Physiological changes induced by gene overexpression in plant cell cultures : Characterization and statistical significance

Heterotrophic, dedifferentiated suspended cell cultures facilitates the control of stress homogeneity and the characterisation of the cells’ behaviourindependently of plant morphologies. Pathogenesis-related (PR) proteins of group 10 and especially their member PR-10a were reported to show induced gene expression or protein abundance caused by several biotic and abiotic stressors in diverse studies on a variety of plants, organs, tissues and developmental stages. But the mode of action of the PR-10a protein itself as well as the pathways it could interfere with are still less well explored Based on a set of heterotrophic dedifferentiated cell cultures of Solanum tuberosum cv. Désirée (wild-type and transgenic lines homologously overexpressing pr-10a) providing the main biological system to be analysed, this thesis discuss, beside an optimized vector-architecture, cryopreservation as a novel experimental framework for gathering information on GMO, the development of a method for collecting additional physiological data, and last but not least the elaboration of suitable software solutions for convenient data visualization and analysis are investigated. Especially, the concept of respiration measurements is shown to be a meaningful complement for the set of methods when examining phenotypes of heterotrophic dedifferentiated cell cultures. The novel method provides valuable information in situations not more common methods such as growth measurements and the investigated data analyses strategiesform the basis for a forthcoming freely available R package for the analysis of PM data, representative for respiration measurements resulting in longitudinal data sets. The availability of convenient and robust data exploration techniques via freely available software such as R will allow users to conduct in-depth data analyses that go significantly beyond the consideration of mere endpoint measurements and presence/absence calls.