International Network of Plant Abiotic Stress

Drastic changes in plant polyamine (PA) metabolism occur in response to abiotic stresses, but the biological relevance of PA accumulation under stress is so far largely unknown. WG4 aims at integrated analysis of functional relationships among genes involved in the PA metabolic network. Based on the biochemically established PA metabolic pathway, further data will be added with regard to metabolite levels, enzymatic activities, protein expression levels, coordinated gene expression as well as cross-talk with other protective agents and stress signalling components. This systems biology approach will then be used to design system perturbation strategies at genetic (e.g. gene knockouts or over-expressions), physiological (e.g. growth conditions), environmental (drought, salt and cold stress) levels, and the molecular and biochemical consequences of these perturbations will be studied. In WG4, thus further insights into the molecular mechanisms underlying the role of PA metabolic pathway in abiotic stress signalling are envisaged. WG4 focuses on the:

WG4.1 Identification of a set of molecular and metabolic markers for PA-mediated abiotic stress (drought, salt and cold) responses.

WG4.2 Assessment of genetic and metabolic variability in various Arabidopsis ecotypes and Tellungiela halophila with regard to polyamine responses to abiotic stress.

WG4.3 Physiological and biochemical characterization of Arabidopsis PA metabolic mutants and transgenics with respect to drought, salt and cold stress.

WG4.4 Analysis of global changes in gene expression in Arabidopsis PA mutants, transgenics plants and Tellungiela halophila, to assess the role of PAs in abiotic stress signalling (i.e. possible links with SnRK1 and SnRK2 AMP-activated kinases, MAPK, ABA signalling, etc. ) and to establish possible cross-talks with other osmo-protecting agents (i.e. proline).

WG4.5 Physiological and biochemical characterization of PA metabolism in relevant crop plants (i.e. tomato and potato) and trees (i.e. poplar). Exploitation of knowledge gained in breeding and selection of commercially valuable crop and tree species with improved adaptation to abiotic stress.

New members will be welcome to join these studies by contributing to the characterization of novel elements of stress signaling cascades, or joining the functional genomics, transcriptomics or metabolomics approaches, or by introducing novel approaches of identifying natural diversity of functions involved in these pathways, or working toward applying tools and technologies developed by the network partners. Thus, the present proposal provides a flexible framework open for new partners.