A zinc finger-containing glycine-rich RNA-binding protein, atRZ-1a, has a negative impact on seed germination and seedling growth of Arabidopsis thaliana under salt or drought stress conditions.
Despite the fact that glycine-rich RNA-binding proteins (GRPs) have been implicated in the responses of plants to changing environmental conditions, the reports demonstrating their biological roles are severely limited. Here, we examined the functional roles of a zinc finger-containing GRP, designated atRZ-1a, in Arabidopsis thaliana under drought or salt stress conditions. Transgenic Arabidopsis plants overexpressing atRZ-1a displayed retarded germination and seedling growth compared with the wild-type plants under salt or dehydration stress conditions. In contrast, the loss-of-function mutants of atRZ-1a germinated earlier and grew faster than the wild-type plants under the same stress conditions. Germination of the transgenic plants and mutant lines was influenced by the addition of ABA or glucose, implying that atRZ-1a affects germination in an ABA-dependent way. H(2)O(2) was accumulated at higher levels in the transgenic plants compared with the wild-type plants under stress conditions. The expression of several germination-responsive genes was modulated by atRZ-1a, and proteome analysis revealed that the expression of different classes of genes, including those involved in reactive oxygen species homeostasis and functions, was affected by atRZ-1a under dehydration or salt stress conditions. Taken together, these results suggest that atRZ-1a has a negative impact on seed germination and seedling growth of Arabidopsis under salt or dehydration stress conditions, and imply that atRZ-1a exerts its function by modulating the expression of several genes under stress conditions.
Kim
Yeon-Ok
YO
Department of Plant Biotechnology, Agricultural Plant Stress Research Center and Biotechnology Research Institute, College of Agriculture and Life Sciences, Chonnam National University, Gwangju, 500-757, Korea.
Pan
SangO
S
Jung
Che-Hun
CH
Kang
Hunseung
H
D000040:Abscisic Acid / Q000494:pharmacology; D017360:Arabidopsis / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism* / Q000502:physiology; D004190:Disasters; D015180:Electrophoresis, Gel, Two-Dimensional; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D018525:Germination / Q000235:genetics; D005947:Glucose / Q000494:pharmacology; D005998:Glycine / Q000378:metabolism; D009154:Mutation; D010937:Plant Growth Regulators / Q000494:pharmacology; D040901:Proteomics / Q000379:methods; D016601:RNA-Binding Proteins / Q000235:genetics / Q000378:metabolism* / Q000502:physiology; D020133:Reverse Transcriptase Polymerase Chain Reaction; D036226:Seedlings / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D012965:Sodium Chloride / Q000494:pharmacology
D029681:Arabidopsis Proteins; D010937:Plant Growth Regulators; D016601:RNA-Binding Proteins; D012965:Sodium Chloride; D000040:Abscisic Acid; D005947:Glucose; D005998:Glycine