Figure 9. Mutation of Arg178 in Kir5.1 eliminated the effect of PIP2 on channel sensitivity to pHi. In the tandem dimer of Kir4.1âKir5.1, site-specific mutations were made at Lys67 in Kir4.1 and Arg178 in Kir5.1. Inward-rectifying currents were then studied in inside-out patches in the absence or presence of PIP2 (10 μM). The R178Q mutant showed pHi sensitivity similar to the wild-type Kir4.1âKir5.1 with pK 7.50. Its pHi sensitivity was identical with or without PIP2 in the internal solution. The double mutant (K67M/R178Q) showed the pHi sensitivity (pK 7.15) similar to the Kir4.1âKir5.1 with a single K67M mutation. Such pH sensitivity was not affected by PIP2.
Image published in: Yang Z et al. (2000)
© 2000 The Rockefeller University Press. Creative Commons Attribution-NonCommercial-ShareAlike license
Permanent Image Page
Printer Friendly View
XB-IMG-121419