RRC ID 52862
Author Park J, Nguyen KT, Park E, Jeon JS, Choi G.
Title DELLA proteins and their interacting RING Finger proteins repress gibberellin responses by binding to the promoters of a subset of gibberellin-responsive genes in Arabidopsis.
Journal Plant Cell
Abstract DELLA proteins, consisting of GA INSENSITIVE, REPRESSOR OF GA1-3, RGA-LIKE1 (RGL1), RGL2, and RGL3, are central repressors of gibberellin (GA) responses, but their molecular functions are not fully understood. We isolated four DELLA-interacting RING domain proteins, previously designated as BOTRYTIS SUSCEPTIBLE1 INTERACTOR (BOI), BOI-RELATED GENE1 (BRG1), BRG2, and BRG3 (collectively referred to as BOIs). Single mutants of each BOI gene failed to significantly alter GA responses, but the boi quadruple mutant (boiQ) showed a higher seed germination frequency in the presence of paclobutrazol, precocious juvenile-to-adult phase transition, and early flowering, all of which are consistent with enhanced GA signaling. By contrast, BOI overexpression lines displayed phenotypes consistent with reduced GA signaling. Analysis of a gai-1 boiQ pentuple mutant further indicated that the GAI protein requires BOIs to inhibit a subset of GA responses. At the molecular level, BOIs did not significantly alter the stability of a DELLA protein. Instead, BOI and DELLA proteins are targeted to the promoters of a subset of GA-responsive genes and repress their expression. Taken together, our results indicate that the DELLA and BOI proteins inhibit GA responses by interacting with each other, binding to the same promoters of GA-responsive genes, and repressing these genes.
Volume 25(3)
Pages 927-43
Published 2013-3
DOI 10.1105/tpc.112.108951
PII tpc.112.108951
PMID 23482857
PMC PMC3634697
MeSH Arabidopsis / drug effects Arabidopsis / genetics Arabidopsis / growth & development Arabidopsis / metabolism* Arabidopsis Proteins / genetics Arabidopsis Proteins / metabolism* Flowers / genetics Flowers / growth & development Flowers / metabolism Gene Expression Regulation, Plant* Genes, Plant Germination Gibberellins / metabolism* Phenotype Plants, Genetically Modified / genetics Plants, Genetically Modified / growth & development Plants, Genetically Modified / metabolism Promoter Regions, Genetic* Protein Binding Protein Interaction Mapping Protein Stability RING Finger Domains Repressor Proteins / genetics Repressor Proteins / metabolism Seeds / drug effects Seeds / genetics Seeds / growth & development Seeds / metabolism Signal Transduction Transcription Factors / genetics Transcription Factors / metabolism* Triazoles / pharmacology Two-Hybrid System Techniques
IF 8.228
Resource
Arabidopsis / Cultured plant cells, genes psh12304