He could have pursued many careers and would have been happy: “A pathologist, for example. Or an architect”, says Christoph Fahlke. Instead, he has become a “channel worker”, which is by no means meant to sound derogatory: “There are worse labels,” says the director of the Institute of Complex Systems (ICS-4) and laughs. Ion channels and ion transporters have fascinated the 54-year-old for decades: “These proteins are located in the cell membrane and serve as gates for the transport of different ions into or out of the cell. These processes are vital for our organism,” explains the professor of biophysics. Malfunctions can lead to diseases such as epilepsy or high blood pressure.

He could have pursued many careers and would have been happy: “A pathologist, for example. Or an architect”, says Christoph Fahlke. Instead, he has become a “channel worker”, which is by no means meant to sound derogatory: “There are worse labels,” says the director of the Institute of Complex Systems (ICS-4) and laughs. Ion channels and ion transporters have fascinated the 54-year-old for decades: “These proteins are located in the cell membrane and serve as gates for the transport of different ions into or out of the cell. These processes are vital for our organism,” explains the professor of bio-physics. Malfunctions can lead to diseases such as epilepsy or high blood pressure. is organised in such a way that there are many independent working groups, mine is the largest, and I am very active in leading them – management-only work does not suit me,” says the institute director. He is also interested in too many things at that.

He received his doctorate in medicine from Ulm University in 1990, was awarded the prize for the best medical doctorate there in 1991, and received his licence to practise as a physician in 1992. At the same time, he was writing his diploma thesis in physics and working on chloride channels in a physiology laboratory, which are important for the functions of nerve cells and muscle cells, for the first time. He was un­aware that the course of his life was to be set here: since then, electrophysiology as a subfield of neurophysiology has not only accompanied him: “It actually makes me happy. I keep telling my doctoral students that they should know as many techniques as possible, but they need one that is near and dear to them – that’s what electrophysiology is for me.” This includes the Nobel Prize-winning patch-clamp method, which allows small electrical currents flowing through ion channels in a cell membrane to be measured. Even individual ion channels can be observed this way as they open and close – like small gates. “There are few things so beautiful,” Fahlke raves.

THREE DISEASES IN FOCUS

Although many other techniques have long since found their way into Fahlke’s scientific everyday life, electrophysiology is still playing a central role: his group uses patch clamping to examine defective ion channels or ion transporters that are associated with three diseases. “We do research on neurological diseases in which the coordination of movement is disturbed for a short time, on epilepsy and on a certain form of hypertension,” explains the scientist. All three disease patterns are monogenetically determined diseases. This means that there is a direct connection between a deficient ion channel and an organ malfunction – much unlike complex diseases such as cancer, arteriosclerosis or Alzheimer’s disease. As recently as at the beginning of this year, his team was involved in an international publication presenting the disease mechanisms of a special form of hypertension. The Jülich researchers were able to show for the first time how a certain ion channel protein regulates blood pressure.

After working at RWTH Aachen University and Hannover Medical School, Fahlke has been living with his family in Jülich since 2012. This was exactly the right step for the former Heisenberg scholarship holder and Asia lover. “Forschungszentrum Jülich affords me many experimental approaches. I can have every protein function that comes to my mind measured at our institute or at a neighbouring institute, or I can measure it myself.” The variety of disciplines in Jülich and the cooperation with various universities in the region is also a great advantage of the location: “You find a contact person for every problem,” says the biophysicist. And this is where things come full circle: even though he once decided to become a medical doctor, Forschungszentrum Jülich offers him a platform to work with many other professions.

Katja Lüers