A DEMETER-like DNA demethylase protein governs tomato fruit ripening

In plants, genomic DNA methylation which contributes to development and stress responses can be actively removed by DEMETER-like DNA demethylases (DML). Indeed, in Arabidopsis DMLs are important for maternal imprinting and endosperm demethylation, but only few studies demonstrate the developmental roles of active DNA demethylation conclusively in this plant. Here we show a direct cause and effect relationship between active DNA demethylation mainly mediated by the tomato DML, SlDML2, and fruit ripening; an important developmental process unique to plants. RNAi SlDML2 knock-down results in ripening inhibition via hypermethylation and repression of the expression of genes encoding ripening transcription factors and rate-limiting enzymes of key biochemical processes such as carotenoid synthesis. Our data demonstrate that active DNA demethylation is central to the control of ripening in tomat

Influence des fluctuations lumineuses sur le metabolisme photosynthetique et la productivite de diatomees temperees et antarctiques en culture

CNRS T Bordereau / INIST-CNRS - Institut de l'Information Scientifique et TechniqueSIGLEFRFranc

Metabolic engineering of Isoprenoid biosynthesis

Isoprenoids constitute one of the largest families of natural compounds. They play essential functions in plant growth and development and furnish compounds of high interest for humans. Here, we present the current knowledge on isoprenoid metabolism before describing the strategies that have been used for isoprenoid metabolic engineering. We discuss the advantages and drawbacks of using microorganisms and plants as cell platform for the production of isoprenoids of interest