title: Influence of variation potential on resistance of the photosynthetic machinery to heating in pea.
abstract: Electrical signals [action potentials (APs) and variation potentials (VPs)] induced by local stimuli are a mechanism that underlies rapid plant response to environmental factors. Such signals induce a number of functional responses, including changes in photosynthesis. Ultimately, these responses are considered to increase plant resistance to stress factors, but this question has been poorly investigated. We studied the influence of VP on photosynthesis and resistance of the photosynthetic machinery to heating in leaves of pea (Pisum sativum). Localized burning induced a VP that decreased photosynthesis parameters [CO(2) assimilation rate and quantum yields of photosystem I (PSI) and photosystem II (PSII)]. The photosynthetic response was initiated by a decrease in photosynthesis dark-stage activity, which in turn increased resistance of PSI to heating. Three results supported this hypothesized mechanism: (1) the magnitude of VP-induced decrease in CO(2) assimilation and enhanced PSI resistance to heating were highly correlated; (2) the VP influence on PSI resistance to heating was suppressed under a low external CO(2) concentration and (3) decreasing external CO(2) concentration imitated the VP-induced photosynthetic response and increased PSI resistance to heating.
authors.affiliation: Department of Biophysics, N.I. Lobachevsky State University of Nizhny Novgorod, Nizhny Novgorod, 603950, Russia.
authors.forename: Vladimir
authors.initials: V
authors.lastname: Sukhov
authors.forename: Lyubov
authors.initials: L
authors.lastname: Surova
authors.forename: Oksana
authors.initials: O
authors.lastname: Sherstneva
authors.forename: Vladimir
authors.initials: V
authors.lastname: Vodeneev
mesh_terms: D002245:Carbon Dioxide / Q000378:metabolism; D002734:Chlorophyll / Q000378:metabolism; D002736:Chloroplasts / Q000378:metabolism; D004579:Electron Transport; D006361:Heating; D008027:Light; D018532:Pisum sativum / Q000378:metabolism*; D010788:Photosynthesis / Q000502:physiology*; D045331:Photosystem I Protein Complex / Q000378:metabolism; D045332:Photosystem II Protein Complex / Q000378:metabolism; D018515:Plant Leaves / Q000378:metabolism
chemical_list: D045331:Photosystem I Protein Complex; D045332:Photosystem II Protein Complex; D002734:Chlorophyll; D002245:Carbon Dioxide