Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P01185 (vasopressin)
 23,126 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Arginine vasopressin (AVP) increases the water permeability of renal collecting duct principal cells by inducing the fusion of vesicles containing the water channel aquaporin-2 (AQP2) with the plasma membrane (AQP2 shuttle). This event is initiated by activation of vasopressin V2 receptors, followed by an elevation of cAMP and the activation of protein kinase A (PKA). The tethering of PKA to subcellular compartments by protein kinase A anchoring proteins (AKAPs) is a prerequisite for the AQP2 shuttle. During the search for AKAP(s) involved in the shuttle, a new splice variant of AKAP18, AKAP18delta, was identified. AKAP18delta functions as an AKAP in vitro and in vivo. In the kidney, it is mainly expressed in principal cells of the inner medullary collecting duct, closely resembling the distribution of AQP2. It is present in both the soluble and particulate fractions derived from renal inner medullary tissue. Within the particulate fraction, AKAP18delta was identified on the same intracellular vesicles as AQP2 and PKA. AVP not only recruited AQP2, but also AKAP18delta to the plasma membrane. The elevation of cAMP caused the dissociation of AKAP18delta and PKA. The data suggest that AKAP18delta is involved in the AQP2 shuttle.
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PMID:Identification of a novel A-kinase anchoring protein 18 isoform and evidence for its role in the vasopressin-induced aquaporin-2 shuttle in renal principal cells. 1503 26

The cAMP/PKA (protein kinase A) signalling pathway is activated by a plethora of stimuli. To facilitate the specificity of a cellular response, signal transduction complexes are formed and segregated to discrete sites (compartmentalization). cAMP/PKA signalling compartments are maintained by AKAPs (A-kinase anchoring proteins) which bind PKA and other signalling proteins, and by PDEs (phosphodiesterases). The latter hydrolyse cAMP and thus limit its diffusion and terminate PKA activity. An example of a cAMP-dependent process requiring compartmentalization of cAMP/PKA signals is arginine-vasopressin-regulated water reabsorption in renal principal cells. A detailed understanding of the protein interactions within a signal transduction complex offers the possibility to design agents influencing PKA binding to a specific AKAP, the targeting of an AKAP or the interactions of AKAPs with other signalling molecules. The ability to specifically modulate selected branches of a signal transduction pathway would greatly advance basic research, and may lead to new drugs suitable for the treatment of diseases caused by dysregulation of anchored PKA signalling (e.g. renal and cardiovascular diseases).
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PMID:Compartmentalized cAMP signalling regulates vasopressin-mediated water reabsorption by controlling aquaporin-2. 1624 7

Adaptor or scaffolding proteins are at the basis of multiprotein complexes that spatially and temporally co-ordinate the propagation and integration of a broad range of cellular events. One class of scaffolding proteins are AKAPs (A-kinase-anchoring proteins). They sequester PKA (protein kinase A) and other signalling molecules including phosphodiesterases, other protein kinases and protein phosphatases to specific subcellular compartments. AKAP-dependent protein-protein interactions play a role in many physiologically relevant processes. For example, AKAP-PKA interactions are essential for the vasopressin-mediated water re-absorption in renal collecting duct principal cells or beta-adrenoceptor-induced increases in cardiac myocyte contractility. Here, we discuss recently developed peptide disruptors of AKAP-PKA interactions. Such peptides are valuable tools to study the relevance of PKA anchoring in cellular processes.
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PMID:Peptides for disruption of PKA anchoring. 1685 35