About the Authors

Morgane Rolland
David C Nickle
James I Mullins

To whom correspondence should be addressed. E-mail: jmullins@u.washington.edu

Competing Interests

The authors have declared that no competing interests exist.

Author Contributions

JIM conceived and designed the experiments. MR, DCN, and JIM performed the experiments. MR, DCN, and JIM analyzed the data. MR and JIM wrote the paper.