Involvement of the Chromatin Modifier ATX1 and of the Arabidopsis Myotubularin Homolog (MYO1) in the Response to Drought

Plants respond to environmental stresses by altering transcription of genes involved in the response. The chromatin modifier ATX1 influences gene expression and factors that modulate ATX1 activity would affect indirectly the expression of ATX1-regulated genes. Here, we demonstrate that dehydration is such a factor indicating that ATX1 is involved in the plants response to drought. In addition, we show that a hitherto unknown Arabidopsis gene, At3g10550, encodes MYO1, a phosphoinositide 3-phosphatase related to the animal myotubularins. By a functional genomics approach, we show that ATX1 and MYO1 participate in overlapping drought-response pathways. The shared set of genes, representing the ultimate targets of an ATX1-MYO1 signaling mechanism responding to drought, provided insights into the relationship of the epigenetic factor and the lipid phosphatase from the other end of the response pathway.

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Ding Y, Lapko H, Ndamukong I, Xia Y, Al-Abdallat A, Lalithambika S, Sadder M, Saleh A, Fromm M, Riethoven JJ, Lu G, Avramova Z