Regulation of Auxin Homeostasis and Gradients in Arabidopsis Roots through the Formation of the Indole-3-Acetic Acid Catabolite 2-Oxindole-3-Acetic Acid
2013 (English)In: The Plant Cell, ISSN 1040-4651, E-ISSN 1532-298X, Vol. 25, no 10, 3858-3870 p.Article in journal (Refereed) Published
The native auxin, indole-3-acetic acid (IAA), is a major regulator of plant growth and development. Its nonuniform distribution between cells and tissues underlies the spatiotemporal coordination of many developmental events and responses to environmental stimuli. The regulation of auxin gradients and the formation of auxin maxima/minima most likely involve the regulation of both metabolic and transport processes. In this article, we have demonstrated that 2-oxindole-3-acetic acid (oxIAA) is a major primary IAA catabolite formed in Arabidopsis thaliana root tissues. OxIAA had little biological activity and was formed rapidly and irreversibly in response to increases in auxin levels. We further showed that there is cell type-specific regulation of oxIAA levels in the Arabidopsis root apex. We propose that oxIAA is an important element in the regulation of output from auxin gradients and, therefore, in the regulation of auxin homeostasis and response mechanisms.
Place, publisher, year, edition, pages
2013. Vol. 25, no 10, 3858-3870 p.
Botany Biochemistry and Molecular Biology Cell Biology
IdentifiersURN: urn:nbn:se:umu:diva-85109DOI: 10.1105/tpc.113.114421ISI: 000327723100019OAI: oai:DiVA.org:umu-85109DiVA: diva2:691600
FunderSwedish Research Council