Control of specific gene expression by gibberellin and brassinosteroid.
We identified a recessive, brassinolide-insensitive mutant caused by a deletion allele (bri1-201) of the brassinosteroid (BR) receptor BRI1. The bri1-201 mutant displayed altered expression levels of genes differentially regulated by gibberellin (GA). RNA-blot analysis revealed that BR and GA antagonistically regulate the accumulation of mRNAs of the GA-responsive GASA1 gene, as well as the GA-repressible GA5 gene. Expression studies with cycloheximide indicated that the antagonistic effects of GA and BR on GA5 require de novo protein synthesis. Reporter transgene analyses and RNA-blot analysis showed that BR and GA modulate GA5 expression, at least in part, at the transcriptional level, and that the signals are independent and subtractive.
Bouquin
T
T
Department of Plant Physiology, Molecular Biology Institute, Copenhagen University, Øster Farimagsgade 2A, 1353 Copenhagen K, Denmark.
Meier
C
C
Foster
R
R
Nielsen
M E
ME
Mundy
J
J
D017360:Arabidopsis / Q000235:genetics* / Q000502:physiology; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism; D060406:Brassinosteroids; D002777:Cholestanols / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D002874:Chromosome Mapping; D003513:Cycloheximide / Q000494:pharmacology; D017353:Gene Deletion; D018506:Gene Expression Regulation, Plant; D017930:Genes, Reporter; D005875:Gibberellins / Q000819:agonists / Q000494:pharmacology*; D016296:Mutagenesis; D010641:Phenotype; D010940:Plant Proteins / Q000235:genetics* / Q000378:metabolism; D011494:Protein Kinases / Q000235:genetics* / Q000378:metabolism; D012333:RNA, Messenger / Q000032:analysis; D018749:RNA, Plant / Q000032:analysis; D020239:Receptor Cross-Talk / Q000502:physiology; D015398:Signal Transduction; D013260:Steroids, Heterocyclic / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D014158:Transcription, Genetic; D019076:Transgenes
D029681:Arabidopsis Proteins; D060406:Brassinosteroids; D002777:Cholestanols; D005875:Gibberellins; D010940:Plant Proteins; D012333:RNA, Messenger; D018749:RNA, Plant; D013260:Steroids, Heterocyclic; C093242:GASA protein, Arabidopsis; D003513:Cycloheximide; D011494:Protein Kinases; C108270:BRI1 protein, Arabidopsis; C023623:brassinolide