okadaic-acid and brassinolide

RAV1 is a novel DNA-binding protein with two distinct DNA-binding domains unique in higher plants, but its role in plant growth and development remains unknown. Using cDNA array, we found that transcription of RAV1 is down-regulated by epibrassinolide (epiBL) in Arabidopsis suspension cells. RNA gel blot analysis revealed that epiBL-regulated RAV1 transcription involves neither protein phosphorylation/dephosphorylation nor newly synthesized protein, and does not require the functional BRI1, suggesting that this regulation might be through a new BR signaling pathway. Overexpressing RAV1 in Arabidopsis results in a retardation of lateral root and rosette leaf development, and the underexpression causes an earlier flowering phenotype, implying that RAV1 may function as a negative regulatory component of growth and development.

Topics: 2,4-Dichlorophenoxyacetic Acid; Arabidopsis; Arabidopsis Proteins; Blotting, Northern; Blotting, Southern; Blotting, Western; Brassinosteroids; Cholestanols; Cycloheximide; DNA-Binding Proteins; DNA, Antisense; Down-Regulation; Flowers; Gene Dosage; Gene Expression Regulation, Developmental; Gene Expression Regulation, Plant; Models, Biological; Mutation; Okadaic Acid; Oligonucleotide Array Sequence Analysis; Plant Growth Regulators; Plant Leaves; Plant Roots; Plants, Genetically Modified; Protein Kinases; Rhizobium; Signal Transduction; Staurosporine; Steroids, Heterocyclic; Transformation, Genetic; Zeatin