

2005 ◽  
Vol 280 (16) ◽  
pp. 15518-15525 ◽  
Author(s):  
Diane E. Handy ◽  
Yufeng Zhang ◽  
Joseph Loscalzo
Keyword(s):  
Glutathione Peroxidase ◽  
Untranslated Region ◽  
Stop Codon ◽  
Vascular Dysfunction ◽  
Lipid Peroxides ◽  
Mrna Levels ◽  
Coding Region ◽  
Sv40 Promoter ◽  
Secis Element

Hyperhomocysteinemia contributes to vascular dysfunction and an increase in the risk of cardiovascular disease. An elevated level of homocysteinein vivoand in cell culture systems results in a decrease in the activity of cellular glutathione peroxidase (GPx1), an intracellular antioxidant enzyme that reduces hydrogen peroxide and lipid peroxides. In this study, we show that homocysteine interferes with GPx1 protein expression without affecting transcript levels. Expression of the selenocysteine (SEC)-containing GPx1 protein requires special translational cofactors to “read-through” a UGA-stop codon that specifies SEC incorporation at the active site of the enzyme. These factors include a selenocysteine incorporation sequence (SECIS) in the 3′-untranslated region of the GPx1 mRNA and cofactors involved in the biosynthesis and translational insertion of SEC. To monitor SEC incorporation, we used a reporter gene system that has a UGA codon within the protein-coding region of the luciferase mRNA. Addition of either the GPx1 or GPx3 SECIS element in the 3′-untranslated region of the luciferase gene stimulated read-through by 6–11-fold in selenium-replete cells; absence of selenium prevented translation. To alter cellular homocysteine production, we used methionine in the presence of aminopterin, a folate antagonist, co-administered with hypoxanthine and thymidine (HAT/Met). This treatment increased homocysteine levels in the media by 30% (p< 0.01) and decreased GPx1 enzyme activity by 45% (p= 0.0028). HAT/Met treatment decreased selenium-mediated read-through significantly (p< 0.001) in luciferase constructs containing the GPx1 or GPx3 SECIS element; most importantly, the suppression of selenium-dependent read-through was similar whether an SV40 promoter or the GPx1 promoter was used to drive transcription of the SECIS-containing constructs. Furthermore, HAT/Met had no effect on steady-state GPx1 mRNA levels but decreased GPx1 protein levels, suggesting that this effect is not transcriptionally mediated. These data support the conclusion that homocysteine decreases GPx1 activity by altering the translational mechanism essential for the synthesis of this selenocysteine-containing protein.

Localization of cardiac (alpha)-myosin heavy chain mRNA is regulated by its 3′ untranslated region via mechanical activity and translational block

1997 ◽  
Vol 110 (23) ◽  
pp. 2969-2978 ◽  
Author(s):  
P. Goldspink ◽  
W. Sharp ◽  
B. Russell
Keyword(s):  
Myosin Heavy Chain ◽  
Cardiac Myocytes ◽  
Heavy Chain ◽  
Untranslated Region ◽  
Contractile Activity ◽  
Intracellular Localization ◽  
Mechanical Activity ◽  
Mrna Levels ◽  
Coding Region ◽  
Reporter Protein

We have altered the spontaneous contractile activity of neonatal cardiac myocytes in culture to investigate the re-lationship between mechanical forces, myofibril assembly, and the localization and translation of (alpha)-myosin heavy chain mRNA. Immunofluorescence and in situ hybridization techniques revealed that contracting myocytes display well aligned myofibrils and a diffuse distribution of (alpha)-myosin heavy chain mRNA. Inhibition of contractile activity with the calcium channel blocker verapamil (10 microM) resulted in myofibril disassembly and a perinuclear mRNA distribution within six hours. There was a significant decrease (P&lt;0. 05) of mRNA levels, 5 to 15 micron away from the nucleus following 6 hours of verapamil treatment compared with control cells. Inhibition of protein synthesis with cycloheximide (10 microM) also resulted in perinuclear mRNA localization despite having little effect on contractile activity or myofibril assembly. To determine if the 3′ untranslated region of (alpha)-myosin heavy chain mRNA was sufficient for localizing the entire message, a chimeric construct composed of beta-galactosidase coding region followed by (alpha)-myosin heavy chain 3′ untranslated region sequences was made as a reporter plasmid and transfected into cultured myocytes. A perinuclear accumulation of ss-galactosidase was exhibited in many of the contractile arrested cells (48.3+/−2.4%, n=7). In contrast, significantly fewer (P&lt;0.05) contracting control (29.1+/−3.3%, n=7) and strongly contracting, isoproterenol-treated cells (27.2+/−6.1%, n=3) exhibited a perinuclear localization of protein. The distribution of the reporter protein was not affected by the contractile state in cells transfected with a constitutively translated 3′UTR. We propose that mechanical activity of neonatal cardiac myocytes regulates the intracellular localization of alpha-myosin heavy chain mRNA via the 3′ untranslated region mediated by an initial block in translation.

