Department of Biological Sciences, Molecular and Computational Biology Program, University of Southern California, 1042 West 36th Place, Los Angeles, CA 90089-1113, USA.|Department of Biological Sciences, Molecular and Computational Biology Program, University of Southern California, 1042 West 36th Place, Los Angeles, CA 90089-1113, USA.|Department of Biological Sciences, Molecular and Computational Biology Program, University of Southern California, 1042 West 36th Place, Los Angeles, CA 90089-1113, USA.|Department of Biological Sciences, Molecular and Computational Biology Program, University of Southern California, 1042 West 36th Place, Los Angeles, CA 90089-1113, USA.