Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

---

Query: EC:2.7.7.49 (reverse transcriptase)
31,746 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The mouse corticotropin-releasing factor (CRF) type 2a receptor (CRF2(a)) splice variant was cloned by a PCR-based approach. The corresponding cDNA was found to encode a 411-amino acid polypeptide with highest sequence homology to the rat CRF2(a) receptor. By semiquantitative reverse transcriptase PCR (RT-PCR) analysis, the CRF2(b) mRNA was mainly found in the heart and skeletal muscle with only low level expression in the brain. In contrast, CRF2(a) mRNA was restricted to the brain with major expression sites in the cortex, hippocampus, hypothalamus and telencephalon. Binding and cyclic AMP stimulation studies showed a similar ligand selective profile for both mCRF2 receptor splice variants. A notable exception however, was urotensin I which displayed a approximately 3-fold higher affinity for the CRF2(a) receptor and also stimulated cyclic AMP production in mCRF2(a)-transfected cells with a approximately 3-fold higher potency than in mCRF2(b)-transfected cells. These data show that the mouse like other mammalian species expresses two ligand-selective CRF2 receptor splice variants and that the mCRF2(a) receptor is the predominant central CRF2 receptor in the mouse.
...
PMID:Molecular cloning and functional expression of the mouse CRF2(a) receptor splice variant. 1525 78

Urocortin 3 (Ucn 3)/stresscopin (SCP) is a novel peptide of the corticotropin-releasing factor (CRF) family and is a specific ligand for the CRF type 2 receptor. In the present study, we studied expression of Ucn3/SCP in the normal adrenal and adrenal tumors by radioimmunoassay and reverse transcriptase-polymerase chain reaction (RT-PCR). High concentrations of immunoreactive (IR)-Ucn3 were present in the normal portions of adrenal glands (4.2+/-0.51 pmol/g wet weight, mean+/-S.E.M., n = 14), and the levels were higher than those in the brain. IR-Ucn3 was also detected in the tumor tissues of aldosterone-secreting adenomas (6.2+/-0.6 pmol/g wet weight, n = 10), cortisol-secreting adenomas (5.0+/-1.2 pmol/g wet weight, n = 4), and pheochromocytomas (1.9+/-0.4 pmol/g wet weight, n = 7). Reverse phase high performance liquid chromatography showed that IR-Ucn3 in normal portions of adrenal glands and aldosterone-secreting adenomas was eluted mainly in the positions of Ucn3 and SCP with several minor peaks eluting earlier. The RT-PCR showed expression of Ucn3 mRNA in normal portions of adrenal gland (positive ratio; 4/4), aldosterone-secreting adenomas (3/4), cortisol-secreting adenomas (1/3) and pheochromocytomas (6/7). These findings indicate that Ucn3 is produced in normal adrenal and adrenal tumors (both adrenocortical tumors and pheochromocytomas), and suggest that Ucn3 acts as an autocrine or paracrine regulator in normal adrenal and adrenal tumors.
...
PMID:Expression of urocortin 3/stresscopin in human adrenal glands and adrenal tumors. 1609 56

Corticotropin-releasing hormone (CRH) is secreted under stress and regulates the hypothalamic-pituitary-adrenal (HPA) axis; it is also secreted outside the brain where it exerts proinflammatory effects, possibly through mast cell activation. Mast cells are necessary for allergic reactions, but are increasingly implicated in acquired immunity and inflammatory diseases worsened by stress. Acute stress and intradermal CRH induced murine skin mast cell activation and increased vascular permeability that was absent in W/W(v) mast cell deficient mice. The presence of functional CRH receptors (CRH-R) was recently reported on human mast cells. Here, we studied the expression of CRH-R1 and CRH-R2 by semiquantitative reverse transcriptase-polymerase chain reaction (RT-PCR) and fluorescent immunocytochemistry in human umbilical cord blood-derived cultured mast cells (hCBMCs) treated with Interleukin (IL)-1, IL-4 or lipopolysaccharide (LPS). Ten week-old hCBMCs cultured in the presence of Stem cell factor (SCF) and IL-6 were positive for both CRH-R1 and CRH-R2. However, the expression of only CRH-R2 mRNA and protein was induced by priming hCBMCs with IL-4 for the last three weeks of culture. Further analysis of the CR-H R2 mRNA expression showed that addition of IL-1 or LPS for 6 h increased only CRH-R2 gene expression. CRH had negligible effect on IL-6 secretion from non-primed hCBMCs, but induced release from IL-4 primed cells. Interestingly, LPS alone increased IL-6 release in non-primed cells, but lost this effect in primed cells. These results further implicate mast cells and CRH in either initiating or potentiating inflammatory diseases, especially those affected by stress.
...
PMID:Regulation of corticotropin-releasing hormone receptor-2 expression in human cord blood-derived cultured mast cells. 1632 28

