Xenbase Image ID: 170623

Figure 3. Characterization of the voltage-dependent potassium current induced by XShal transcripts. A, Currents induced by expression of XShal (top) or XSha2 (bottom) RNA in oocytes were elicited by depolarizing steps to voltage levels ranging between -50 to +60 mV from a holding potential of -80. The XShal-induced current begins to activate at -40 mV and is sustained for the duration of the 60 msec pulse, indicating that is a delayed-rectifier-like current. XSha2 RNA induces a delayed-rectifier potassium current, which has a voltage dependence of activation that is depolarized with respect to XSha 1. Calibration: 2 PA, 10 msec. B, Conductance density-voltage plots compare the voltage dependence of activation of XShal- and XShaZ-induced currents in oocytes to that of the endogenous delayed rectifier (I,“) and A potassium currents (I& recorded from primary spinal neurons (after Ribera and Spitzer 1989, 1990). Oocyte current densities were calculated assuming a cell diameter of 1 mm. The endogenous delayed-rectifier current has activation properties that are more similar to that of XSha2. Recordings were done in standard solution. Image published in: Ribera AB and Nguyen DA (1993) Copyright © 1993. This image is reproduced with permission of the publisher and the copyright holder. This is an Open Access article distributed under the terms of the Creative Commons Attribution License. Larger Image Printer Friendly View

Return to previous page