RRC ID 11882
Author Takanashi K, Sugiyama A, Yazaki K.
Title Involvement of auxin distribution in root nodule development of Lotus japonicus.
Journal Planta
Abstract The symbiosis between legume plants and rhizobia causes the development of new organs, nodules which function as an apparatus for nitrogen fixation. In this study, the roles of auxin in nodule development in Lotus japonicus have been demonstrated using molecular genetic tools and auxin inhibitors. The expression of an auxin-reporter GH3 fused to β-glucuronidase (GUS) was analyzed in L. japonicus roots, and showed a strong signal in the central cylinder of the root, whereas upon rhizobium infection, generation of GUS signal was observed at the dividing outer cortical cells during the first nodule cell divisions. When nodules were developed to maturity, strong GUS staining was detected in vascular tissues of nodules, suggesting distinct auxin involvement in the determinate nodule development. Numbers and the development of nodules were affected by auxin transport inhibitors (1-naphthylphthalamic acid, NPA and triindobenzoic acid, TIBA), and by a newly synthesized auxin antagonist, α-(phenyl ethyl-2-one)-indole-3-acetic acid (PEO-IAA). The common phenotypical alteration by these auxin inhibitors was the inhibition in forming lenticel which is normally developed on the nodule surface from the root outer cortex. The inhibition of lenticel formation was correlated with the inhibition of nodule vascular bundle development. These results indicate that auxin is required for the normal development of determinate nodules in a multidirectional manner.
Volume 234(1)
Pages 73-81
Published 2011-7-1
DOI 10.1007/s00425-011-1385-0
PMID 21369920
MeSH Gene Expression Regulation, Plant / drug effects Glucuronidase / genetics Glucuronidase / metabolism Indoleacetic Acids / metabolism Lotus / drug effects Lotus / growth & development* Lotus / metabolism* Lotus / microbiology Nitrogen Fixation / drug effects Phthalimides / pharmacology Plant Growth Regulators / pharmacology Plant Roots / metabolism Rhizobium / growth & development Root Nodules, Plant / drug effects Root Nodules, Plant / growth & development Root Nodules, Plant / metabolism* Symbiosis
IF 3.39
Times Cited 44
Lotus / Glycine L. japonicus G. max