Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:4.6.1.2 (guanylate cyclase)
 8,497 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Soluble guanylyl cyclase (sGC) is a cytosolic enzyme producing the intracellular messenger cyclic guanosine monophosphate (cGMP) on activation with nitric oxide (NO). sGC is an obligatory heterodimer composed of alpha and beta subunits. We investigated human beta1 sGC transcriptional regulation in BE2 human neuroblastoma cells. The 5' upstream region of the beta1 sGC gene was isolated and analyzed for promoter activity by using luciferase reporter constructs. The transcriptional start site of the beta1 sGC gene in BE2 cells was identified. The functional significance of consensus transcriptional factor binding sites proximal to the transcriptional start site was investigated by site deletions in the 800-bp promoter fragment. The elimination of CCAAT-binding factor (CBF) and growth factor independence 1 (GFI1) binding cores significantly diminished whereas deletion of the NF1 core elevated the transcription. Electrophoretic mobility-shift assay (EMSA) and Western analysis of proteins bound to biotinated EMSA probes confirmed the interaction of GFI1, CBF, and NF1 factors with the beta1 sGC promoter. Treatment of BE2 cells with genistein, known to inhibit the CBF binding to DNA, significantly reduced protein levels of beta1 sGC by inhibiting transcription. In summary, our study represents an analysis of the human beta1 sGC promoter regulation in human neuroblastoma BE2 cells and identifies CBF as a critically important factor in beta1 sGC expression.
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PMID:CCAAT-binding factor regulates expression of the beta1 subunit of soluble guanylyl cyclase gene in the BE2 human neuroblastoma cell line. 1450 8

Soluble guanylyl cyclase is a cytosolic enzyme which catalyzes conversion of GTP to the second messenger cyclic GMP. The transcriptional regulation at the promoter levels of four soluble guanylyl cyclase subunits, termed alpha1, alpha2, beta1, and beta2, is largely unknown. In this study, we identified the transcription start site of alpha1-soluble guanylyl cyclase gene in rat pituitary cells and cloned the 3.5 kb 5'-promoter. Sequence analysis of this TATA-less promoter revealed the presence of several putative-binding sites for transcriptional factors, including CCAAT site at -41 to -32 and Sp1 site at -34 to -24. Transfection of pituitary cells with constructs of variable lengths confirmed the relevance of different promoter regions in the control of transcriptional activity. Among them, the -49 to + 156 region was critical for basal transcriptional activity. Electrophoretic mobility shift assay using nuclear proteins extracted from normal and immortalized pituitary cells indicated that the CCAAT/Sp1 site within the -49 to + 156 region was able to specifically interact with CCAAT-binding factor and Sp1. These two sites were partly overlapped and both of them conferred stimulatory effects. The in vivo recruitment of CCAAT-binding factor and Sp1 was confirmed by chromatin immunoprecipitation. These results indicate that the composite CCAAT/Sp1 cis-element contributes to the expression of alpha1-sGC subunit in resting pituitary cells.
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PMID:Molecular cloning and characterization of alpha1-soluble guanylyl cyclase gene promoter in rat pituitary cells. 1717 90

Soluble guanylyl cyclase (sGC) is the principal receptor for NO and plays a ubiquitous role in regulating cellular function. This is exemplified in the cardiovascular system where sGC governs smooth muscle tone and growth, vascular permeability, leukocyte flux, and platelet aggregation. As a consequence, aberrant NO-sGC signaling has been linked to diseases including hypertension, atherosclerosis, and stroke. Despite these key (patho)physiological roles, little is known about the expressional regulation of sGC. To address this deficit, we have characterized the promoter activity of human alpha(1) and beta(1) sGC genes in a cell type relevant to cardiovascular (patho)physiology, primary human aortic smooth muscle cells. Luciferase reporter constructs revealed that the 0.3- and 0.5-kb regions upstream of the transcription start sites were optimal for alpha(1) and beta(1) sGC promoter activity, respectively. Deletion of consensus sites for c-Myb, GAGA, NFAT, NF-kappaB(p50), and CCAAT-binding factor(s) (CCAAT-BF) revealed that these are the principal transcription factors regulating basal sGC expression. In addition, under pro-inflammatory conditions, the effects of the strongest alpha(1) and beta(1) sGC repressors were enhanced, and enzyme expression and activity were reduced; in particular, NF-kappaB(p50) is pivotal in regulating enzyme expression under such conditions. NO itself also elicited a cGMP-independent negative feedback effect on sGC promoter activity that is mediated, in part, via CCAAT-BF activity. In sum, these data provide a systematic characterization of the promoter activity of human sGC alpha(1) and beta(1) subunits and identify key transcription factors that govern subunit expression under basal and pro-inflammatory (i.e. atherogenic) conditions and in the presence of ligand NO.
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PMID:Characterization of the human alpha1 beta1 soluble guanylyl cyclase promoter: key role for NF-kappaB(p50) and CCAAT-binding factors in regulating expression of the nitric oxide receptor. 1847