title: Multiple Interactions between Glucose and Brassinosteroid Signal Transduction Pathways in Arabidopsis Are Uncovered by Whole-Genome Transcriptional Profiling.
abstract: Brassinosteroid (BR) and glucose (Glc) regulate many common responses in plants. Here, we demonstrate that under etiolated growth conditions, extensive interdependence/overlap occurs between BR- and Glc-regulated gene expression as well as physiological responses. Glc could regulate the transcript level of 72% of BR-regulated genes at the whole-genome level, of which 58% of genes were affected synergistically and 42% of genes were regulated antagonistically. Presence of Glc along with BR in medium could affect BR induction/repression of 85% of BR-regulated genes. Glc could also regulate several genes involved in BR metabolism and signaling. Both BR and Glc coregulate a large number of genes involved in abiotic/biotic stress responses and growth and development. Physiologically, Glc and BR interact to regulate hypocotyl elongation growth of etiolated Arabidopsis (Arabidopsis thaliana) seedlings in a dose-dependent manner. Glc may interact with BR via a hexokinase1 (HXK1)-mediated pathway to regulate etiolated hypocotyl elongation. Brassinosteroid insensitive1 (BRI1) is epistatic to HXK1, as the Glc insensitive2bri1-6 double mutant displayed severe defects in hypocotyl elongation growth similar to its bri1-6 parent. Analysis of Glc and BR sensitivity in mutants defective in auxin response/signaling further suggested that Glc and BR signals may converge at S-phase kinase-associated protein1-Cullin-F-box-transport inhibitor response1/auxin-related f-box-auxin/indole-3-acetic acid-mediated auxin-signaling machinery to regulate etiolated hypocotyl elongation growth in Arabidopsis.
authors.affiliation: National Institute of Plant Genome Research, New Delhi 110067, India.
authors.forename: Aditi
authors.identifier: http://orcid.org/0000-0002-3299-1625
authors.initials: A
authors.lastname: Gupta
authors.affiliation: National Institute of Plant Genome Research, New Delhi 110067, India.
authors.forename: Manjul
authors.identifier: http://orcid.org/0000-0001-9547-269X
authors.initials: M
authors.lastname: Singh
authors.affiliation: National Institute of Plant Genome Research, New Delhi 110067, India ashverya_laxmi@nipgr.ac.in.
authors.forename: Ashverya
authors.identifier: http://orcid.org/0000-0002-3430-4200
authors.initials: A
authors.lastname: Laxmi
mesh_terms: D017360:Arabidopsis / Q000187:drug effects / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism; D060406:Brassinosteroids / Q000378:metabolism* / Q000494:pharmacology; D003624:Darkness; D004843:Epistasis, Genetic / Q000187:drug effects; D064527:Etiolation / Q000187:drug effects; D020869:Gene Expression Profiling; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D017343:Genes, Plant; D018745:Genome, Plant; D005947:Glucose / Q000378:metabolism* / Q000494:pharmacology; D018546:Hypocotyl / Q000187:drug effects / Q000235:genetics / Q000254:growth & development; D007210:Indoleacetic Acids / Q000378:metabolism; D009024:Morphogenesis / Q000187:drug effects / Q000235:genetics; D020411:Oligonucleotide Array Sequence Analysis; D060888:Real-Time Polymerase Chain Reaction; D015203:Reproducibility of Results; D036226:Seedlings / Q000235:genetics / Q000254:growth & development; D015398:Signal Transduction / Q000187:drug effects / Q000235:genetics; D013312:Stress, Physiological / Q000187:drug effects / Q000235:genetics; D014158:Transcription, Genetic / Q000187:drug effects
chemical_list: D029681:Arabidopsis Proteins; D060406:Brassinosteroids; D007210:Indoleacetic Acids; D005947:Glucose