1. Genomics Research Center, Academia Sinica, 128 Academia Road, Section 2, Nankang, Taipei 115, Taiwan, Institute of Biochemistry and Molecular Biology, National Yang-Ming University, Taipei 112, Taiwan, Chemical Biology and Molecular Biophysics, Taiwan International Graduate Program, Academia Sinica, Taiwan, Institute of Bioinformatics and Structural Biology, National Tsing-Hua University, Hsin-Chu 300, Taiwan and Institute of Biochemical Sciences, National Taiwan University, Taipei, Taiwan