This Article Full Text Full Text (PDF) PPT slides of all figures Supplemental Data All Versions of this Article: 21/7/1992    most recent tpc.109.065821v1 Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via CrossRef Citing Articles via Web of Science (2) Citing Articles via Google Scholar Google Scholar Articles by Strader, L. C. Articles by Bartel, B. Search for Related Content PubMed PubMed Citation Articles by Strader, L. C. Articles by Bartel, B. Agricola Articles by Strader, L. C. Articles by Bartel, B.

The Arabidopsis PLEIOTROPIC DRUG RESISTANCE8/ABCG36 ATP Binding Cassette Transporter Modulates Sensitivity to the Auxin Precursor Indole-3-Butyric Acid^[C],[W]

Department of Biochemistry and Cell Biology, Rice University, Houston, Texas 77005

¹ Address correspondence to bartel{at}rice.edu.

Plants have developed numerous mechanisms to store hormones in inactive but readily available states, enabling rapid responses to environmental changes. The phytohormone auxin has a number of storage precursors, including indole-3-butyric acid (IBA), which is apparently shortened to active indole-3-acetic acid (IAA) in peroxisomes by a process similar to fatty acid β-oxidation. Whereas metabolism of auxin precursors is beginning to be understood, the biological significance of the various precursors is virtually unknown. We identified an Arabidopsis thaliana mutant that specifically restores IBA, but not IAA, responsiveness to auxin signaling mutants. This mutant is defective in PLEIOTROPIC DRUG RESISTANCE8 (PDR8)/PENETRATION3/ABCG36, a plasma membrane–localized ATP binding cassette transporter that has established roles in pathogen responses and cadmium transport. We found that pdr8 mutants display defects in efflux of the auxin precursor IBA and developmental defects in root hair and cotyledon expansion that reveal previously unknown roles for IBA-derived IAA in plant growth and development. Our results are consistent with the possibility that limiting accumulation of the IAA precursor IBA via PDR8-promoted efflux contributes to auxin homeostasis.

This article has been cited by other articles:

				K. Ruzicka, L. C. Strader, A. Bailly, H. Yang, J. Blakeslee, L. Langowski, E. Nejedla, H. Fujita, H. Itoh, K. Syono, et al. Arabidopsis PIS1 encodes the ABCG37 transporter of auxinic compounds including the auxin precursor indole-3-butyric acid PNAS, June 8, 2010; 107(23): 10749 - 10753. [Abstract] [Full Text] [PDF]

				P. Overvoorde, H. Fukaki, and T. Beeckman Auxin Control of Root Development Cold Spring Harb Perspect Biol, June 1, 2010; 2(6): a001537 - a001537. [Abstract] [Full Text] [PDF]

				T. J. W. Yang, W. D. Lin, and W. Schmidt Transcriptional Profiling of the Arabidopsis Iron Deficiency Response Reveals Conserved Transition Metal Homeostasis Networks Plant Physiology, April 1, 2010; 152(4): 2130 - 2141. [Abstract] [Full Text] [PDF]

				L. C. Strader, E. R. Beisner, and B. Bartel Silver Ions Increase Auxin Efflux Independently of Effects on Ethylene Response PLANT CELL, November 1, 2009; 21(11): 3585 - 3590. [Abstract] [Full Text] [PDF]