About the Authors

Jessica L Feldman

Affiliation Department of Biochemistry and Biophysics, University of California San Francisco, San Francisco, California, United States of America

Stefan Geimer

Affiliation Biologie/Elektronenmikroskopie NW I/B 1, Universität Bayreuth, Bayreuth, Germany

Wallace F Marshall

To whom correspondence should be addressed. E-mail: wmarshall@biochem.ucsf.edu

Affiliation Department of Biochemistry and Biophysics, University of California San Francisco, San Francisco, California, United States of America

Competing Interests

The authors have declared that no competing interests exist.

Author Contributions

JLF and WFM conceived and designed the experiments and contributed reagents/materials/analysis tools. JLF and SG performed the experiments and analyzed the data. JLF wrote the paper.