Nitric oxide inhibits the pannexin 1 channel through a cGMP-PKG dependent pathway.
Nitric oxide (NO), a major gaseous signaling molecule, modulates several ion channels and receptors. Here we show that NO attenuates pannexin 1 (Panx1) mediated currents in HEK-293 cells. NO exerts its effect by activating a cGMP-protein kinase G (PKG) dependent pathway. NO donors, sodium nitroprusside (SNP), S-nitroso-N-acetylpenicillamine (SNAP) and S-nitrosoglutathione (GSNO), reduced Panx1 currents by 25-41%. 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (ODQ), an inhibitor of soluble guanylyl cyclase (sGC), blocked the inhibition completely, whereas sGC activator YC-1 mimicked the effect of NO, suggesting the involvement of a cGMP dependent pathway. Supporting this, NO had no effect in the presence of the PKG inhibitor, KT5823. Further, immuno-precipitated Panx1 was recognized by an anti-phosphoserine antibody in Western blot. Phosphorylation was enhanced significantly when cells were treated with SNP. The target for phosphorylation is possibly Ser 206 of Panx1, as its mutation to Ala completely abolished the NO mediated inhibition.
Department of Biotechnology, Bhupat & Jyoti Mehta School of BioSciences, Indian Institute of Technology Madras, Sardar Patel Road, Chennai, Tamil Nadu 600036, India.
V
V
Poornima
Department of Biotechnology, Bhupat & Jyoti Mehta School of BioSciences, Indian Institute of Technology Madras, Sardar Patel Road, Chennai, Tamil Nadu 600036, India.
Sirisha
S
Vallabhaneni
Department of Biotechnology, Bhupat & Jyoti Mehta School of BioSciences, Indian Institute of Technology Madras, Sardar Patel Road, Chennai, Tamil Nadu 600036, India.
Mohona
M
Mukhopadhyay
Department of Biotechnology, Bhupat & Jyoti Mehta School of BioSciences, Indian Institute of Technology Madras, Sardar Patel Road, Chennai, Tamil Nadu 600036, India. Electronic address: amal@iitm.ac.in.
Amal Kanti
AK
Bera
D017630:Connexins / Q000037:antagonists & inhibitors* / Q000378:metabolism; D017869:Cyclic GMP-Dependent Protein Kinases / Q000378:metabolism*; D057809:HEK293 Cells; D006801:Humans; D009419:Nerve Tissue Proteins / Q000037:antagonists & inhibitors* / Q000378:metabolism; D009569:Nitric Oxide / Q000378:metabolism / Q000494:pharmacology*
D017630:Connexins; D009419:Nerve Tissue Proteins; C492764:PANX1 protein, human; D009569:Nitric Oxide; D017869:Cyclic GMP-Dependent Protein Kinases
Connexin; Ion channel; Nitric oxide; Pannexin; Phosphorylation; Protein kinase G; S-nitrosylation