%0 Journal Article %1 koers2011barley %A Koers, S. %A Guzel-Deger, A. %A Marten, I. %A Roelfsema, M. R. G. %D 2011 %J Plant Journal %K S-type anion-channel barley chitosan guard-cell mildew %N 4 %P 670-680 %R 10.1111/j.1365-313X.2011.04719.x %T Barley mildew and its elicitor chitosan promote closed stomata by stimulating guard-cell S-type anion channels %U http://onlinelibrary.wiley.com/doi/10.1111/j.1365-313X.2011.04719.x/full %V 68 %X Stomatal closure is known to be associated with early defence responses of plant cells triggered by microbe-associated molecular patterns (MAMPs). However, the molecular mechanisms underlying these guard-cell responses have not yet been elucidated. We therefore studied pathogen-induced changes in ion channel activity in Hordeum vulgare guard cells. Barley mildew (Blumeria graminis) hyphae growing on leaves inhibited light-induced stomatal opening, starting at 9 h after inoculation, when appressoria had developed. Alternatively, stomatal closure was induced by nano-infusion of chitosan via open stomata into the sub-stomatal cavity. Experiments using intracellular double-barreled micro-electrodes revealed that mildew stimulated S-type (slow) anion channels in guard cells. These channels enable the efflux of anions from guard cells and also promote K+ extrusion by altering the plasma membrane potential. Stimulation of S-type anion channels was also provoked by nano-infusion of chitosan. These data suggest that MAMPs of mildew hyphae penetrating the cuticle provoke activation of S-type anion channels in guard cells. In response, guard cells extrude K+ salts, resulting in stomatal closure. Plasma membrane anion channels probably represent general targets of MAMP signaling in plants, as these elicitors depolarize the plasma membrane of various cell types.

@article{koers2011barley, abstract = {Stomatal closure is known to be associated with early defence responses of plant cells triggered by microbe-associated molecular patterns (MAMPs). However, the molecular mechanisms underlying these guard-cell responses have not yet been elucidated. We therefore studied pathogen-induced changes in ion channel activity in Hordeum vulgare guard cells. Barley mildew (Blumeria graminis) hyphae growing on leaves inhibited light-induced stomatal opening, starting at 9 h after inoculation, when appressoria had developed. Alternatively, stomatal closure was induced by nano-infusion of chitosan via open stomata into the sub-stomatal cavity. Experiments using intracellular double-barreled micro-electrodes revealed that mildew stimulated S-type (slow) anion channels in guard cells. These channels enable the efflux of anions from guard cells and also promote K+ extrusion by altering the plasma membrane potential. Stimulation of S-type anion channels was also provoked by nano-infusion of chitosan. These data suggest that MAMPs of mildew hyphae penetrating the cuticle provoke activation of S-type anion channels in guard cells. In response, guard cells extrude K+ salts, resulting in stomatal closure. Plasma membrane anion channels probably represent general targets of MAMP signaling in plants, as these elicitors depolarize the plasma membrane of various cell types.}, added-at = {2017-04-04T14:43:53.000+0200}, author = {Koers, S. and Guzel-Deger, A. and Marten, I. and Roelfsema, M. R. G.}, biburl = {https://www.bibsonomy.org/bibtex/22ba862431bb2a1580cc5772a91700fb3/robroelfsema}, doi = {10.1111/j.1365-313X.2011.04719.x}, interhash = {0b0975d63391bbad230a13e759997567}, intrahash = {2ba862431bb2a1580cc5772a91700fb3}, issn = {09607412}, journal = {Plant Journal}, keywords = {S-type anion-channel barley chitosan guard-cell mildew}, number = 4, pages = {670-680}, refid = {16}, timestamp = {2017-04-04T14:48:22.000+0200}, title = {Barley mildew and its elicitor chitosan promote closed stomata by stimulating guard-cell S-type anion channels}, url = {http://onlinelibrary.wiley.com/doi/10.1111/j.1365-313X.2011.04719.x/full}, volume = 68, year = 2011 }