1. Genomics Research Center, Academia Sinica, Taipei 115, Taiwan
2. Department of Chemistry, National Taiwan University, Taipei 106, Taiwan
3. Institute of Biochemical Sciences, National Taiwan University, Taipei 106, Taiwan
4. Department of Chemistry, The Scripps Research Institute, La Jolla, California 92037, United States
5. Institute of Cellular and Organismic Biology, Academia Sinica, Taipei 115, Taiwan