Xenbase Image ID: 126571

Figure 2. Aβ1–42 oligomers form Ca2+-permeable ion pores in the plasma membrane of Xenopus oocytes. (A) Representative image showing localized Ca2+ transients (SCCaFTs) imaged by TIRF microscopy during hyperpolarization to −100 mV within a 40 × 40–µm region of a vitelline-stripped oocyte loaded with fluo-4 dextran and EGTA. The imaging region was close to the edge of the footprint of the oocyte on the cover glass, and 1 µg/ml Aβ1−42 oligomers was applied to the bathing solution ∼18 min beforehand from a pipette positioned near the bottom right corner of the image frame. No activity was observed before application of Aβ1−42. The grayscale image of fluorescence ratio changes (ΔF/Fo; black = 0, white = 1.6) shows a mean of six consecutive video frames (2 ms per frame) from within a sequence of 15,000 frames. (B) Map showing the locations of all SCCaFTs (Aβ pores) identified during a 20-s recording from the membrane region in A. The map was automatically constructed by CellSpecks by identifying the coordinates of each SCCaFT. (C) Representative fluorescence profiles from regions of interest (1 µm2) centered on two pore locations. Image published in: Demuro A et al. (2011) © 2011 Demuro et al. This image is reproduced with permission of the journal and the copyright holder. This is an open-access article distributed under the terms of the Creative Commons Attribution-NonCommercial-ShareAlike license Larger Image Printer Friendly View

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