title: DR5 as a reporter system to study auxin response in Populus.
abstract: KEY MESSAGE                 :                                     Auxin responsive promoter DR5 reporter system is functional in Populus to monitor auxin response in tissues including leaves, roots, and stems.                                                                  We described the behavior of the DR5::GUS reporter system in stably transformed Populus plants. We found several similarities with Arabidopsis, including sensitivity to native and synthetic auxins, rapid induction after treatment in a variety of tissues, and maximal responses in root tissues. There were also several important differences from Arabidopsis, including slower time to maximum response and lower induction amplitude. Young leaves and stem sections below the apex showed much higher DR5 activity than did older leaves and stems undergoing secondary growth. DR5 activity was highest in cortex, suggesting high levels of auxin concentration and/or sensitivity in this tissue. Our study shows that the DR5 reporter system is a sensitive and facile system for monitoring auxin responses and distribution at cellular resolution in poplar.
authors.affiliation: Michigan Technological University, School of Forest Research and Environmental Science, 1400 Townsend Drive, Houghton, MI 49931, USA.
authors.forename: Yiru
authors.initials: Y
authors.lastname: Chen
authors.forename: Yordan S
authors.initials: YS
authors.lastname: Yordanov
authors.forename: Cathleen
authors.initials: C
authors.lastname: Ma
authors.forename: Steven
authors.initials: S
authors.lastname: Strauss
authors.forename: Victor B
authors.initials: VB
authors.lastname: Busov
mesh_terms: D018506:Gene Expression Regulation, Plant; D005966:Glucuronidase; D007210:Indoleacetic Acids / Q000378:metabolism / Q000494:pharmacology*; D010940:Plant Proteins / Q000235:genetics* / Q000378:metabolism; D018517:Plant Roots / Q000166:cytology / Q000235:genetics / Q000502:physiology; D018547:Plant Stems / Q000166:cytology / Q000235:genetics / Q000502:physiology; D030821:Plants, Genetically Modified; D032107:Populus / Q000166:cytology / Q000235:genetics / Q000502:physiology*; D012038:Regeneration; D012680:Sensitivity and Specificity; D013997:Time Factors
chemical_list: D007210:Indoleacetic Acids; D010940:Plant Proteins; D005966:Glucuronidase