Faculty of Computer and Information Science, University of Ljubljana, Trzaska 25, SI 1000 Ljubljana, SI, Slovenia. uros.lotric@fri.uni-lj.si.|Faculty of Computer and Information Science, University of Ljubljana, Trzaska 25, SI 1000 Ljubljana, SI, Slovenia. uros.lotric@fri.uni-lj.si.|Developmental Biology, Sloan-Kettering Institute, 1275 York Avenue, New York, New York 10065, USA. baoz@mskcc.org.