567
Entry URI http://metadb.riken.jp/db/SciNetS_ria224i/cria224u4ria224u17369372i
Entry name Vellosillo Tamara et al. 2007 Mar. Plant Cell 19(3):831-46.
Title Oxylipins produced by the 9-lipoxygenase pathway in Arabidopsis regulate lateral root development and defense responses through a specific signaling cascade.
Authors Cascón Tomas|Castresana Carmen|Dolan Liam|Hamberg Mats|López Miguel Angel|Martínez Marta|Vellosillo Tamara|Vicente Jorge
Abstract Arabidopsis thaliana seedling growth with pure oxylipins resulted in root waving, loss of root apical dominance, and decreased root elongation. 9-Hydroxyoctadecatrienoic acid (9-HOT) was a potent inducer of root waving. Studies with noxy2 (for nonresponding to oxylipins2), a new 9-HOT-insensitive mutant, and coronatine insensitive1-1 (jasmonate-insensitive) revealed at least three signaling cascades mediating the oxylipin actions. Treatment with 9-HOT resulted in a reduction in lateral roots and an increase in stage V primordia. Roots showed strong 9-lipoxygenase (9-LOX) activity, and root primordia expressed 9-LOX genes. These results, along with findings that noxy2 and mutants with defective 9-LOX activity showed increased numbers of lateral roots, suggest that 9-HOT, or a closely related 9-LOX product, is an endogenous modulator of lateral root formation. Histochemical and molecular analyses revealed that 9-HOT activated events common to development and defense responses. A subset of 9-HOT-responding root genes was also induced in leaves after 9-HOT treatment or pathogen inoculation. The results that noxy2 displayed altered root development, enhanced susceptibility to Pseudomonas, and reduced the activation of 9-HOT-responding genes are consistent with mechanistic links among these processes. The nature of the changes detected suggests that oxylipins from the 9-LOX pathway function in cell wall modifications required for lateral root development and pathogen arrest.
Pubmed ID 17369372
Journal The Plant cell
Volume 19
Issue 3
Pages 831-46
Publication date 2007 Mar
Num of phenotype gene 2