Nature Communications 5: Article number: 4525 (2014); Published: 31 July 2014; Updated: 4 March 2015

The affiliation details for Jie Yan are incorrect in this Article. The correct affiliation details for this author are given below:

Mechanobiology Institute, National University of Singapore, Singapore 117411, Singapore.

Department of Physics, National University of Singapore, Singapore 117542, Singapore.

Singapore-MIT Alliance for Research and Technology, National University of Singapore, Singapore 117543, Singapore.

Centre for Bioimaging Sciences, National University of Singapore, Singapore 117546, Singapore.