Fig. 4

piRNAs are required for telomere localization at nuclear periphery. a DNA FISH with HeT-A (green) combined with Rhi staining (red) was performed on ovaries of the yw strain and of the spn-E¹/spn-E^hls3987 mutants. b Estimation of the positioning of clustered HeT-A signals relative to the nuclear surface of nurse cells by 3D quantitative confocal image analysis of HeT-A DNA FISH on ovaries of spnE/+, spn-E¹/spn-E^hls3987, piwi/+, and piwi²/piwi^Nt mutants. c piRNAs are dispensable for telomere capping and telomere clustering. DNA FISH with HeT-A probe combined with HOAP staining was performed on ovaries of the yw and spn-E¹/spn-E^hls3987 strains. d Double DNA FISH with HeT-A (red) and TART (green) probes was performed on ovaries of the yw strain. e, f piRNA pathway disruption causes loss of Rhi from TART but not from the 42AB piRNA cluster. DNA FISH (green) with TART-A (e) or 42AB (f) probes combined with Rhi staining (red) was performed on ovaries of the yw and spn-E¹/spn-E^hls3987 strains. DNA is stained with DAPI (blue). Nuclei of nurse cells from VIII to X stages of oogenesis are shown