AVPR2 siRNA – Vasopressin V2 Receptor Isoform 1 (Human)

This gene encodes the vasopressin receptor, type 2, also known as the V2 receptor, which belongs to the seven-transmembrane-domain G protein-coupled receptor (GPCR) superfamily, and couples to Gs thus stimulating adenylate cyclase. The subfamily that includes the V2 receptor, the V1a and V1b vasopressin receptors, the oxytocin receptor, and isotocin and mesotocin receptors in non-mammals, is well conserved, though several members signal via other G proteins. All bind similar cyclic nonapeptide hormones. The V2 receptor is expressed in the kidney tubule, predominantly in the distal convoluted tubule and collecting ducts, where its primary property is to respond to the pituitary hormone arginine vasopressin (AVP) by stimulating mechanisms that concentrate the urine and maintain water homeostasis in the organism. When the function of this gene is lost, the disease Nephrogenic Diabetes Insipidus (NDI) results. The V2 receptor is also expressed outside the kidney although its tissue localization is uncertain. When these 'extrarenal receptors' are stimulated by infusion of a V2 selective agonist (dDAVP), a variety of clotting factors are released into the bloodstream. The physiologic importance of this property is not known - its absence does not appear to be detrimental in NDI patients. The gene expression has also been described in fetal lung tissue and lung cancer associated with alternative splicing. [provided by RefSeq, Jul 2008]

AVPR2: Receptor for arginine vasopressin. The activity of this receptor is mediated by G proteins which activate adenylate cyclase. Involved in renal water reabsorption. Defects in AVPR2 are the cause of nephrogenic syndrome of inappropriate antidiuresis (NSIAD). This disorder is characterized by an inability to excrete a free water load, with inappropriately concentrated urine and resultant hyponatremia, hypoosmolarity, and natriuresis. Defects in AVPR2 are the cause of diabetes insipidus nephrogenic X-linked (XNDI); also known as diabetes insipidus nephrogenic type 1. XNDI is caused by the inability of the renal collecting ducts to absorb water in response to arginine vasopressin. It is characterized by excessive water drinking (polydypsia), excessive urine excretion (polyuria), persistent hypotonic urine, and hypokalemia. Belongs to the G-protein coupled receptor 1 family. Vasopressin/oxytocin receptor subfamily. 2 isoforms of the human protein are produced by alternative splicing.

Protein type: Receptor, GPCR; Transporter; GPCR, family 1; Transporter, aquaporin family; Membrane protein, multi-pass; Membrane protein, integral

Chromosomal Location of Human Ortholog: Xq28

Cellular Component: Golgi apparatus; integral to plasma membrane; endoplasmic reticulum; plasma membrane; integral to membrane; endosome

Molecular Function: protein binding; peptide binding; vasopressin receptor activity

Biological Process: I-kappaB kinase/NF-kappaB cascade; water transport; adenylate cyclase activation; positive regulation of systemic arterial blood pressure; excretion; cellular response to hormone stimulus; G-protein signaling, coupled to cAMP nucleotide second messenger; telencephalon development; regulation of systemic arterial blood pressure by vasopressin; hemostasis; positive regulation of protein ubiquitination; response to cytokine stimulus; positive regulation of cell proliferation; interferon-gamma production; positive regulation of vasoconstriction; renal water homeostasis; transmembrane transport

Disease: Nephrogenic Syndrome Of Inappropriate Antidiuresis; Diabetes Insipidus, Nephrogenic, X-linked