title: Aequorin-based luminescence imaging reveals differential calcium signalling responses to salt and reactive oxygen species in rice roots.
abstract: It is well established that both salt and reactive oxygen species (ROS) stresses are able to increase the concentration of cytosolic free Ca(2+) ([Ca(2+)]i), which is caused by the flux of calcium (Ca(2+)). However, the differences between these two processes are largely unknown. Here, we introduced recombinant aequorin into rice (Oryza sativa) and examined the change in [Ca(2+)]i in response to salt and ROS stresses. The transgenic rice harbouring aequorin showed strong luminescence in roots when treated with exogenous Ca(2+). Considering the histological differences in roots between rice and Arabidopsis, we reappraised the discharging solution, and suggested that the percentage of ethanol should be 25%. Different concentrations of NaCl induced immediate [Ca(2+)]i spikes with the same durations and phases. In contrast, H₂O₂ induced delayed [Ca(2+)]i spikes with different peaks according to the concentrations of H₂O₂. According to the Ca(2+) inhibitor research, we also showed that the sources of Ca(2+) induced by NaCl and H₂O₂ are different. Furthermore, we evaluated the contribution of [Ca(2+)]i responses in the NaCl- and H₂O₂-induced gene expressions respectively, and present a Ca(2+)- and H₂O₂-mediated molecular signalling model for the initial response to NaCl in rice.
authors.affiliation: College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou 310036, China.
authors.forename: Yanyan
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Plant Physiology and Biochemistry, College of Life Science, Zhejiang University, Hangzhou 310058, China.
authors.forename: Yifeng
authors.initials: Y
authors.lastname: Wang
authors.affiliation: School of Life Sciences, Gibbet Hill Campus, University of Warwick, Coventry CV4 7AL, United Kingdom.
authors.forename: Jemma L
authors.initials: JL
authors.lastname: Taylor
authors.affiliation: College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou 310036, China.
authors.forename: Zhonghao
authors.initials: Z
authors.lastname: Jiang
authors.affiliation: College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou 310036, China.
authors.forename: Shu
authors.initials: S
authors.lastname: Zhang
authors.affiliation: College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou 310036, China.
authors.forename: Fengling
authors.initials: F
authors.lastname: Mei
authors.affiliation: State Key Laboratory of Plant Physiology and Biochemistry, College of Life Science, Zhejiang University, Hangzhou 310058, China.
authors.forename: Yunrong
authors.initials: Y
authors.lastname: Wu
authors.affiliation: State Key Laboratory of Plant Physiology and Biochemistry, College of Life Science, Zhejiang University, Hangzhou 310058, China.
authors.forename: Ping
authors.initials: P
authors.lastname: Wu
authors.affiliation: College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou 310036, China nijun@hznu.edu.cn.
authors.forename: Jun
authors.initials: J
authors.lastname: Ni
mesh_terms: D000331:Aequorin / Q000032:analysis / Q000378:metabolism; D001059:Apoproteins / Q000032:analysis / Q000378:metabolism; D020013:Calcium Signaling; D018506:Gene Expression Regulation, Plant; D012275:Oryza / Q000235:genetics / Q000378:metabolism*; D010940:Plant Proteins / Q000032:analysis / Q000378:metabolism; D018517:Plant Roots / Q000235:genetics / Q000378:metabolism; D030821:Plants, Genetically Modified / Q000378:metabolism; D017382:Reactive Oxygen Species / Q000378:metabolism*; D011994:Recombinant Proteins / Q000032:analysis / Q000378:metabolism; D012965:Sodium Chloride / Q000378:metabolism*
chemical_list: D001059:Apoproteins; D010940:Plant Proteins; D017382:Reactive Oxygen Species; D011994:Recombinant Proteins; C060014:apoaequorin; D012965:Sodium Chloride; D000331:Aequorin
keywords: Aequorin; Oryza sativa; calcium; reactive oxygen species; rice; root; salt.