Journal: The FASEB Journal
Article Title: Structural basis for the antiarrhythmic blockade of a potassium channel with a small molecule
Figure Lengend Snippet: F255A and D260A mutations reduce the ability of chloroquine to block I KACh . A ) Confocal microscopy. Fluorescence staining of I KACh proteins. Top) Live HEK293 cells transfected with mCherry, WT Kir3.1, and Kir3.4. Middle (bottom): cells transfected with mCherry, Kir3.1 F255A or D260A, and Kir3.4, where tertiapinQ ATTO-488 showed robust staining of the cell membranes. B ) BaCl 2 -sensitive I KACh currents elicited in WT Kir.31/Kir3.4-, F255A Kir3.1/Kir3.4-, or D260A Kir3.1/Kir3.4-transfected cells, in response ramps from −140 to +30 mV, before and after addition of 1 μM CQ. C, left: Dose-response curves for the effect of chloroquine on the BaCl 2 -sensitive inward current measured at −120 mV. IC 50 for WT: 0.8 μM, R 2 = 0.81, n = 11; F255A: 3.2 μM, R 2 = 0.75, n = 10; and D260: 2.8 μM, R 2 = 0.9, n = 10. P
Article Snippet: For fluorescence imaging, cells were plated on a coverslip and stained for 10 s with tertiapinQ-ATTO-488 (Alomone Laboratories, Jerusalem, Israel), and then images were acquired using an Olympus FV1000 multiphoton laser-scanning microscope.
Techniques: Blocking Assay, Confocal Microscopy, Fluorescence, Staining, Transfection