Metabolism
- Lysine metabolism cross-regulates the cellular energy status of plants
- Regulation of aromatic amino acids metabolism in plants
- A Novel bioinformatics tool to study the regulation of branched metabolic pathways
- A dynamic community of plant metabolism: http://metwork.weizmann.ac.il
Autophagy
- Novel plant proteins associated with Autophagy
Amino acids Metabolism
Lysine metabolism cross-regulates the cellular energy status of plants
We found that boosting up lysine synthesis together with blocking its degradation causes a major reduction in the TCA cycle metabolites, exposing a metabolic link between lysine metabolism and energy regulation.
The AGD-2 Arabidopsis mutant displays a reduced flux of lysine biosynthesis due to a point mutation in a lysine biosynthetic enzyme. This mutation reduces the efficiency of plant growth, and also reduces significantly the level of the TCA cycle metabolite citric acid and the regulatory metabolites inositol and threhalose.
Regulation of phenylalanine metabolism in plants
Phenylalanine (Phe) is a highly important amino acid in plants being a precursor for thousands of secondary metabolites that are important for plant growth and for human health. Expression of a bacterial gene encoding the first two enzymes of Phe biosynthesis (Fig. 4; two red arrows) stimulates the production of Phe and a number of Phe-derived secondary metabolites in Arabidopsis plants (Fig. 5).
The PheA gene, which synthesizes phenylpyruvate, may also boost the production of metabolites associated with aroma and flavor.
A dynamic community of plant metabolism
We developed the “Metwork” website in order to establish a dynamic community whose main focus is plant metabolism http://metwork.weizmann.ac.il
A Novel bioinformatics tool to study the regulation of branched metabolic pathways
Gene expression programs associated with enzymes of branched metabolic networks are difficult to study because such genes may be either positively or negatively regulated under different conditions in which either both branches are active or one is active and one is suppressed, respectively (see diagram on the right depicting genes 1 and 2, which regulate in a concerted manner the conversion metabolite X either to metabolite Y or to metabolite Z or to both metabolites Y and Z together).
We developed a special bioinformatics tool to study gene expression networks associated with branch metabolic pathways and currently use it to study coordinated expression networks of genes encoding the entire set of transcription factors and metabolite enzymes in Arabidopsis plants.
Novel plant proteins associated with Autophagy
Autophagy is a multifunctional cell biology process associated with growth and response to various environmental and physiological stresses. We have identified three plant-specific proteins (called AAP1 - AAP-3) that interact with Atg8f, a central multifunctional protein in the autophagy machinery. AAP1 appears to be localized to the nucleus that is surrounded by endoplasmic reticulum. It functions in the nucleus are still not known.