Program in Molecular and Computational Biology, University of Southern California, Los Angeles, CA, USA.|Program in Molecular and Computational Biology, University of Southern California, Los Angeles, CA, USA.|Program in Molecular and Computational Biology, University of Southern California, Los Angeles, CA, USA.|Program in Molecular and Computational Biology, University of Southern California, Los Angeles, CA, USA.|Program in Molecular and Computational Biology, University of Southern California, Los Angeles, CA, USA.