Urocortin (UCN) is a 40-amino acid neuropeptide sharing 45% sequence homology with corticotropin-releasing factor (CRF). The human endometrium expresses both UCN and CRF, and CRF/UCN receptors type-1 (CRF-R1) and -2 (CRF-R2). CRF-R1 activation inhibits cell growth and proliferation of a tumor cell line derived from the human endometrium, and the UCN signaling pathway has been implicated in tumorigenesis of several tissues. Therefore, we investigated whether UCN mRNA and peptide are expressed by human endometrial adenocarcinoma, and whether their expression changes compared to controls. Samples of well (grade 1; n = 6 endometrioid adenocarcinoma, of whom n = 1 with squamous differentiation, and n = 1 clear-cell carcinoma) and poorly differentiated (grade 3; n = 3 endometrioid adenocarcinoma) endometrial adenocarcinoma were collected from nine women (age range 61-79 years) enrolled at the time of diagnosis. Healthy endometrium was collected from postmenopausal women (controls; n = 13; age range 64-78 years), who underwent hysterectomy for uterine prolapse. Immunohistochemistry was used to evaluate cellular UCN localization, with the intensity of immunostaining scored on a subjective scale. Quantitative real-time reverse transcriptase (RT)-PCR analysis was used to estimate mRNA expression changes and restriction analysis was used to confirm PCR products identity. UCN mRNA expression was significantly reduced (P < 0.0001) in endometrial adenocarcinoma than in healthy controls. Immunoreactive UCN was found in luminal and glandular epithelial cells in healthy, but not in neoplastic samples. UCN mRNA and peptide expressions are decreased in endometrial adenocarcinoma. These data and the evidence that endometrial cancer expresses UCN receptors and UCN is involved in tumorigenesis of several tissues together suggest a role for UCN in endometrial tumoral cell growth and proliferation.
...
PMID:Urocortin expression is downregulated in human endometrial carcinoma. 1683 14

Urocortin II and urocortin III are recently identified corticotropin-releasing factor-related neuropeptides, and their endometrial expression throughout the menstrual cycle and in early pregnancy was evaluated in the present study by semiquantitative reverse transcriptase polymerase chain reaction and immunohistochemistry. The endometrial expression of urocortin II mRNA was significantly (P<.01) higher in the early proliferative phase of the menstrual cycle than in other phases and maternal decidua (MD), whereas that of urocortin III mRNA was higher (P<.01) in MD than in all other endometrial samples. Both peptides were immunolocalized in epithelial, stromal, and endothelial cells.
...
PMID:Human endometrium expresses urocortin II and III messenger RNA and peptides. 1707 39

