Silica is a unique biological material in the sense that it is not soluble within the tissue and its deposition is irreversible. Nevertheless the chemical condition for its deposition and the deposition location seem to be loosely controlled sometimes. This situation is untypical to biological systems. We use a combination of material sciences approach and genetic manipulations methods to study the bio-mineralization of this enigmatic material.
Plants produce thousands of different compounds helping them in adapting to changing environmental conditions. These so-called ??secondary metabolites?? are formed during plant development as well as upon diverse endogenous and environmental stimuli. Human beings encounter such compounds in their daily life as for example food flavors, color dyes, perfumes, scented oils and industrial products such as rubber and oils.
Asaph Aharoni recently set-up a new group which investigates regulatory networks controlling the biosynthesis of these compounds in the course of plant development and under stress conditions. New tools are currently being developed in the lab which will allow extensive metabolic profiling and the integration of metabolic data with information derived from other levels of regulation such as the transcriptome. This type of research activity requires a multidisciplinary approach combining molecular biology and chemistry.
During the period in our lab the student will acquire know-how either in molecular biology or analytical chemistry techniques to study a particular plant genotype, mutant or transgenic line. The student could also combine and experience both research fields.
We study the regulation of several key metabolic pathways in plants including:
A. The isoprenoid biosynthesis pathway that generates carotenoids (among them the compound lycopene that provides tomato its red color) in the course of tomato fruit ripening.
B. The shikimate pathway that directs carbon flow towards the biosynthesis of the three aromatic amino acids, phenylalanine, tryptophan and tyrosine. These three amino acids are the most important precursors for the production of secondary metabolites in plants.
C. The metabolic pathways leading to the formation of the four group of metabolites that make up the plant outer surface constituent, the cuticle. We study the regulation of plant surface pathways in both vegetative tissues (in the model plant Arabidopsis) and in reproductive organs (in tomato fruit peel).