Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0039483 (giant cell arteritis)
 3,204 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The membrane-bound atrial natriuretic peptide receptor (GCA) catalyzes the formation of cGMP from GTP in response to natriuretic peptide hormones. Previous structural studies have focused on the extra-cellular hormone binding domain of this receptor whereas its intra-cellular domain has not yet been amenable to such studies. We report here the baculovirus expression and purification of the GCA intra-cellular domain construct GCA(ID) comprising the complete intra-cellular region which includes the kinase-homology domain, coiled-coil region, and catalytic cyclase domain. The intra-cellular domain was enzymatically characterized in terms of guanylyl cyclase activity and the effects of ATP, manganese, and Triton X-100. Our results indicate that the activity of the intra-cellular domain of the ANP receptor is about 2 fold less active compared to a truncated cyclase domain construct lacking the kinase-like domain that was also expressed and purified. In addition, unlike the full length receptor, the intra-cellular domain could not be activated by Triton X-100/Mn(2+) or its activity stimulated by ATP. These data therefore indicate that the major part of the transition from the basal state to the fully, ANP/ATP-dependent, activated state as well its stimulation/enhancement by Triton X-100/Mn(2+) requires the full length receptor. These receptor insights could aid in the development of novel therapeutics as the GCA receptor is a key drug target for cardiovascular diseases.
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PMID:Expression, purification, and characterization of the intra-cellular domain of the ANP receptor. 1939 86

NPR1/GCA (natriuretic peptide receptor 1/guanylyl cyclase A) expression is controlled by several agents, including ANP (atrial natriuretic peptide). After ANP stimulation, NPR1/GCA down-regulates the transcriptional activity of its gene via a cGMP-dependent mechanism. Because we previously identified a cis-acting element responsible for this cGMP sensitivity, we proceed here to explore novel putative protein binding to cGMP-response element (cGMP-RE). Using the yeast one-hybrid technique with a human kidney cDNA library, we identified a strong positive clone able to bind cGMP-RE. The clone was derived from 1083-bp-long cDNA of a gene of yet unknown function localized on human chromosome 1 (1p33.36). We named this new protein GREBP (for cGMP-response element-binding protein). DNA binding assays showed 18-fold higher cGMP-RE binding capacity than the controls, whereas an electromobility shift assay indicated a specific binding for the cGMP-RE, and chromatin immunoprecipitation confirmed the binding of GREBP to the element under physiological conditions. By acting on cGMP-RE, GREBP inhibited the expression of a luciferase-coupled NPR1 promoter construct. In H295R cells, ANP heightened GREBP expression by 60% after just 3 h of treatment while inhibiting NPR1/GCA expression by 30%. Silencing GREBP with specific small interfering RNA increased the activity of the luciferase-coupled NPR1 promoter and GCA/NPR1 mRNA levels. GREBP is a nuclear protein mainly expressed in the heart. We report here the existence of a human-specific gene that acts as a transcriptional repressor of the NPR1/GCA gene.
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PMID:GREBP, a cGMP-response element-binding protein repressing the transcription of natriuretic peptide receptor 1 (NPR1/GCA). 2044 5