The regulation of salt transport and blood pressure by the WNK-SPAK/OSR1 signalling pathway.
It has recently been shown that the WNK [with-no-K(Lys)] kinases (WNK1, WNK2, WNK3 and WNK4) have vital roles in the control of salt homeostasis and blood pressure. This Commentary focuses on recent findings that have uncovered the backbone of a novel signal-transduction network that is controlled by WNK kinases. Under hyperosmotic or hypotonic low-Cl- conditions, WNK isoforms are activated, and subsequently phosphorylate and activate the related protein kinases SPAK and OSR1. SPAK and OSR1 phosphorylate and activate ion co-transporters that include NCC, NKCC1 and NKCC2, which are targets for the commonly used blood-pressure-lowering thiazide-diuretic and loop-diuretic drugs. The finding that mutations in WNK1, WNK4, NCC and NKCC2 cause inherited blood-pressure syndromes in humans highlights the importance of these enzymes. We argue that these new findings indicate that SPAK and OSR1 are promising drug targets for the treatment of hypertension, because inhibiting these enzymes would reduce NCC and NKCC2 activity and thereby suppress renal salt re-absorption. We also discuss unresolved and controversial questions in this field of research.
MRC Protein Phosphorylation Unit, Sir James Black Centre, College of Life Sciences, University of Dundee, Dow Street, Dundee DD1 5EH, UK. c.j.z.richardson@dundee.ac.uk
Ciaran
C
Richardson
Dario R
DR
Alessi
D000042:Absorption / Q000187:drug effects / Q000235:genetics; D000818:Animals; D001794:Blood Pressure / Q000235:genetics; D002712:Chlorides / Q000378:metabolism*; D030342:Genetic Diseases, Inborn / Q000188:drug therapy / Q000235:genetics / Q000378:metabolism; D006801:Humans; D006973:Hypertension / Q000188:drug therapy / Q000235:genetics / Q000378:metabolism; D047908:Intracellular Signaling Peptides and Proteins; D007473:Ion Channels / Q000235:genetics / Q000378:metabolism; D017136:Ion Transport / Q000187:drug effects / Q000235:genetics; D007527:Isoenzymes / Q000235:genetics / Q000378:metabolism; D007668:Kidney / Q000378:metabolism; D015778:Minor Histocompatibility Antigens; D009154:Mutation; D017346:Protein Serine-Threonine Kinases / Q000235:genetics / Q000378:metabolism*; D049993:Sodium Chloride Symporter Inhibitors / Q000627:therapeutic use; D049994:Sodium Potassium Chloride Symporter Inhibitors / Q000627:therapeutic use; D013577:Syndrome; D000076204:WNK Lysine-Deficient Protein Kinase 1
D002712:Chlorides; D047908:Intracellular Signaling Peptides and Proteins; D007473:Ion Channels; D007527:Isoenzymes; D015778:Minor Histocompatibility Antigens; D049993:Sodium Chloride Symporter Inhibitors; D049994:Sodium Potassium Chloride Symporter Inhibitors; C118135:OXSR1 protein, human; C523482:WNK2 protein, human; D017346:Protein Serine-Threonine Kinases; C486409:STK39 protein, human; D000076204:WNK Lysine-Deficient Protein Kinase 1; C498743:WNK1 protein, human; C488586:WNK3 protein, human; C433806:WNK4 protein, human