Institute of Molecular and Cellular Biology, National Taiwan University, Taipei, Taiwan.|Institute of Bioinformatics and Structural Biology, National Tsing Hua University, Hsinchu, Taiwan.|Institute of Bioinformatics and Structural Biology, National Tsing Hua University, Hsinchu, Taiwan.|Institute of Molecular and Cellular Biology, National Taiwan University, Taipei, Taiwan.|Institute of Bioinformatics and Structural Biology, National Tsing Hua University, Hsinchu, Taiwan.