Effect of Environmental Stressors on the mRNA Expression of Ecdysone Cascade Genes in Chironomus Riparius.

Abstract Chemical compounds produced by humans are continuously reaching the environment. In this work, we characterised the expression patterns of important endocrine-related genes involved in the ecdysone pathway in the fourth larval instar of the model species Chironomus riparius after exposure to three chemicals: ethinyl oestradiol (EE), nonylphenol (NP) and bis(tributyltin) oxide (TBTO). We used real-time PCR to analyse the gene expression levels of: ecdysone receptor (EcR) and ultraspiracle (usp), two genes that encode the dimerising partners of the functional ecdysone receptor; the orphan receptor ERR (oestrogen-related receptor), with an unknown function in invertebrates; and E74, an early response gene induced by ecdysteroids. We estimated the bioaccumulation potential, bioavailability and physicochemical properties of these chemicals, together with a number of other exogenous agents known to interfere with the hormonal system. We also provide a review of previous transcriptional studies showing the effect of all these chemicals on ecdysone cascade genes. This analysis provides useful data for future ecotoxicological studies involving invertebrate species.

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Effect of environmental stressors on the mRNA expression of ecdysone cascade genes in Chironomus riparius

Environmental Science and Pollution Research ◽

10.1007/s11356-021-16339-3 ◽

2021 ◽

Author(s):

Mercedes de la Fuente ◽

Raquel Martín Folgar ◽

Pedro Martínez-Paz ◽

Estrella Cortés ◽

José Luis Martínez-Guitarte ◽

...

Keyword(s):

Larval Instar ◽

Expression Patterns ◽

Endocrine Disrupting Chemicals ◽

Early Response ◽

Orphan Receptor ◽

Ecdysone Receptor ◽

Endocrine Disrupting ◽

Exogenous Agents ◽

Hormonal System ◽

Gene Expression Levels

Abstract Chemical compounds produced by humans are continuously reaching the environment. In this work, we characterised the expression patterns of important endocrine-related genes involved in the ecdysone pathway in the fourth larval instar of the model species Chironomus riparius after exposure to three chemicals: ethinyl oestradiol (EE), nonylphenol (NP) and bis(tributyltin) oxide (TBTO). We used real-time PCR to analyse the gene expression levels of ecdysone receptor (EcR) and ultraspiracle (usp), two genes that encode the dimerising partners of the functional ecdysone receptor; the orphan receptor ERR (oestrogen-related receptor), with an unknown function in invertebrates; and E74, an early response gene induced by ecdysteroids. We estimated the bioaccumulation potential, bioavailability and physicochemical properties of these chemicals, together with a number of other exogenous agents known to interfere with the hormonal system. We also provide a review of previous transcriptional studies showing the effect of all these chemicals on ecdysone cascade genes. This analysis provides useful data for future ecotoxicological studies involving invertebrate species. Capsule Changes in transcriptional activities of EcR, E74, usp and ERR genes after exposure to endocrine-disrupting chemicals would be useful as molecular bioindicators of endocrine disruption in Chironomus riparius.

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The Orphan Nuclear Receptor 4A1: A Potential New Therapeutic Target for Metabolic Diseases

Journal of Diabetes Research ◽

10.1155/2018/9363461 ◽

2018 ◽

Vol 2018 ◽

pp. 1-10 ◽

Cited By ~ 5

Author(s):

Lei Zhang ◽

Qun Wang ◽

Wen Liu ◽

Fangyan Liu ◽

Ailing Ji ◽

...

Keyword(s):

