[1] Univ Chicago, Comm Neurobiol, Chicago, IL 60637 USA
[2] Univ Chicago, Dept Pediat, Chicago, IL 60637 USA
[3] US Naval Res Lab, Ctr Biomol Sci & Engn, Washington, DC 20375 USA
[4] US Naval Res Lab, Div Opt Sci, Washington, DC 20375 USA
[5] Scripps Res Inst, La Jolla, CA 92037 USA
[6] Univ Chicago, Dept Pediat, Chicago, IL 60637 USA
[7] Univ Chicago, Dept Biochem & Mol Biol, Chicago, IL 60637 USA