title: Salt and osmotic stress cause rapid increases in Arabidopsis thaliana cGMP levels.
abstract: A guanylyl cyclase has been recently identified in Arabidopsis but, despite the use of pharmacological inhibitors to infer roles of the second messenger 3',5'-cyclic guanosine monophosphate (cGMP), very few measurements of actual cGMP levels in plants are available. Here, we demonstrate that cGMP levels in Arabidopsis seedlings increase rapidly (< or =5 s) and to different degrees after salt and osmotic stress, and that the increases are prevented by treatment with LY, an inhibitor of soluble guanylyl cyclases. In addition, we provide evidence to suggest that salt stress activates two cGMP signalling pathways - an osmotic, calcium-independent pathway and an ionic, calcium-dependent pathway.
authors.affiliation: Department of Molecular and Cell Biology, University of Cape Town, Private Bag Rondebosch 7701, South Africa.
authors.forename: Lara
authors.initials: L
authors.lastname: Donaldson
authors.forename: Ndiko
authors.initials: N
authors.lastname: Ludidi
authors.forename: Marc R
authors.initials: MR
authors.lastname: Knight
authors.forename: Chris
authors.initials: C
authors.lastname: Gehring
authors.forename: Katherine
authors.initials: K
authors.lastname: Denby
mesh_terms: D017360:Arabidopsis / Q000187:drug effects / Q000378:metabolism*; D002118:Calcium / Q000378:metabolism*; D006152:Cyclic GMP / Q000378:metabolism*; D007700:Kinetics; D009994:Osmolar Concentration; D015290:Second Messenger Systems / Q000187:drug effects / Q000502:physiology; D012965:Sodium Chloride / Q000494:pharmacology*; D013012:Sorbitol / Q000494:pharmacology
chemical_list: D012965:Sodium Chloride; D013012:Sorbitol; D006152:Cyclic GMP; D002118:Calcium