Skeletal Muscle ◽

Lipid Metabolism ◽

Nuclear Receptor ◽

Metabolic Diseases ◽

Early Response ◽

Orphan Receptor ◽

Special Focus ◽

Orphan Nuclear Receptor ◽

Physiological Functions ◽

The Impact

Orphan nuclear receptor 4A1 (NR4A1) is a transcriptional factor of the nuclear orphan receptor (NR4A) superfamily that has sparked interest across different research fields in recent years. Several studies have demonstrated that ligand-independent NR4A1 is an immediate-early response gene and the protein product is rapidly induced by a variety of stimuli. Hyperfunction or dysfunction of NR4A1 is implicated in various metabolic processes, including carbohydrate metabolism, lipid metabolism, and energy balance, in major metabolic tissues, such as liver, skeletal muscle, pancreatic tissues, and adipose tissues. No endogenous ligands for NR4A1 have been identified, but numerous compounds that bind and activate or inactivate nuclear NR4A1 or induce cytoplasmic localization of NR4A1 have been identified. This review summarizes recent advances in our understanding of the molecular biology and physiological functions of NR4A1. And we focus on the physiological functions of NR4A1 receptor to the development of the metabolic diseases, with a special focus on the impact on carbohydrate and lipid metabolism in skeletal muscle, liver, adipose tissue, and islet.

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The Efficiency of Terpenes Extracts of Eucalyptus Camaldulensis Seed to control Larval Stage of Callosobruchus maculates (Coleoptera:Bruchidae)

Baghdad Science Journal ◽

10.21123/bsj.13.4.625-630 ◽

2016 ◽

Vol 13 (4) ◽

pp. 625-630

Author(s):

Baghdad Science Journal

Keyword(s):

Mortality Rate ◽

Larval Stage ◽

Germination Rate ◽

Larval Instar ◽

Eucalyptus Camaldulensis ◽

Adult Emergence ◽

Control Treatment ◽

Fourth Larval Instar ◽

Cowpea Seed

The current study has beenconduced to evaluate the effect of extracted crude terpens at the concentrations of 6,8% of seeds of Eucalyptuscamaldulensison the 4th larval instar oftheCallosobruchusmaculates and the percentage of the cowpea seed germination.The Results showed that the terpens extract of the concentration of 8% increases the mortality rate of the fourth larval instar and it reach to 63.3%, and then decrease of to 26.6,20% at concentration of 6%and forcontrol treatment respectively The percentage of adult emergence reduces to 0% at the concentration of 8% compared with control treatment in which it reach to 66.6%. The extraction atbothconcentrations 6,8% does not affect the germination rate

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Spermatogenesis and Testis Development Are Normal in Mice Lacking Testicular Orphan Nuclear Receptor 2

Molecular and Cellular Biology ◽

10.1128/mcb.22.13.4661-4666.2002 ◽

2002 ◽

Vol 22 (13) ◽

pp. 4661-4666 ◽

Cited By ~ 30

Author(s):

Chih-Rong Shyr ◽

Loretta L. Collins ◽

Xiao-Min Mu ◽

Kenneth A. Platt ◽

Chawnshang Chang

Keyword(s):

Protein Expression ◽

Nuclear Receptor ◽

Expression Patterns ◽

Orphan Receptor ◽

Orphan Nuclear Receptor ◽

Male Mice ◽

Orphan Nuclear Receptors ◽

Nuclear Receptor Superfamily ◽

Testis Development

ABSTRACT Early in vitro cell culture studies suggested that testicular orphan nuclear receptor 2 (TR2), a member of the nuclear receptor superfamily, may play important roles in the control of several pathways including retinoic acids, vitamin D, thyroid hormones, and ciliary neurotrophic factor. Here we report the surprising results showing that mice lacking TR2 are viable and have no serious developmental defects. Male mice lacking TR2 have functional testes, including normal sperm number and motility, and both male and female mice lacking TR2 are fertile. In heterozygous TR2+/− male mice we found that β-galactosidase, the indicator of TR2 protein expression, was first detected at the age of 3 weeks and its expression pattern was restricted mainly in the spermatocytes and round spermatids. These protein expression patterns were further confirmed with Northern blot analysis of TR2 mRNA expression. Together, results from TR2-knockout mice suggest that TR2 may not play essential roles in spermatogenesis and normal testis development, function, and maintenance. Alternatively, the roles of TR2 may be redundant and could be played by other close members of the nuclear receptor superfamily such as testicular orphan receptor 4 (TR4) or unidentified orphan receptors that share many similar functions with TR2. Further studies with double knockouts of both orphan nuclear receptors, TR2 and TR4, may reveal their real physiological roles.

