About the Authors
Temasek Life Sciences Laboratory, National University of Singapore, Singapore
Department of Biological Sciences, National University of Singapore, Singapore
The authors have declared that no competing interests exist.
The author(s) have made the following declarations about their contributions: Conceived and designed the experiments: PCC WC YC. Performed the experiments: PCC ZL. Analyzed the data: PCC WC YC. Contributed reagents/materials/analysis tools: PCC ZL WC YC. Wrote the paper: PCC WC YC.