About the Authors

Paula Stein

Affiliation Department of Biology, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America

Nikolay V. Rozhkov

Affiliation Cold Spring Harbor Laboratory, Watson School of Biological Sciences and Howard Hughes Medical Institute, Cold Spring Harbor, New York, United States of America

Fan Li

Affiliation Department of Biology, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America

Fabián L. Cárdenas

Affiliation Department of Biology, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America

Olga Davydenk

Affiliation Department of Biology, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America

Lee E. Vandivier

Affiliation Department of Biology, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America

Brian D. Gregory

Affiliation Department of Biology, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America

Gregory J. Hannon

Affiliations Cold Spring Harbor Laboratory, Watson School of Biological Sciences and Howard Hughes Medical Institute, Cold Spring Harbor, New York, United States of America, CRUK Cambridge Institute, Li Ka Shing Centre, University of Cambridge, Cambridge, United Kingdom

Richard M. Schultz

rschultz@sas.upenn.edu

Affiliation Department of Biology, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America

Competing Interests

The authors have declared that no competing interests exist.

Author Contributions

Conceived and designed the experiments: PS BDG GJH RMS. Performed the experiments: PS NVR FLC OD. Analyzed the data: PS NVR FL LEV BDG GJH RMS. Wrote the paper: PS GJH RMS.