Fig. 1: Structural basis for the selectivity of cp1 to BCL-2.
a 3D structure model of cp1 with its residue sequence shown around the cycle. The residues not directly involved in the cp1-protein interactions are shown in red. The overall binding positions of cp1 upon BCL-2 (b) and BCL-XL (c). BCL-2 and BCL-XL proteins are shown as surface in limon (b) or white (c), with their α-helices near the binding groove labeled; and cp1 is shown as sticks in purple (b) or magenta (c). d Superposition of BCL-2 and BCL-XL in complex with cp1. Colors are the same as in panels b and c. All 7 α-helices of two proteins surrounding cp1 are labeled accordingly. e Comparison of key amino-acid residues within 5 Å around cp1 in BCL-2 and BCL-XL. Two pairs of non-conserved residues, D111/M115 of BCL-2 and A104/L108 of BCL-XL are shown as sticks in green and cyan, respectively. Key residues of cp1 interacting with BCL-2 (f) or BCL-XL (g) in two different views.
