Research Areas

Voltage-gated sodium channels (Na_V channels) initiate action potentials and play therefore a key role in the electrical signalling of excitable cells. Various venomous animals target Na_V channels with specific neurotoxins. Some of these neurotoxins suppress the function of Na_V channels, while others enhance their activity. We investigate the different modes of operation of such neurotoxins from scorpions and cone snails on a molecular level and try to evaluate their therapeutic potential. Furthermore, we study the molecular mechanisms of Na_V channel function and their involvement in human diseases.

Ion channels often show increased activity in tumour cells. This led to the hypothesis that aberrant activity of ion channels can support cancer formation and progression. In co-operation with clinical groups we examine expression patterns and functional activities of potassium channels in human tumours (e.g. melanoma, neuroblastoma, glioma). A central aim of this work is the identification of new therapeutic targets for cancer treatment.

Reactive Oxygen Species (ROS) occur during normal metabolic activity but they are generated at particularly high concentrations under certain pathophysiological conditions. ROS can posttranslationally modify proteins, often leading to a loss of function. We investigate how ion channels are modulated by oxidative processes. Furthermore, our interest is focused on enzymes capable of "repairing" proteins previously oxidized at methionine residues - methionine sulfoxide reductases, and their involvement in the process of ageing.

Potassium channels are involved in many cellular processes, and drugs can affect their activity. This can be utilized for treating disease, but can also cause undesired side effects of drugs. Using biochemical and electrophysiological techniques we investigate the molecular mechanisms of pharmacological modification of potassium channels. We aim to learn more about binding sites and mechanisms of action of channel blockers and activators and to gain insight into the molecular mechanisms and principles of ion channel function.

In the section of biophotonics we investigate procedures by which by means of photons cell functions are manipulated and how information about cells and proteins are obtained. Based on green fluorescent proteins (GFP) we develop sensors for oxidative protein modifications and intracellular signalling molecules. We investigate how upconverting nanoparticles can be employed as light sources of molecular dimension in a biological setting. Furthermore, we study how the membrane potential of cells is manipulated by means of targeted photonic excitation.