Figure 5. Sensitivity of nvTRPM2 variants with point mutation or deletion within the NUDT9 domain to intracellular ADPR and extracellular H₂O₂.

(a) Average data of nvTRPM2 variants either containing the point mutation Q1438R or a deletion of a stretch of 15 amino acid residues immediately downstream of the NUDIX box. Stimulation was performed with 50 μM intracellular ADPR or 10 mM extracellular H₂O₂ as described in Fig. 4. n = 4–9. (b)–(f) Representative recordings showing current development of nvTRPM2-Q1438R and nvTRPM2-(Δ15) after stimulation with ADPR (b), (c) or H₂O₂ (d), (e) as indicated. (f) Note the occurrence of spontaneous currents as well as the development of H₂O₂-induced repetitive currents in the variant nvTRPM2-(Δ15).