Joint Center for Structural Genomics, La Jolla, CA 92037, USA. wchwang@sanfordburnham.org.|Joint Center for Structural Genomics, La Jolla, CA 92037, USA. wchwang@sanfordburnham.org.|Joint Center for Structural Genomics, La Jolla, CA 92037, USA. wchwang@sanfordburnham.org.|Joint Center for Structural Genomics, La Jolla, CA 92037, USA. wchwang@sanfordburnham.org.|Joint Center for Structural Genomics, La Jolla, CA 92037, USA. wchwang@sanfordburnham.org.|Joint Center for Structural Genomics, La Jolla, CA 92037, USA. wchwang@sanfordburnham.org.|Joint Center for Structural Genomics, La Jolla, CA 92037, USA. wchwang@sanfordburnham.org.|Joint Center for Structural Genomics, La Jolla, CA 92037, USA. wchwang@sanfordburnham.org.|Joint Center for Structural Genomics, La Jolla, CA 92037, USA. wchwang@sanfordburnham.org.|Joint Center for Structural Genomics, La Jolla, CA 92037, USA. wchwang@sanfordburnham.org.|Joint Center for Structural Genomics, La Jolla, CA 92037, USA. wchwang@sanfordburnham.org.|Joint Center for Structural Genomics, La Jolla, CA 92037, USA. wchwang@sanfordburnham.org.|Joint Center for Structural Genomics, La Jolla, CA 92037, USA. wchwang@sanfordburnham.org.