Fig. 2
Development of Vmem-gradients in the FCE during S8–12 (DiBAC; SIM). a Schematic drawing of a S10b-follicle placed between an object slide and a cover slip. The focal plane of median optical sections generated by the ApoTome (SIM) is shown as dashed green line. b Schematic drawing of an ovariole showing Vmem in the analysed stages S8–12 (cf. Additional file 1: Figure S2 for examples). c During S9–12, an a-p gradient establishes with relatively hyperpolarised cFC and relatively depolarised pFC. From S10b onwards, a d-v gradient with relatively depolarised vFC and relatively hyperpolarised dFC develops (cf. Additional file 2: Table S2). For abbreviations and statistics, see legend to Fig. 1. d Optical median sections of a DiBAC-stained S10b-follicle. Inset shows a pseudocolour image of the same section. Low fluorescence intensity (green) indicates relative hyperpolarisation while high fluorescence intensity (red) indicates relative depolarisation