OPEN ACCESS ARTICLE

This Article Free via Open Access: OA OA Full Text Full Text (PDF) Supplemental Data OA All Versions of this Article: 20/2/367    most recent tpc.107.056119v1 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 ISI Web of Science 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 ISI Web of Science (13) Citing Articles via Google Scholar Google Scholar Articles by Kusano, H. Articles by Aoyama, T. Search for Related Content PubMed PubMed Citation Articles by Kusano, H. Articles by Aoyama, T. Agricola Articles by Kusano, H. Articles by Aoyama, T.

The Arabidopsis Phosphatidylinositol Phosphate 5-Kinase PIP5K3 Is a Key Regulator of Root Hair Tip Growth^[W],[OA]

^a Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011, Japan
^b Section of Plant Physiology, Swammerdam Institute for Life Science, University of Amsterdam, 1098 SM Amsterdam, The Netherlands
^c Department of Biological Science and Technology, Tokyo University of Science, Noda, Chiba 278-8510, Japan

¹ Address correspondence to aoyama{at}scl.kyoto-u.ac.jp.

Phosphatidylinositol 4,5-bisphosphate [PtdIns(4,5)P₂] functions as a site-specific signal on membranes to promote cytoskeletal reorganization and membrane trafficking. Localization of PtdIns(4,5)P₂ to apices of growing root hairs and pollen tubes suggests that it plays an important role in tip growth. However, its regulation and mode of action remain unclear. We found that Arabidopsis thaliana PIP5K3 (for Phosphatidylinositol Phosphate 5-Kinase 3) encodes a phosphatidylinositol 4-phosphate 5-kinase, a key enzyme producing PtdIns(4,5)P₂, that is preferentially expressed in growing root hairs. T-DNA insertion mutations that substantially reduced the expression of PIP5K3 caused significantly shorter root hairs than in the wild type. By contrast, overexpression caused longer root hairs and multiple protruding sites on a single trichoblast. A yellow fluorescent protein (YFP) fusion of PIP5K3, driven by the PIP5K3 promoter, complemented the short-root-hair phenotype. PIP5K3-YFP localized to the plasma membrane and cytoplasmic space of elongating root hair apices, to growing root hair bulges, and, notably, to sites about to form root hair bulges. The signal was greatest in rapidly growing root hairs and quickly disappeared when elongation ceased. These results provide evidence that PIP5K3 is involved in localizing PtdIns(4,5)P₂ to the elongating root hair apex and is a key regulator of the machinery that initiates and promotes root hair tip growth.

This article has been cited by other articles:

				E. Darwish, C. Testerink, M. Khalil, O. El-Shihy, and T. Munnik Phospholipid Signaling Responses in Salt-Stressed Rice Leaves Plant Cell Physiol., May 1, 2009; 50(5): 986 - 997. [Abstract] [Full Text] [PDF]

				T. Munnik and C. Testerink Plant phospholipid signaling: "in a nutshell" J. Lipid Res., April 1, 2009; 50(Supplement): S260 - S265. [Abstract] [Full Text] [PDF]

				L. Saavedra, V. Balbi, S. K. Dove, Y. Hiwatashi, K. Mikami, and M. Sommarin Characterization of Phosphatidylinositol Phosphate Kinases from the Moss Physcomitrella patens: PpPIPK1 and PpPIPK2 Plant Cell Physiol., March 1, 2009; 50(3): 595 - 609. [Abstract] [Full Text] [PDF]

				B. O. R. Bargmann, A. M. Laxalt, B. t. Riet, B. van Schooten, E. Merquiol, C. Testerink, M. A. Haring, D. Bartels, and T. Munnik Multiple PLDs Required for High Salinity and Water Deficit Tolerance in Plants Plant Cell Physiol., January 1, 2009; 50(1): 78 - 89. [Abstract] [Full Text] [PDF]

				T. Ischebeck, I. Stenzel, and I. Heilmann Type B Phosphatidylinositol-4-Phosphate 5-Kinases Mediate Arabidopsis and Nicotiana tabacum Pollen Tube Growth by Regulating Apical Pectin Secretion PLANT CELL, December 1, 2008; 20(12): 3312 - 3330. [Abstract] [Full Text] [PDF]

				E. Sousa, B. Kost, and R. Malho Arabidopsis Phosphatidylinositol-4-Monophosphate 5-Kinase 4 Regulates Pollen Tube Growth and Polarity by Modulating Membrane Recycling PLANT CELL, November 1, 2008; 20(11): 3050 - 3064. [Abstract] [Full Text] [PDF]

				L. Li, N. Saga, and K. Mikami Phosphatidylinositol 3-kinase activity and asymmetrical accumulation of F-actin are necessary for establishment of cell polarity in the early development of monospores from the marine red alga Porphyra yezoensis J. Exp. Bot., October 1, 2008; 59(13): 3575 - 3586. [Abstract] [Full Text] [PDF]

				C.-M. Yoo, J. Wen, C. M. Motes, J. A. Sparks, and E. B. Blancaflor A Class I ADP-Ribosylation Factor GTPase-Activating Protein Is Critical for Maintaining Directional Root Hair Growth in Arabidopsis Plant Physiology, August 1, 2008; 147(4): 1659 - 1674. [Abstract] [Full Text] [PDF]