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Carbamate and organophosphate resistance in Culex pipiens L. (Diptera: Culicidae) in southern France and the significance of Est-3A

Bulletin of Entomological Research ◽

10.1017/s000748530001405x ◽

1984 ◽

Vol 74 (4) ◽

pp. 677-687 ◽

Cited By ~ 8

Author(s):

R. J. Wood ◽

N. Pasteur ◽

G. Sinégre

Keyword(s):

Culex Pipiens ◽

Larval Instar ◽

Piperonyl Butoxide ◽

Southern France ◽

Organophosphate Resistance ◽

Metabolic Component ◽

Carbamate Insecticides ◽

Fourth Larval Instar ◽

Resistant Strains ◽

Tributyl Phosphorotrithioate

AbstractThree French strains of Culex pipiens L. were compared at the fourth larval instar for tolerance to organophosphate and carbamate insecticides, with and without the addition of synergists (the oxidase inhibitors piperonyl butoxide and CGA 84708) (a propynyl compound) and the carboxylesterase inhibitors triphenyl phosphate (TPP) and S,S,S-tributyl phosphorotrithioate (TBPT). The S54 strain was resistant to all the organophosphates tested (chlorpyrifos, malathion, monocrotophos and profenofos) compared to the susceptible LA VIS strain but only slightly tolerant to the two carbamates (carbaryl and naphthyl phenylcarbamate). The MAURIN strain was resistant to all the insecticides, including the carbamates, at a higher level. The action of chlorpyrifos and malathion on S54 was very strongly synergised by TBPT, less strongly by TPP and not at all by piperonyl butoxide. In fact, resistance was enhanced by piperonyl butoxide, as was resistance to monocrotophos and profenofos by CGA 84708. No synergist had much effect on the MAURIN strain, although TPP slightly increased the toxicity of malathion, and piperonyl butoxide and CGA 84708 slightly increased the toxicity of carbaryl. The toxic effect of carbaryl was also increased by the addition of extra acetone. Electrophoretic studies showed that the carboxylesterase enzyme coded by gene Est-20.64 (which is in linkage disequilibrium withEst-3A and acts as a marker for it) was absent from LA VIS but present in the resistant strains; but, whereas S54 was monomorphic for the gene, MAURIN was polymorphic (frequency 0·5). It is concluded that organophosphate resistance in S54 was due to detoxification by carboxylesterase wherease organophosphate and carbamate resistance in MAURIN had a strong non-metabolic component, possibly an insensitive acetylcholinesterase.

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The hemolymph titer of juvenile hormone binding protein and binding sites during the fourth larval instar of Manduca sexta

General and Comparative Endocrinology ◽

10.1016/0016-6480(78)90165-x ◽

1978 ◽

Vol 35 (1) ◽

pp. 27-34 ◽

Cited By ~ 36

Author(s):

Walter Goodman ◽

Lawrence I. Gilbert

Keyword(s):

Juvenile Hormone ◽

Manduca Sexta ◽

Binding Sites ◽

Binding Protein ◽

Larval Instar ◽

Hormone Binding ◽

Juvenile Hormone Binding Protein ◽

Fourth Larval Instar ◽

Hormone Binding Protein

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Correlation of messenger RNA expression patterns of ERCC1, TS, EGFR, and VEGFR2 with KRAS and BRAF mutational status in advanced colorectal cancer: Implications for targeted therapies.

Journal of Clinical Oncology ◽

10.1200/jco.2013.31.4_suppl.383 ◽

2013 ◽

Vol 31 (4_suppl) ◽

pp. 383-383

Author(s):

Martin K. H. Maus ◽

Craig Stephens ◽

Stephanie H. Astrow ◽

Peter Philipp Grimminger ◽

Dongyun Yang ◽

...

