ETH Zurich, Institute of Molecular Systems Biology, Wolfgang-Pauli Strasse 16, 8093 Zurich, Switzerland. zamboni@imsb.biol.ethz.ch|ETH Zurich, Institute of Molecular Systems Biology, Wolfgang-Pauli Strasse 16, 8093 Zurich, Switzerland. zamboni@imsb.biol.ethz.ch|ETH Zurich, Institute of Molecular Systems Biology, Wolfgang-Pauli Strasse 16, 8093 Zurich, Switzerland. zamboni@imsb.biol.ethz.ch