8-Mercapto-Cyclic GMP Mediates Hydrogen Sulfide-Induced Stomatal Closure in Arabidopsis

Plant Cell Physiol. 2015 Aug;56(8):1481-9. doi: 10.1093/pcp/pcv069. Epub 2015 May 14.


Plants are exposed to hydrogen sulfide (H2S) both exogenously, as it exists as a pollutant gas in the environment, and endogenously, as it is synthesized in cells. H2S has recently been found to function as a gaseous signaling molecule, but its signaling cascade remains unknown. Here, we examined H2S-mediated guard cell signaling in Arabidopsis. The H2S donor GYY4137 (morpholin-4-ium-4-methoxyphenyl [morpholino] phosphinodithioate) induced stomatal closure, which peaked after 150 min at 1 µM or after 90 min at 10 and 100 µM. After reaching maximal closure, stomatal apertures gradually increased in size in response to further exposure to GYY4137. GYY4137 induced nitric oxide (NO) generation in guard cells, and GYY4137-induced stomatal closure was reduced by an NO scavenger and inhibitors of NO-producing enzymes. Mass spectrometry analyses showed that GYY4137 induces the synthesis of 8-nitro-cGMP and 8-mercapto-cGMP and that this synthesis is mediated by NO. In addition, 8-mercapto-cGMP triggered stomatal closure. Moreover, inhibitor and genetic studies showed that calcium, cADP ribose and slow anion channel 1 act downstream of 8-mercapto-cGMP. This study therefore demonstrates that 8-mercapto-cGMP mediates the H2S signaling cascade in guard cells.

Keywords: 8-Mercapto-cGMP; 8-Nitro-cGMP, stomata; Arabidopsis thaliana L; Hydrogen sulfide; Nitric oxide.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Arabidopsis / drug effects*
  • Arabidopsis / genetics
  • Arabidopsis / physiology
  • Calcium / metabolism
  • Cyclic GMP / analogs & derivatives*
  • Cyclic GMP / pharmacology*
  • Hydrogen Sulfide / metabolism*
  • Morpholines / pharmacology
  • Mutation
  • Nitric Oxide / metabolism*
  • Organothiophosphorus Compounds / pharmacology
  • Plant Leaves / drug effects
  • Plant Leaves / genetics
  • Plant Leaves / physiology
  • Plant Stomata / drug effects
  • Plant Stomata / genetics
  • Plant Stomata / physiology*
  • Seedlings
  • Signal Transduction


  • 8-nitroguanosine 3',5'-cyclic monophosphate
  • GYY 4137
  • Morpholines
  • Organothiophosphorus Compounds
  • Nitric Oxide
  • Cyclic GMP
  • Calcium
  • Hydrogen Sulfide