Keyword(s):

Gene Expression ◽

Colorectal Cancer ◽

Mrna Expression ◽

Advanced Colorectal Cancer ◽

Expression Patterns ◽

Mrna Levels ◽

Expression Levels ◽

Mutational Status ◽

Mrna Expression Levels ◽

Gene Expression Levels

383 Background: Gene expression levels of ERCC1, TS, EGFR and VEGFR2 may have predictive value for the personalized use of standard chemotherapeutics as well as agents targeting the EGFR and VEGF pathways and the efficacy of EGFR directed monoclonal antibodies like panitumumab and cetuximab has been confirmed to be dependent on wt KRAS and wt BRAF in patients with advanced colorectal cancer. We investigated the correlations between KRAS/BRAF mutational status and the mRNA expression levels of these genes. Methods: Formalin-fixed paraffin-embedded tumor specimens from 600 patients with advanced colorectal adenocarcinoma were microdissected and DNA and RNA was extracted. Specifically designed primers and probes were used to detect 7 different base substitutions in codon 12 and 13 of KRAS, V600E mutations in BRAF and the expression levels of ERCC1, TS, EGFR and VEGFR2 by RT-PCR. Results: Mt KRAS tumors had significantly lower TS and EGFR gene expression levels compared with wt KRAS (p<0,001), whereas mt BRAF tumors showed significantly increased TS and EGFR mRNA levels compared to wt BRAF (p<0,001). Mt BRAF tumors showed significantly higher mRNA levels than mt KRAS tumors (p<0,001). ERCC1 and VEGFR2 mRNA levels were significantly down-regulated in mt KRAS specimen (p<0,001), but showed no significant correlation with BRAF mutational status. Conclusions: KRAS and BRAF mutations are associated with opposite mRNA expression levels for TS and EGFR. Recently, resistance to BRAF inhibition in mt BRAF colorectal tumors has been shown in preclinical models to be associated with up-regulation of EGFR. Our data suggests that BRAF mutants are associated with high EGFR levels at the time of diagnosis, and not necessarily part of an acquired mechanism of resistance. Significantly lower mRNA expression levels of VEGFR2 in mt KRAS tumors may explain lower response to angiogenesis inhibition seen in the TML study.

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Distinct expression patterns and biological activities of two isoforms of the mouse orphan receptor TR2

Journal of Endocrinology ◽

10.1677/joe.0.1520245 ◽

1997 ◽

Vol 152 (2) ◽

pp. 245-255 ◽

Cited By ~ 23

Author(s):

C-H Lee ◽

L Chang ◽

L-N Wei

Keyword(s):

Germ Cell ◽

Cell Line ◽

Germ Cells ◽

Biological Activities ◽

Expression System ◽

Expression Patterns ◽

Orphan Receptor ◽

Testicular Cell ◽

Prokaryotic Expression System ◽

Orphan Receptor Tr2

Abstract An alternatively spliced variant of a testis-specific nuclear orphan receptor TR2-11 was identified and designated as TR2-11-t. As a result of retaining intron 5 of this gene, TR2-11-t mRNA encoded a truncated receptor with the complete ligand-binding domain deleted. Protein expression of both isoforms was confirmed using a prokaryotic expression system. In the mouse, the expression of the two TR2 isoforms was elevated in the testis with distinct profiles beginning at puberty. TR2-11 expression increased at postnatal day 18, peaked between day 20 and day 24 and remained at high levels throughout adulthood, whereas TR2-11-t expression was elevated transiently at postnatal day 24. Among separated primary germ cells and established testicular cell lines, TR2-11 was expressed highly in meiotic and postmeiotic germ cells and weakly in a Leydig cell line and a germ cell line, but not expressed in a Sertoli cell line. In contrast, TR2-11-t was expressed at a much lower level in all the testicular cell types examined. In adult testes blocked at germ cell development by vitamin A depletion or hypophysectomy, TR2-11 expression was dramatically reduced whereas TR2-11-t was highly elevated. Based upon the RNA expression patterns of these isoforms, it was suggested that TR2-11 was specific to meiotic and postmeiotic germ cells whereas TR2-11-t was enriched in early germ cell populations such as premeiotic cells. The biological activities of TR2-11 and TR2-11-t on a direct repeat 5-type retinoic acid (RA) response element (RARE)-containing reporter gene was examined in Cos cells. TR2-11 repressed RA induction of this reporter whereas TR2-11-t enhanced RA induction of the same reporter, and the opposite biological effects of these isoforms were dose-dependent. Gel-shift experiments provided evidence for a direct interaction of TR2-11, but not TR2-11-t, with DNA fragments containing this RARE. Opposite roles of TR2-11 and TR2-11-t on RA induction of promoters containing this particular RARE are suggested. Journal of Endocrinology (1997) 152, 245–255

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