title: Phototropism: translating light into directional growth.
abstract: Phototropism allows plants to align their photosynthetic tissues with incoming light. The direction of incident light is sensed by the phototropin family of blue light photoreceptors (phot1 and phot2 in Arabidopsis), which are light-activated protein kinases. The kinase activity of phototropins and phosphorylation of residues in the activation loop of their kinase domains are essential for the phototropic response. These initial steps trigger the formation of the auxin gradient across the hypocotyl that leads to asymmetric growth. The molecular events between photoreceptor activation and the growth response are only starting to be elucidated. In this review, we discuss the major steps leading from light perception to directional growth concentrating on Arabidopsis. In addition, we highlight links that connect these different steps enabling the phototropic response.
authors.affiliation: Department of Medical Genetics, Faculty of Biology and Medicine, University of Lausanne, Rue du Bugnon 27, CH-1005 Lausanne, Switzerland.
authors.forename: Tim
authors.initials: T
authors.lastname: Hohm
authors.forename: Tobias
authors.initials: T
authors.lastname: Preuten
authors.forename: Christian
authors.initials: C
authors.lastname: Fankhauser
mesh_terms: D007210:Indoleacetic Acids / Q000378:metabolism; D008027:Light; D018524:Phototropism / Q000528:radiation effects*; D063245:Plant Development / Q000528:radiation effects*; D010944:Plants / Q000378:metabolism / Q000528:radiation effects*; D015398:Signal Transduction / Q000528:radiation effects
chemical_list: D007210:Indoleacetic Acids