Project description:Our goal is to identify Salycilic Acid responsive genes dependent on PLD activation. - The experiment is done on Arabidopsis suspension cells, ecotype Columbia : Research of phospholipase D (PLD) activity implication in the response to SA. The use of primary alcohol, like N-butanol, makes possible to derive PLD activity towards the production of phosphatidylalcohol with the detriment of phosphatidic acid, the product of the PLD. Thus, in the presence of n-butanol, the response of the genes to SA dependent on phosphatidic acid will see their response disturbed. On the contrary, in the presence of tertiary butanol, the response of the genes should not be disturbed, tertiary alcohols not acting on the PLD. Keywords: treated vs untreated comparison
Project description:PHOSPHATIDIC ACID PHOSPHOHYDROLASE (PAH) catalyses the conversion of phosphatidic acid to diacylglycerol. Disruption of two gene encoding this enzyme in Arabidopsis thaliana results in increased phosphatidylcholine synthesis and proliferation of the endoplasmic reticulum (Eastmond et al., [2010] Plant Cell 22: 2796). We performed microarray analysis on two week old wild type Arabidopsis plants and the pah1 pah2 double mutant using the Ath1 chip to determine what effect the double mutation has on global gene expression.
Project description:au10-12_pa - phosphatidic acid in gene expression - Role of DGK in gene expression - Compounds were added 4h before cell harvesting.
Project description:au10-12_pa - phosphatidic acid in gene expression - Role of DGK in gene expression - Compounds were added 4h before cell harvesting. 6 dye-swap - treated vs untreated comparison
Project description:Plants depend on photosynthesis as their primary means to generate energy and building blocks, and adverse environmental conditions can stress the photosynthetic apparatus leading to the production of toxic byproducts. In the long term, stress experienced by the chloroplast must be communicated to the nucleus to adjust the expression of genes providing robust abiotic stress resilience in a process called retrograde signaling. We propose a retrograde signaling mechanism that starts with the accumulation of phosphatidic acid at the outer chloroplast membrane. A mutant of Arabidopsis thaliana, lppγ lppɛ1, disrupted in two chloroplast envelope membrane-located phosphatidic acid phosphatases shows reduced growth and activation of abscisic acid-mediated abiotic stress response pathways, among other changes, as determined by RNA-Seq analysis. The mutant is more resistant to freezing and osmotic stress. To identify components of the proposed retrograde signaling pathway, we conducted a suppressor screen in the lppγ lppɛ1 mutant and identified a mutation that causes the loss of MED16, which is a component of Mediator, a transcriptional complex in the nucleus affecting the expression of genes involved in freezing tolerance, among others. Based on these findings we are proposing a lipid-based, retrograde signaling mechanism in response to abiotic stresses such as freezing.
