From: 01.01.1981 - 31.01.2010
Our research team was involved in the identification and characterization of renal proximal tubular and small intestinal transport systems, mostly luminal (brush border membrane) sodium/solute-cotransport systems. At first, we have studied their functional propertis in isolated brush border membrane vesicles and later also in tissue culture cells. Later on, we have identified the different genes encoding these transport systems, mostly by using oocyte expression clonig strategies (for example: Na/sulphate- and Na/phosphate-cotransporters (NaSi’s and NaPi’s). By using the related molecular probes we have studied molecular mechanisms involved in pysiological and pathophysiological alterations of proximal tubular and small intestinal absorption/reabsorption of phosphate and sulphate. Finally, we have also analyzed in heterologous expression systmes (mostly ooctyes) the kinetic properties of NaPi’s and have made first attempts towards an analysis of ‚structure/function relationships’ by using site directed mutagenesis approches and electrophysiological, tracer and optical techniques.