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

ABSTRACT: 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.

SUBMITTER: Alvarez-Venegas R

PROVIDER: S-EPMC1458695 | biostudies-literature | 2006 Apr

REPOSITORIES: biostudies-literature

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

Alvarez-Venegas Raul R Sadder Monther M Hlavacka Andrej A Baluska Frantisek F Xia Yuannan Y Lu Guoqing G Firsov Alexey A Sarath Gautam G Moriyama Hideaki H Dubrovsky Joseph G JG Avramova Zoya Z

Proceedings of the National Academy of Sciences of the United States of America 20060403 15

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 ...[more]

PMID: 16585509

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