Nat Commun 2015 Mar 16;6:6517. Epub 2015 Mar 16.
1] Department of Animal Biology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA [2] Cell and Molecular Biology Graduate Program, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA [3] Center for Molecular Studies in Digestive and Liver Diseases, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA [4] Department of Cell and Developmental Biology, School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA [5] Institute for Regenerative Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA.