title: Overexpression of a tobacco small G protein gene NtRop1 causes salt sensitivity and hydrogen peroxide production in transgenic plants.
abstract: The small GTPases of Rop/Rho family is central regulators of important cellular processes in plants. Tobacco small G protein gene NtRop1 has been isolated; however, its roles in stress responses were unknown. In the present study, the genomic sequence of NtRop1 was cloned, which has seven exons and six introns, similar to the Rop gene structure from Arabidopsis. The NtRop1 gene was constitutively expressed in the different organs whereas the other six Rop genes from tobacco had differential expression patterns. The expression of the NtRop1 gene was moderately induced by methyl viologen, NaCl, and ACC treatments, but slightly inhibited by ABA treatment, with no significant induction by NAA treatment. The transgenic Arabidopsis plants overexpressing the NtRop1 showed increased salt sensitivity as can be seen from the reduced root growth and elevated relative electrolyte leakage. The hydrogen peroxide production was also promoted in the NtRop1-trangenic plants in comparison with wild type plants. These results imply that the NtRop1 may confer salt sensitivity through activation of H2O2 production during plant response to salt stress.
authors.affiliation: National Key Lab of Plant Genomics, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China.
authors.forename: YangRong
authors.initials: Y
authors.lastname: Cao
authors.forename: ZhiGang
authors.initials: Z
authors.lastname: Li
authors.forename: Tao
authors.initials: T
authors.lastname: Chen
authors.forename: ZhiGang
authors.initials: Z
authors.lastname: Zhang
authors.forename: JinSong
authors.initials: J
authors.lastname: Zhang
authors.forename: ShouYi
authors.initials: S
authors.lastname: Chen
mesh_terms: D029681:Arabidopsis Proteins / Q000235:genetics; D001483:Base Sequence; D003001:Cloning, Molecular; D017931:DNA Primers; D019204:GTP-Binding Proteins / Q000235:genetics*; D015870:Gene Expression; D017343:Genes, Plant; D006861:Hydrogen Peroxide / Q000378:metabolism*; D010940:Plant Proteins / Q000235:genetics*; D030821:Plants, Genetically Modified / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012965:Sodium Chloride; D014026:Nicotiana / Q000235:genetics* / Q000378:metabolism
chemical_list: D029681:Arabidopsis Proteins; D017931:DNA Primers; D010940:Plant Proteins; D012965:Sodium Chloride; D006861:Hydrogen Peroxide; D019204:GTP-Binding Proteins; C501663:ROP1 protein, Arabidopsis