Fig. 6. SWI1 immunolocalization. (A) Three examples of meiotic cells expressing SWI1. (B) SWI1 is not detected at leptotene stage. (C) Diagrams outlining the three kinds of BrdU incorporation experiment. (D-I) Double localization of SWI1 and incorporated BrdU. In each panel, the upper picture shows a DAPI-stained nucleus (blue), the middle one the BrdU immunolocalization (green), and the lower one shows the SWI1 immunolocalization (red) on the same nucleus. (D) Experiment 1. Tissues were harvested directly at the end of the pulse. The cell shown is at S phase, according to the BrdU labeling, and expresses SWI1. (E-H) Experiment 2. Samples were harvested 2 hours, 6 hours or 10 hours after the end of the 2-hour pulse. After a 2-hour delay, half of the BrdU-positive cells express SWI1 (E) while the other half do not (F). After a 6-hour or a 10-hour delay, BrdU-positive cells do not express SWI1 (G-H). (I) Experiment 3. Samples were harvested at the end of an 8-hour BrdU treatment. Small meiotic cells express SWI1, and are BrdU negative, indicating they are in G₁. Scale bar: 10 µm.