About the Authors
Laboratory of Genetics, University of Wisconsin – Madison, Madison, Wisconsin, United States of America
Department of Cell and Developmental Biology, University of Pennsylvania Medical School, Philadelphia, Pennsylvania, United States of America
The authors have declared that no competing interests exist.
Conceived and designed the experiments: TY RL FP. Performed the experiments: TY XG RL SN FP. Analyzed the data: TY RL SN FP. Contributed reagents/materials/analysis tools: TY XG RL GR MCM. Wrote the paper: SN FP.