About the Authors
Department of Cell Biology, Duke University Medical Center, Durham, North Carolina, United States of America
The authors have declared that no competing interests exist.
Conceived and designed the analysis: SAJ AN BC. Provided input in writing the manuscript: AN DMM LM SCM. Conceived and designed the experiments: BC. Performed the experiments: SAJ JC TD DMM. Analyzed the data: SAJ AN. Wrote the paper: SAJ BC.