Figure 5
Functional role of the pre-S1 domain/shoulder. (A) Averaged traces of TRPC6 currents induced by CCh (100 μM). Black: TRPC6WT, blue: R437Q mutant. Light gray and blue regions indicate SEM. (B) Summary of receptor-operated current densities obtained with various TRPC6 mutants (n > 5). (C) Ca2+-dependent inactivation. Representative traces for the CCh response in TRPC6WT (black) and R437Q (blue) under the low Ca2+ buffering condition (1 mM EGTA in the intracellular solution). R437Q trace was scaled to match WT traces (at scale with bar). Residual currents after the peak show identical inactivation profiles with the TRPC6WT (right panel, black circles), the pre-S1 mutants (R437Q (n = 7), and R437/K442Q (n = 5) for blue and green triangles, respectively. (D) Confocal microscopic analysis of the distribution of pre-S1 mutants. Left: CFP-fused channel. Middle: YFP-fused PH domain. Right: Merged images. Pearson’s correlation coefficient (n > 10). *p < 0.05 or **p < 0.01.
