High impact information on NPR3

• The mature form of ANP-C has a disulfide-linked homodimeric structure and contains 5 conserved cysteine residues per subunit, all in the extracellular domain [1].
• Alignment of the cDNA sequences with that of the ANP-C gene indicated that the two forms of ANP-C receptor arise from a single gene by alternative splicing using one donor and two closely located acceptor sites [2].
• A novel form of type C atrial natriuretic peptide receptor (ANP-C) was identified, characterized, and shown to be a product of alternative RNA splicing [2].
• Sequencing of several clones of ANP-C cDNA isolated from a bovine lung cDNA library revealed the presence of a new clone encoding a 536-amino acid ANP-C [2].
• The nucleotide sequence of this novel clone is very similar to that of the previously cloned ANP-C which consists of 537 amino acids [2].

Biological context of NPR3

• Characterization of the phosphorylation state of natriuretic peptide receptor-C [3].
• To define the ligand-binding site of natriuretic peptide receptor (NPR), amino acid substitutions were carried out by site-directed mutagenesis at selected residues of bovine NPR-C [4].

Anatomical context of NPR3

• Regulation of natriuretic peptide receptors by thyrotropin in FRTL-5 rat thyroid cells: evidence for nonguanylate cyclase atrial natriuretic factor-binding sites in cells lacking the natriuretic peptide receptor C [5].
• In this report, we have investigated the phosphorylation state of NPR-C receptors present at high level in rat aortic smooth muscle cells (RASM) [3].
• In situ hybridization demonstrated both ANPRA and ANPRC mRNA selectively in the glomerular epithelial cells and ANPRA mRNA in the collecting duct cells of the inner medulla [6].
• RT-PCR and Northern analysis demonstrated expression of the natriuretic peptide receptors NPR-C and NPR-B but not NPR-A in rabbit gastric muscle cells [7].
• In reconstitution studies, VIP, cANP-(4-23), and guanosine 5'-O-(3-thiotriphosphate) stimulated NOS activity in membranes of COS-1 cells cotransfected with NPR-C and eNOS [7].

Associations of NPR3 with chemical compounds

• This analog, which retains many of the spatial relationships of the native molecule, binds to both ANP-A and ANP-C receptor subtypes, and triggers the production of cyclic-GMP by ANP-A [8].
• ANP[13-27][1-8], a truncated analog in which much of this binding domain has been removed, surprisingly maintains a high affinity for ANP-C; however, this peptide has lost the ability to activate the ANP-A-linked guanylate cyclase [8].
• ANP-C binding of ANP[13-27][1- 12] is roughly equipotent to that of ANP itself, although the ring cleavage falls within the putative ANP-C binding domain [8].
• 32P labeled cells, NPR-C purification and phosphoamino acid analysis clearly demonstrate that NPR-C exists as a phosphoprotein in RASM cells and that phosphorylation occurs exclusively on serine residues [3].

Other interactions of NPR3

• Quantitative analysis of the ribonuclease protection assay showed that the numbers of type A receptor (ANPRA) mRNA were 6.9 x 10(7) in the glomeruli and 10.4 x 10(7) molecules/micrograms of total RNA in the inner medulla, and that of type C receptor (ANPRC) mRNA was 21.7 x 10(7) molecules/micrograms of total RNA in the glomeruli [6].

Analytical, diagnostic and therapeutic context of NPR3

• The type C receptor (ANP-C or NPR-C) for the natriuretic peptides was demonstrated, by site-directed mutagenesis, to have an immunoglobulin-like disulfide bonding pattern that is very similar to that of the cytokine receptor superfamily [1].
• ANPRC was also localized on the foot processes of glomerular epithelial cells by immunohistochemistry using a specific antibody against the receptor [6].

References