Figure 4. Sensitivity of nvTRPM2 chimeras with alternative NUDT9 domains to intracellular ADPR and extracellular H₂O₂.

(a) Average data of whole-cell patch clamp experiments where nvTRPM2-NUDenz (nvTRPM2 with NUDT9 domain of the hNUDT9 enzyme) or nvTRPM2-hNUD (nvTRPM2 with NUDT9 domain of hTRPM2) were stimulated either with 50 μM ADPR in the pipette solution (intracellular Ca²⁺-concentration ≤10 nM) or by extracellular application of 10 mM H₂O₂ (intracellular 1 μM Ca²⁺). **Indicates a significant difference (P = 0.01) from Student's t-test. n = 5–8. Error bars are s.e. (b)–(e) Representative recordings showing current development of nvTRPM2-NUDenz (b, c) and nvTRPM2-hNUD (d), (e) after stimulation with ADPR or H₂O₂ as indicated. During stimulation with ADPR, the experiments were started in divalent-free bath solution (DVF) and currents only developed after substitution of DVF with standard bath solution with 1.2 mM Ca²⁺.