The caudal neurosecretory system (CNSS) of the euryhaline flounder Platichthys flesus has suggested roles in osmoregulatory, reproductive and nutritional adaptation, as fish migrate between seawater (winter) and brackish/freshwater (summer) environments. This study examined seasonal changes in mRNA expression profile of functionally important genes in the CNSS. cDNAs encoding neuropeptides, receptors and ion channels were cloned by reverse transcriptase polymerase chain reaction (RT-PCR) and screening of a flounder CNSS cDNA library. The expression profile of cloned genes was determined by real-time RT-PCR at 2-month intervals throughout the year in CNSS from seawater-adapted fish. Plasma cortisol (measured by radioimmunoassay) showed a peak in April, the time of spawning. Expression levels of mRNA for peptides urotensins I and II (UI, UII) and corticotropin releasing factor (CRF) all showed a seasonal cycle, with lowest expression in April and highest in August-October. The expression of CRF2(UI), UT(UII) and CRF1 receptors was not correlated with corresponding peptide expression. Receptors for potential neuromodulators of CNSS activity also displayed a seasonal mRNA expression profile. Glucocorticoid, 5-hydroxytryptamine, kappa-opioid and glutamate receptor expression peaked around April, suggesting that modulation of electrical activity of the neurosecretory Dahlgren cells is of particular importance at this time. Expression of mRNA for L-type Ca(2+) and Ca-activated K(+) channels was lower during the summer months. These channels underlie electrical bursting activity in Dahlgren cells. Ion channel mRNA expression was also lower in CNSS from flounder fully adapted to freshwater as opposed to seawater, consistent with previously reported observations of reduced bursting activity in Dahlgren cells from freshwater-adapted CNSS. These findings support the hypothesis that the CNSS is functionally reprogrammed to cope with changes in physiological challenge as fish migrate between sea and estuaries in winter and spring.
...
PMID:Seasonal changes in peptide, receptor and ion channel mRNA expression in the caudal neurosecretory system of the European flounder (Platichthys flesus). 1756 41

High-frequency/low-energy gastric electrical stimulation (GES) is an efficient therapy to treat gastric emptying-related disorders but its mechanism of action remains poorly understood. We aimed to assess the effects of high-frequency/low-energy GES on corticotropin-releasing factor (CRF)-producing neurons in the paraventricular nucleus of the hypothalamus (PVN), which are involved in gastric ileus induced by laparotomy. Two electrodes were implanted in the rat gastric antrum during laparotomy, then stimulation (amplitude: 2 mA; pulse duration 330 micros; frequency: 2 Hz; 1 min ON/2 min OFF) or sham stimulation (control group) were applied. Using immunohistochemistry, the number of c-Fos protein-expressing neurons (c-Fos protein-immunoreactive cells, Fos-IR) was quantified in the PVN after 1 h of stimulation. The number of neurons expressing simultaneously c-Fos protein and CRF mRNA was measured by means of immunocytochemistry combined with in situ hybridization. Finally, c-Fos and CRF mRNA levels in the hypothalamus were determined by in situ hybridization or quantitative reverse transcriptase-polymerase chain reaction. Fos-IR in the PVN was significantly decreased 1 h after GES (P<0.05) but was not affected by sub-diaphragmatic vagotomy. The number of neurons containing c-Fos protein and CRF mRNA was lower in the GES group compared with the control group (P<0.05). In addition, c-Fos and CRF mRNA levels in the PVN were significantly decreased by GES (P<or=0.05). It is concluded that acute GES reduces the number of CRF-producing neurons and decreases CRF expression in the PVN during post-operative gastric ileus.
...
PMID:Gastric electrical stimulation modulates hypothalamic corticotropin-releasing factor-producing neurons during post-operative ileus in rat. 1769 31

Intraperitoneal (i.p.) corticotropin releasing factor (CRF) induced a CRF(1) receptor-dependent stimulation of myenteric neurons and motility in the rat proximal colon. We characterize the colonic enteric nervous system response to CRF in conscious rats. Laser capture microdissection combined with reverse transcriptase polymerase chain reaction (RT-PCR) and immunohistochemistry in longitudinal muscle myenteric plexus whole-mount colonic preparations revealed CRF(1) receptor expression in myenteric neurons. CRF (i.p., 10 microg kg(-1)) induced Fos immunoreactivity (IR) (cells per ganglion) selectively in myenteric plexus of proximal (18.3 +/- 2.4 vs vehicle: 0.0 +/- 0.0) and distal colon (16.8 +/- 1.2 vs vehicle: 0.0 +/- 0.0), but not in that of gastric corpus, antrum, duodenum, jejunum and ileum. The selective CRF(1) agonist, stressin(1)-A (i.p., 10 microg kg(-1)) also induced Fos IR in myenteric but not in submucosal plexus of the proximal and distal colon. Fos IR induced by CRF was located in 55 +/- 1.9% and 53 +/- 5.1% of CRF(1) receptor-IR myenteric neurons and in 44 +/- 2.8% and 40 +/- 3.9% of cholinergic neurons with Dogiel type I morphology, and in 20 +/- 1.6% and 80 +/- 3.3% of nitrergic neurons in proximal and distal colon respectively. CRF and stressin(1)-A elicit defecation and diarrhoea. These data support that one mechanism through which peripherally injected CRF ligands stimulate colonic function involves a direct action on colonic cholinergic and nitrergic myenteric neurons expressing CRF(1) receptor.
...
PMID:Peripheral corticotropin releasing factor (CRF) and a novel CRF1 receptor agonist, stressin1-A activate CRF1 receptor expressing cholinergic and nitrergic myenteric neurons selectively in the colon of conscious rats. 1797 38

