Over the past decade we used genetic manipulations to study the contribution of GABAergic interneurones for rhythmic synchronous activity. We focused on the hippocampus on the medial entorhinal cortex, two brain structures that are crucially involved in spatial coding and spatial memory. Genetic manipulations included ablations of glutamate receptors or electrical coupling in GABAergic interneurones in the whole forebrain, or locally in the hippocampal‑entorhinal formation. Our studies underline the functional role of local GABAergic interneurones for spatial or temporal coding in the hippocampus. The genetic manipulations were always associated with distinct spatial memory deficits. These results will be summarized and discussed in the context of current models of memory formation and storage. In addition, I will present data demonstrating the presence of long-range GABAergic cells that connect the hippocampus and entorhinal cortex reciprocally. Also these data will be discussed in a larger context, since there is good reason to believe that long-range GABAergic neurones are more abundant in the forebrain as previously thought. Most recent studies in the lab focus on long-range GABA that connect several cortical areas involved in pain perception. By virtue of their connectivity – the target cells are most often local interneurones – this class of cells is ideally suited to synchronize brain regions over long distance.
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Robust and reproducible protoplast-to-plant systems are crucial for underpinning genetic manipulation technology involving somatic hybridisation and transformation. Novel and effective approaches for maximising the efficiency of such protoplast cultures include supplementation of media with surfactants and artificial gas carriers, such as perfluorochemicals and haemoglobin. Physical parameters, particularly electrostimulation, also enhance the development of protoplasts and protoplast-derived cells in cullure. DNA uplake into protoplasts is now a routine and universally accepted procedure in plant biotechnology for introducing and evaluating both short-term (transient) and long-term (stable) expression of genes in cells and regenerated plants. Imporlantly, protoplast fusion overcomes pre- and post-zygotic sexual incompatibility barriers and generates novel germplasm through new nuclear-cytoplasmic combinations. In this respect, considerable progress has been made in generating somatic hybrid plants, particularly in citrus, brassicas and polato. Isolated protoplasts are also a unique single cell syslem for evaluating aspects of ultrastructure, genetics and physiology, with potential for the biosynthesis of novel secondary products, including commercially-important recombinant proteins (e.g. antibodies), and as systems in toxicity screening. Recent advances in protoplast technology have benefited from advances in animal and microbial cell culture, with interesting parallels existing between these systems. Further innovations will necessitate the strengthening of interdisciplinary links in these research fields and the requirement for continued dialogue and cooperation between workers with diverse but complementary skills.