Arabidopsis homolog of trithorax, ATX1, binds phosphatidylinositol 5-phosphate, and the two regulate a common set of target genes

• Published in: Proceedings of the National Academy of Sciences - PNAS Vol. 103; no. 15; pp. 6049 - 6054
• Main Authors: Alvarez-Venegas, R, Sadder, M, Hlavacka, A, Baluska, F, Xia, Y, Lu, G, Firsov, A, Sarath, G, Moriyama, H, Dubrovsky, J.G
• Format: Journal Article
• Language: English
• Published: United States National Academy of Sciences 11.04.2006
• Subjects: Amino Acid Sequence; Arabidopsis; Arabidopsis - genetics; Arabidopsis - metabolism; Arabidopsis Proteins - genetics; Arabidopsis Proteins - metabolism; Arabidopsis thaliana; binding capacity; binding proteins; Biological Sciences; Botany; Cell nucleus; cytochemistry; Epidermal cells; Gene expression; Gene expression regulation; Gene Expression Regulation, Plant; Genes; histochemistry; Histone-Lysine N-Methyltransferase; Histones; Ligands; Lipids; Models, Molecular; Molecular Sequence Data; phosphatidylinositol 5-phosphate; Phosphatidylinositol Phosphates - metabolism; Phosphatidylinositols; Plants; Protein Conformation; Receptors; regulatory proteins; signal transduction; transcription (genetics); Transcription Factors - deficiency; Transcription Factors - genetics; Transcription Factors - metabolism
• ISSN: 0027-8424; 1091-6490
• DOI: 10.1073/pnas.0600944103

The Arabidopsis homolog of trithorax, ATX1, regulates numerous functions in Arabidopsis beyond the homeotic genes. Here, we identified genome-wide targets of ATX1 and showed that ATX1 is a receptor for a lipid messenger, phosphatidylinositol 5-phosphate, PI5P. PI5P negatively affects ATX1 activity, suggesting a regulatory pathway connecting lipid-signaling with nuclear functions. We propose a model to illustrate how plants may respond to stimuli (external or internal) that elevate cellular PI5P levels by altering expression of ATX1-controlled genes.