We previously showed that betaxolol, a selective beta(1)-adrenergic receptor antagonist, administered during early phases of cocaine abstinence, ameliorated withdrawal-induced anxiety and blocked increases in amygdalar beta(1)-adrenergic receptor expression in rats. Here, we report the efficacy of betaxolol in reducing increases in gene expression of amygdalar corticotropin-releasing factor (CRF), a peptide known to be involved in mediating 'anxiety-like' behaviors during initial phases of cocaine abstinence. We also demonstrate attenuation of an amygdalar beta(1)-adrenergic receptor-mediated cell-signaling pathway following this treatment. Male rats were administered betaxolol at 24 and 44 h following chronic cocaine administration. Animals were euthanized at the 48-h time point and the amygdala was microdissected and processed for quantitative reverse transcriptase-polymerase chain reaction and/or western blot analysis. Results showed that betaxolol treatment during early cocaine withdrawal attenuated increases in amygdalar CRF gene expression and cyclic adenosine monophosphate-dependent protein kinase regulatory and catalytic subunit (nuclear fraction) protein expression. Our data also reveal that beta(1)-adrenergic receptors are on amygdalar neurons, which are immunoreactive for CRF. The present findings suggest that the efficacy of betaxolol treatment on cocaine withdrawal-induced anxiety may be related, in part, to its effect on amygdalar beta(1)-adrenergic receptor, modulation of its downstream cell-signaling elements and CRF gene expression.
...
PMID:Evidence for beta1-adrenergic receptor involvement in amygdalar corticotropin-releasing factor gene expression: implications for cocaine withdrawal. 1859 87

Corticotropin-releasing hormone (CRH) plays a central role in controlling stress response. In this study, we aimed to identify the regulatory effect of estrogen receptor (ER) on CRH and the underlying mechanism. We investigated the regulation of CRH mRNA in the BE(2)-C cell line, a human neuroblastoma cell line which express endogenous CRH. Quantitative reverse transcriptase-polymerase chain reactions showed that in the presence of estradiol overexpressing ER alpha or ER beta in BE(2)-C cells increased the transcription of CRH. Chromatin immunoprecipitation assays in this cell line also showed that both ER alpha and ER beta can be recruited to the CRH promoter with the treatment of estradiol. However, electrophoretic mobility shift assays did not show direct binding between estrogen receptors and two estrogen response elements (ERE) half sites in the CRH promoter. To clarify the regulatory mechanism, site-directed mutagenesis and reporter gene assay in the CHO cell line were used. When the ERE half sites and the cAMP regulatory element (CRE) in the CRH promoter were disrupted, ER-mediated up-regulation of CRH promoter activity reduced. Between the two ERE half sites studied, the -316 ERE half site contributed more to the constitutive CRH expression induced by ER. In summary, our results confirm the stimulation of ER alpha and ER beta on CRH expression and demonstrate the important roles of the ERE half sites and CRE for the action of ER alpha and ER beta.
...
PMID:Estrogen receptor-alpha and -beta regulate the human corticotropin-releasing hormone gene through similar pathways. 1859 42


<< Previous 1 2 3 Next >>

---