title: Phytochrome coordinates Arabidopsis shoot and root development.
abstract: The phytochrome family of photoreceptors are potent regulators of plant development, affecting a broad range of responses throughout the plant life cycle, including hypocotyl elongation, leaf expansion and apical dominance. The plant hormone auxin has previously been linked to these phytochrome-mediated responses; however, these studies have not identified the molecular mechanisms that underpin such extensive phytochrome and auxin cross-talk. In this paper, we show that phytochrome regulates the emergence of lateral roots, at least partly by manipulating auxin distribution within the seedling. Thus, shoot-localized phytochrome is able to act over long distances, through manipulation of auxin, to regulate root development. This work reveals an important role for phytochrome as a coordinator of shoot and root development, and provides insights into how phytochrome is able to exert such a powerful effect on growth and development. This new link between phytochrome and auxin may go some way to explain the extensive overlap in responses mediated by these two developmental regulators.
authors.affiliation: Institute of Molecular Plant Sciences, Edinburgh University, Kings Buildings, Mayfield Road, Edinburgh, EH9 3JR, UK.
authors.forename: Frances J
authors.initials: FJ
authors.lastname: Salisbury
authors.forename: Anthony
authors.initials: A
authors.lastname: Hall
authors.forename: Claire S
authors.initials: CS
authors.lastname: Grierson
authors.forename: Karen J
authors.initials: KJ
authors.lastname: Halliday
mesh_terms: D017360:Arabidopsis / Q000166:cytology / Q000254:growth & development* / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D002467:Cell Nucleus / Q000528:radiation effects; D018506:Gene Expression Regulation, Plant; D007210:Indoleacetic Acids / Q000378:metabolism; D008027:Light; D051942:Phytochrome A / Q000235:genetics / Q000378:metabolism*; D051939:Phytochrome B / Q000235:genetics / Q000378:metabolism*; D018517:Plant Roots / Q000166:cytology / Q000254:growth & development* / Q000378:metabolism; D018520:Plant Shoots / Q000254:growth & development* / Q000378:metabolism; D015398:Signal Transduction
chemical_list: D029681:Arabidopsis Proteins; D007210:Indoleacetic Acids; C497973:PHYA protein, Arabidopsis; C497952:PHYB protein, Arabidopsis; D051942:Phytochrome A; D051939:Phytochrome B