Hydrogen sulfide, a novel gasotransmitter involved in guard cell signalling

CARLOS GARCIA-MATA; LORENZO LAMATTINA

NEW PHYTOLOGIST

WILEY-BLACKWELL PUBLISHING, INC

Año: 2010 vol. 188 p. 977 - 984

0028-646X

• Hydrogen sulphide (H2S) has been proposed as the third gasotransmiter. In animal cells, H2S has been implicated in several physiological processes. H2S is endogenously synthesized both in animals and plants by enzymes with L-Cys desulfhydrase activity in the conversion of L-Cys to H2S, pyruvate and amonia. • The participation of H2S in both stomatal movement regulation and ABA-dependent induction of stomatal closure was studied in epidermal strips of three plant species (Vicia faba, Arabidopsis thaliana and Impatiens walleriana). The effect of H2S on stomatal movement was contrasted with leaf relative water content (RWC) measurements of whole plants subjected to water stress. • In this work we report that (i) exogenous H2S induces stomatal closure and this effect is impaired by the ABC transporter inhibitor Glibenclamide, (ii) inhibition of the enzyme responsible for endogenous H2S synthesis partially blocks ABA-dependent stomatal closure and (iii) H2S treatment increases RWC and protects plants against drought stress. • Our results indicate that H2S induces stomatal closure and participates in ABA-dependent signalling possibly through the regulation of ABC transporters in guard cells.