title: The Cdk5 kinase downregulates ATP-gated ionotropic P2X3 receptor function via serine phosphorylation.
abstract: Cdk5 is an endogenous kinase activated by the neuronal-specific protein p35 and implicated in multiple neuronal functions, including modulation of certain pain responses. We investigated whether Cdk5 could regulate ATP-gated P2X(3) receptors that are members of the family of membrane proteins expressed by sensory neurons to transduce nociception in baseline and chronic pain. To study the potential P2X(3) receptor modulation by Cdk5, we co-transfected rat P2X(3) receptors and Cdk5 into HEK cells and observed increased P2X(3) receptor serine phosphorylation together with downregulation of receptor currents only when these genes were transfected together with the gene of the Cdk5 activator p35. The changes in receptor responses were limited to depressed current amplitude as desensitization and recovery were not altered. Transfection of p35 with P2X(3) similarly downregulated receptor responses, suggesting that this phenomenon could be observed even with constitutive Cdk5. The present data indicate a novel target to express the action of Cdk5 on membrane proteins involved in pain perception.
authors: Neurobiology Sector and Italian Institute of Technology Unit, International School for Advanced Studies (SISSA), Via Beirut 2-4, 34151, Trieste, Italy.
authors: Asha
authors: A
authors: Nair
authors: Manuela
authors: M
authors: Simonetti
authors: Elsa
authors: E
authors: Fabbretti
authors: Andrea
authors: A
authors: Nistri
mesh_terms: D000818:Animals; D002460:Cell Line; D051360:Cyclin-Dependent Kinase 5 / Q000235:genetics / Q000378:metabolism*; D015536:Down-Regulation; D006801:Humans; D010146:Pain / Q000503:physiopathology*; D018408:Patch-Clamp Techniques; D010766:Phosphorylation; D051381:Rats; D018048:Receptors, Purinergic P2 / Q000235:genetics / Q000378:metabolism*; D058477:Receptors, Purinergic P2X3; D012694:Serine / Q000378:metabolism*
chemical_list: C546407:P2RX3 protein, human; C546410:P2rx3 protein, rat; D018048:Receptors, Purinergic P2; D058477:Receptors, Purinergic P2X3; D012694:Serine; D051360:Cyclin-Dependent Kinase 5