Figure 1.
Domain structure and expression profile of cGMP-indicators. (A) N-terminal cGPK deletion mutants: Δ1–77 (cygnet-1) lacks the dimerization and autoinhibitory domain; Δ1–77/Thr516Ala (cygnet-2) represents the catalytically inactive mutant. Δ1–109 begins with the high-affinity cGMP binding site and Δ1–227 retains the low-affinity cGMP binding site. (B) C-terminal cGPK deletion mutants: Δ336–670, Δ340–670, Δ352–670, and Δ357–670 deletions have the catalytic domain and successive portions of a putative α-helix (W.R.G.D., unpublished results) eliminated.