This Article Full Text Full Text (PDF) PPT slides of all figures Supplemental Data All Versions of this Article: 18/7/1722    most recent tpc.105.036269v1 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 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 Web of Science (13) Citing Articles via Google Scholar Google Scholar Articles by Wagner, S. Articles by Hellmann, H. Search for Related Content PubMed PubMed Citation Articles by Wagner, S. Articles by Hellmann, H. Agricola Articles by Wagner, S. Articles by Hellmann, H.

Analysis of the Arabidopsis rsr4-1/pdx1-3 Mutant Reveals the Critical Function of the PDX1 Protein Family in Metabolism, Development, and Vitamin B6 Biosynthesis^[W]

^a Angewandte Genetik, Freie Universität Berlin, 14195 Berlin, Germany
^b Institut für Pharmazeutische Biologie, Rheinische Friedrich-Wilhelms-Universität Bonn, 53115 Bonn, Germany
^c Max-Planck-Institut für Molekulare Pflanzenphysiologie, 14424 Potsdam, Germany
^d Department of Plant Biology, Stanford University, Stanford, California 94305

² To whom correspondence should be addressed. E-mail hellmann{at}zedat.fu-berlin.de; fax 49-30-83854345.

Vitamin B6 represents a highly important group of compounds ubiquitous in all living organisms. It has been demonstrated to alleviate oxidative stress and in its phosphorylated form participates as a cofactor in >100 biochemical reactions. By means of a genetic approach, we have identified a novel mutant, rsr4-1 (for reduced sugar response), with aberrant root and leaf growth that requires supplementation of vitamin B6 for normal development. Cloning of the mutated gene revealed that rsr4-1 carries a point mutation in a member of the PDX1/SOR1/SNZ (for Pyridoxine biosynthesis protein 1/Singlet oxygen resistant 1/Snooze) family that leads to reduced vitamin B6 content. Consequently, metabolism is broadly altered, mainly affecting amino acid, raffinose, and shikimate contents and trichloroacetic acid cycle constituents. Yeast two-hybrid and pull-down analyses showed that Arabidopsis thaliana PDX1 proteins can form oligomers. Interestingly, the mutant form of PDX1 has severely reduced capability to oligomerize, potentially suggesting that oligomerization is important for function. In summary, our results demonstrate the critical function of the PDX1 protein family for metabolism, whole-plant development, and vitamin B6 biosynthesis in higher plants.

This article has been cited by other articles:

				J. P. Craig, S. Bekal, M. Hudson, L. Domier, T. Niblack, and K. N. Lambert Analysis of a Horizontally Transferred Pathway Involved in Vitamin B6 Biosynthesis from the Soybean Cyst Nematode Heterodera glycines Mol. Biol. Evol., October 1, 2008; 25(10): 2085 - 2098. [Abstract] [Full Text] [PDF]

				A. Leblanc, H. Renault, J. Lecourt, P. Etienne, C. Deleu, and E. Le Deunff Elongation Changes of Exploratory and Root Hair Systems Induced by Aminocyclopropane Carboxylic Acid and Aminoethoxyvinylglycine Affect Nitrate Uptake and BnNrt2.1 and BnNrt1.1 Transporter Gene Expression in Oilseed Rape Plant Physiology, April 1, 2008; 146(4): 1928 - 1940. [Abstract] [Full Text] [PDF]

				S. Ruffel, S. Freixes, S. Balzergue, P. Tillard, C. Jeudy, M. L. Martin-Magniette, M. J. van der Merwe, K. Kakar, J. Gouzy, A. R. Fernie, et al. Systemic Signaling of the Plant Nitrogen Status Triggers Specific Transcriptome Responses Depending on the Nitrogen Source in Medicago truncatula Plant Physiology, April 1, 2008; 146(4): 2020 - 2035. [Abstract] [Full Text] [PDF]

				E. Gonzalez, D. Danehower, and M. E. Daub Vitamer Levels, Stress Response, Enzyme Activity, and Gene Regulation of Arabidopsis Lines Mutant in the Pyridoxine/Pyridoxamine 5'-Phosphate Oxidase (PDX3) and the Pyridoxal Kinase (SOS4) Genes Involved in the Vitamin B6 Salvage Pathway Plant Physiology, November 1, 2007; 145(3): 985 - 996. [Abstract] [Full Text] [PDF]

				T. Lemaitre, E. Urbanczyk-Wochniak, V. Flesch, E. Bismuth, A. R. Fernie, and M. Hodges NAD-Dependent Isocitrate Dehydrogenase Mutants of Arabidopsis Suggest the Enzyme Is Not Limiting for Nitrogen Assimilation Plant Physiology, July 1, 2007; 144(3): 1546 - 1558. [Abstract] [Full Text] [PDF]

				M. Tambasco-Studart, I. Tews, N. Amrhein, and T. B. Fitzpatrick Functional Analysis of PDX2 from Arabidopsis, a Glutaminase Involved in Vitamin B6 Biosynthesis Plant Physiology, June 1, 2007; 144(2): 915 - 925. [Abstract] [Full Text] [PDF]