Intracellular Ca2＋ transients are an integral part of the signaling cascade during pathogen-associated molecular pattern （PAMP）-triggered immunity in plants. Yet, our knowledge about the spatial distribution of PAM...Intracellular Ca2＋ transients are an integral part of the signaling cascade during pathogen-associated molecular pattern （PAMP）-triggered immunity in plants. Yet, our knowledge about the spatial distribution of PAMP-induced Ca2＋ signals is limited. Investigation of cell- and tissue-specific properties of Ca2＋- dependent signaling processes requires versatile Ca2＋ reporters that are able to extract spatial information from cellular and subcellular structures, as well as from whole tissues over time periods from seconds to hours. Fluorescence-based reporters cover both a broad spatial and temporal range, which makes them ideally suited to study Ca2＋ signaling in living cells. In this study, we compared two fluorescence-based Ca2＋ sensors： the F6rster resonance energy transfer （FRET）-based reporter yellow cameleon NES-YC3.6 and the intensity-based sensor R-GECO1. We demonstrate that R-GECO1 exhibits a significantly increased signal change compared with ratiometric NES-YC3.6 in response to several stimuli. Due to its superior sensitivity, R-GECO1 is able to report fig22- and chitin-induced Ca2＋ signals on a cellular scale, which allowed identification of defined [Ca2＋]cyt oscillations in epidermal and guard cells in response to the fungal elicitor chitin. Moreover, we discovered that fig22- and chitin-induced Ca2＋ signals in the root initiate from the elongation zone.展开更多
文摘Intracellular Ca2＋ transients are an integral part of the signaling cascade during pathogen-associated molecular pattern （PAMP）-triggered immunity in plants. Yet, our knowledge about the spatial distribution of PAMP-induced Ca2＋ signals is limited. Investigation of cell- and tissue-specific properties of Ca2＋- dependent signaling processes requires versatile Ca2＋ reporters that are able to extract spatial information from cellular and subcellular structures, as well as from whole tissues over time periods from seconds to hours. Fluorescence-based reporters cover both a broad spatial and temporal range, which makes them ideally suited to study Ca2＋ signaling in living cells. In this study, we compared two fluorescence-based Ca2＋ sensors： the F6rster resonance energy transfer （FRET）-based reporter yellow cameleon NES-YC3.6 and the intensity-based sensor R-GECO1. We demonstrate that R-GECO1 exhibits a significantly increased signal change compared with ratiometric NES-YC3.6 in response to several stimuli. Due to its superior sensitivity, R-GECO1 is able to report fig22- and chitin-induced Ca2＋ signals on a cellular scale, which allowed identification of defined [Ca2＋]cyt oscillations in epidermal and guard cells in response to the fungal elicitor chitin. Moreover, we discovered that fig22- and chitin-induced Ca2＋ signals in the root initiate from the elongation zone.
