Figure 1.

Overall structure of Polϵ p59–p261_C. A, schematic representation of the domain organization. The dark blue lines in the schematics of p261_C present the relative positions of the zinc-coordinating residues in two zinc-binding modules: Zn1 (Cys²¹⁵⁸, Cys²¹⁶¹, Cys²¹⁸⁷, and Cys²¹⁹⁰) and Zn2 (Cys²²²¹, Cys²²²⁴, Cys²²³⁶, and Cys²²³⁸). B, stereo view of p59–p261_C. p261_C is colored light pink; the PDE domain (excluding region 84–121) and OB domain are colored cyan and green, respectively. The N-terminal portion of the PDE domain (residues 84–121) is colored red. Zinc atoms are depicted as dark blue spheres.