Isolation and characterization of full-length cDNA clones for human alpha-, beta-, and gamma-actin mRNAs: skeletal but not cytoplasmic actins have an amino-terminal cysteine that is subsequently removed

1983 ◽  
Vol 3 (5) ◽  
pp. 787-795
Author(s):  
P Gunning ◽  
P Ponte ◽  
H Okayama ◽  
J Engel ◽  
H Blau ◽  
...  
Keyword(s):  
Cdna Library ◽  
Untranslated Region ◽  
Human Muscle ◽  
Full Length ◽  
Cdna Clones ◽  
Actin Gene ◽  
Coding Region ◽  
Base Pairs ◽  
Methionine Codon ◽  
Alpha Actin

cDNA clones encoding three classes of human actins have been isolated and characterized. The first two classes (gamma and beta, cytoplasmic actins) were obtained from a cDNA library constructed from simian virus 40-transformed human fibroblast mRNA, and the third class (alpha, muscle actin) was obtained from a cDNA library constructed from adult human muscle mRNA. A new approach was developed to enrich for full-length cDNAs. The human fibroblast cDNA plasmid library was linearized with restriction enzymes that did not cut the inserts of interest; it was then size-fractionated on gels, and the chimeric molecules of optimal length were selected for retransformation of bacteria. When the resulting clones were screened for actin-coding sequences it was found that some full-length cDNAs were enriched as much as 50- to 100-fold relative to the original frequency of full-length clones in the total library. Two types of clones were distinguished. One of these clones encodes gamma actin and contains 100 base pairs of 5' untranslated region, the entire protein coding region, and the 3' untranslated region. The second class encodes beta actin, and the longest such clone contains 45 base pairs of 5' untranslated region plus the remainder of the mRNA extending to the polyadenylic acid tail. A third class, obtained from the human muscle cDNA library, encodes alpha actin and contains 100 base pairs of 5' untranslated region, the entire coding region, and the 3' untranslated region. Analysis of the DNA sequences of the 5' end of the clones demonstrated that although beta- and gamma-actin genes start with a methionine codon (MET-Asp-Asp-Asp and MET-Glu-Glu-Glu, respectively), the alpha-actin gene starts with a methionine codon followed by a cysteine codon (MET-CYS-Asp-Glu-Asp-Glu). Since no known actin proteins start with a cysteine, it is likely that post-translational removal of cysteine in addition to methionine accompanies alpha-actin synthesis but not beta- and gamma-actin synthesis. This observation has interesting implications both for actin function and actin gene regulation and evolution.

scholarly journals Characterization of bovine tracheobronchial phenol sulphotransferase cDNA and detection of mRNA regulation by cortisol

1995 ◽  
Vol 311 (1) ◽  
pp. 209-217 ◽  
Author(s):  
S J Schauss ◽  
T Henry ◽  
R Palmatier ◽  
L Halvorson ◽  
R Dannenbring ◽  
...  
Keyword(s):  
Epithelial Cell ◽  
Cdna Library ◽  
Bronchial Epithelial Cell ◽  
Mrna Levels ◽  
Dependent Manner ◽  
Coding Region ◽  
Culture Model ◽  
Steady State Levels ◽  
Tracheal Epithelial ◽  
High Level

Phenol sulphotransferases esterify both endogenous and foreign hydroxylated aromatic compounds with sulphate. Since these enzymes participate in both hormone and drug metabolism, elucidating their regulation at both the enzymic and molecular levels may provide new understanding in several metabolic pathways. The primary structure of a bovine phenol sulphotransferase has been determined by isolation of the corresponding cDNA. Two partial bovine cDNAs were first isolated by probing a tracheal epithelial cell lambda gt11 cDNA library with a rat phenol sulphotransferase cDNA. These clones provided the sequences of the 5′ and 3′ ends of the predicted coding region. A contiguous cDNA was subsequently isolated by PCR using 5′ and 3′ oligonucleotide primers and the cDNA library as the template. The sequence of the resulting approx. 1 kbp cDNA predicted an amino acid sequence that included sequences determined for several tryptic peptides of the purified protein. Antiserum directed to a synthetic N-terminal peptide predicted by the cDNA sequence showed reactivity with the purified enzyme. High-level Trc-promoter-driven expression of the recombinant bovine enzyme was achieved in Escherichia coli. The bovine cDNA was used to determine relative steady-state levels of phenol sulphotransferase transcripts in bovine lung tissues; distal lung parenchymal RNA levels were 6-10-fold greater than those in tracheobronchial epithelium. Using a bronchial epithelial cell culture model, however, cortisol was observed to increase mRNA levels by 5-fold in both a dose- and time-dependent manner; this corresponds to previously reported glucocorticoid stimulation of phenol sulphotransferase activity in this system [Beckmann, Illig and Bartzatt (1994) J. Cell Physiol. 160, 603-610].

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