Oxidant sensor in the cGMP-binding pocket of PKGIα regulates nitroxyl-mediated kinase activity

TY - JOUR

T1 - Oxidant sensor in the cGMP-binding pocket of PKGIα regulates nitroxyl-mediated kinase activity

AU - Donzelli, Sonia

AU - Goetz, Mara

AU - Schmidt, Kjestine

AU - Wolters, Markus

AU - Stathopoulou, Konstantina

AU - Diering, Simon

AU - Prysyazhna, Oleksandra

AU - Polat, Volkan

AU - Scotcher, Jenna

AU - Dees, Christian

AU - Subramanian, Hariharan

AU - Butt, Elke

AU - Kamynina, Alisa

AU - Schobesberger, Sophie

AU - King, S Bruce

AU - Nikolaev, Viacheslav O

AU - de Wit, Cor

AU - Leichert, Lars I

AU - Feil, Robert

AU - Eaton, Philip

AU - Cuello, Friederike

PY - 2017/8/30

Y1 - 2017/8/30

N2 - Despite the mechanisms for endogenous nitroxyl (HNO) production and action being incompletely understood, pharmacological donors show broad therapeutic promise and are in clinical trials. Mass spectrometry and site-directed mutagenesis showed that chemically distinct HNO donors 1-nitrosocyclohexyl acetate or Angeli's salt induced disulfides within cGMP-dependent protein kinase I-alpha (PKGIα), an interdisulfide between Cys42 of the two identical subunits of the kinase and a previously unobserved intradisulfide between Cys117 and Cys195 in the high affinity cGMP-binding site. Kinase activity was monitored in cells transfected with wildtype (WT), Cys42Ser or Cys117/195Ser PKGIα that cannot form the inter- or intradisulfide, respectively. HNO enhanced WT kinase activity, an effect significantly attenuated in inter- or intradisulfide-deficient PKGIα. To investigate whether the intradisulfide modulates cGMP binding, real-time imaging was performed in vascular smooth muscle cells expressing a FRET-biosensor comprising the cGMP-binding sites of PKGIα. HNO induced FRET changes similar to those elicited by an increase of cGMP, suggesting that intradisulfide formation is associated with activation of PKGIα. Intradisulfide formation in PKGIα correlated with enhanced HNO-mediated vasorelaxation in mesenteric arteries in vitro and arteriolar dilation in vivo in mice. HNO induces intradisulfide formation in PKGIα, inducing the same effect as cGMP binding, namely kinase activation and thus vasorelaxation.

AB - Despite the mechanisms for endogenous nitroxyl (HNO) production and action being incompletely understood, pharmacological donors show broad therapeutic promise and are in clinical trials. Mass spectrometry and site-directed mutagenesis showed that chemically distinct HNO donors 1-nitrosocyclohexyl acetate or Angeli's salt induced disulfides within cGMP-dependent protein kinase I-alpha (PKGIα), an interdisulfide between Cys42 of the two identical subunits of the kinase and a previously unobserved intradisulfide between Cys117 and Cys195 in the high affinity cGMP-binding site. Kinase activity was monitored in cells transfected with wildtype (WT), Cys42Ser or Cys117/195Ser PKGIα that cannot form the inter- or intradisulfide, respectively. HNO enhanced WT kinase activity, an effect significantly attenuated in inter- or intradisulfide-deficient PKGIα. To investigate whether the intradisulfide modulates cGMP binding, real-time imaging was performed in vascular smooth muscle cells expressing a FRET-biosensor comprising the cGMP-binding sites of PKGIα. HNO induced FRET changes similar to those elicited by an increase of cGMP, suggesting that intradisulfide formation is associated with activation of PKGIα. Intradisulfide formation in PKGIα correlated with enhanced HNO-mediated vasorelaxation in mesenteric arteries in vitro and arteriolar dilation in vivo in mice. HNO induces intradisulfide formation in PKGIα, inducing the same effect as cGMP binding, namely kinase activation and thus vasorelaxation.

KW - Journal Article

U2 - 10.1038/s41598-017-09275-1

DO - 10.1038/s41598-017-09275-1

M3 - SCORING: Journal article

C2 - 28855531

VL - 7

SP - 9938

JO - SCI REP-UK

JF - SCI REP-UK

SN - 2045-2322

IS - 1

ER -