Genome-wide analysis revealed the complex regulatory network of brassinosteroid effects in photomorphogenesis.
Light and brassinosteroids (BRs) have been proved to be crucial in regulating plant growth and development; however, the mechanism of how they synergistically function is still largely unknown. To explore the underlying mechanisms in photomorphogenesis, genome-wide analyses were carried out through examining the gene expressions of the dark-grown WT or BR biosynthesis-defective mutant det2 seedlings in the presence of light stimuli or exogenous Brassinolide (BL). Results showed that BR deficiency stimulates, while BL treatment suppresses, the expressions of light-responsive genes and photomorphogenesis, confirming the negative effects of BR in photomorphogenesis. This is consistent with the specific effects of BR on the expression of genes involved in cell wall modification, cellular metabolism and energy utilization during dark-light transition. Further analysis revealed that hormone biosynthesis and signaling-related genes, especially those of auxin, were altered under BL treatment or light stimuli, indicating that BR may modulate photomorphogenesis through synergetic regulation with other hormones. Additionally, suppressed ubiquitin-cycle pathway during light-dark transition hinted the presence of a complicated network among light, hormone, and protein degradation. The study provides the direct evidence of BR effects in photomorphogenesis and identified the genes involved in BR and light signaling pathway, which will help to elucidate the molecular mechanism of plant photomorphogenesis.
Song
L I
LI
National Key Laboratory of Plant Molecular Genetics, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 300 Fenglin Road, 200032 Shanghai, China.
Zhou
Xiao-Yi
XY
National Key Laboratory of Plant Molecular Genetics, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 300 Fenglin Road, 200032 Shanghai, China.
Li
L I
LI
National Key Laboratory of Plant Molecular Genetics, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 300 Fenglin Road, 200032 Shanghai, China.
Xue
Liang-Jiao
LJ
National Key Laboratory of Plant Molecular Genetics, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 300 Fenglin Road, 200032 Shanghai, China.
Yang
X I
XI
National Key Laboratory of Plant Molecular Genetics, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 300 Fenglin Road, 200032 Shanghai, China.
Xue
Hong-Wei
HW
National Key Laboratory of Plant Molecular Genetics, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 300 Fenglin Road, 200032 Shanghai, China. Electronic address: hwxue@sibs.ac.cn.
D017360:Arabidopsis / Q000187:drug effects* / Q000235:genetics / Q000254:growth & development / Q000378:metabolism* / Q000528:radiation effects; D029681:Arabidopsis Proteins / Q000235:genetics / Q000502:physiology; D060406:Brassinosteroids; D002777:Cholestanols / Q000378:metabolism* / Q000494:pharmacology*; D047369:Chromatin Immunoprecipitation; D016000:Cluster Analysis; D018506:Gene Expression Regulation, Plant / Q000187:drug effects / Q000528:radiation effects; D018745:Genome, Plant / Q000235:genetics*; D055106:Genome-Wide Association Study; D008027:Light; D009024:Morphogenesis / Q000187:drug effects / Q000528:radiation effects; D030821:Plants, Genetically Modified / Q000187:drug effects / Q000235:genetics / Q000254:growth & development / Q000528:radiation effects; D011401:Promoter Regions, Genetic; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015398:Signal Transduction / Q000187:drug effects / Q000528:radiation effects; D013260:Steroids, Heterocyclic / Q000378:metabolism* / Q000494:pharmacology*
D029681:Arabidopsis Proteins; D060406:Brassinosteroids; D002777:Cholestanols; C098907:DET2 protein, Arabidopsis; D013260:Steroids, Heterocyclic; C023623:brassinolide