Systems Biology Lab, Institut Pasteur, 75724 Paris Cedex 15, France and Department of Systems Biology, Columbia University, New York, NY 10032, USA.|Systems Biology Lab, Institut Pasteur, 75724 Paris Cedex 15, France and Department of Systems Biology, Columbia University, New York, NY 10032, USA.|Systems Biology Lab, Institut Pasteur, 75724 Paris Cedex 15, France and Department of Systems Biology, Columbia University, New York, NY 10032, USA.|Systems Biology Lab, Institut Pasteur, 75724 Paris Cedex 15, France and Department of Systems Biology, Columbia University, New York, NY 10032, USA.|Systems Biology Lab, Institut Pasteur, 75724 Paris Cedex 15, France and Department of Systems Biology, Columbia University, New York, NY 10032, USA.