HA-GFP-TUT4 and HA-GFP-TUT7 fusion proteins were stained using the anti-HA (Covance, MMS-101P) antibody. Ovaries were collected and fixed in 4% formaldehyde overnight and embedded in paraffin. Sections of 6 μm thickness were stained as described previously35 (link). Free oocytes were fixed in 2% paraformaldehyde for 10 minutes and washed twice with 10% Normal Donkey Serum (NDS) (Sigma Aldrich), 0.1% BSA in PBS. Oocytes were then blocked with 10% NDS, 0.1 M Glycine and 2% BSA in PBS, permeabilized with 0.1% Triton X-100, 10% NDS, 0.1% BSA in PBS and washed again. The anti-β-tubulin (Sigma Aldrich, T4026) primary antibody and the Alexa Fluor Donkey (Invitrogen, A-21202) secondary antibody were used at 1:200 and 1:1000, respectively. DNA was stained with 5 μg/ml of Hoechst 33342 for 10 minutes at room temperature. Cells were mounted on slides for confocal microscopy. Images were acquired with a Leica TCS SP5 confocal microscope and Photoshop was used for cropping and other modifications that were equally performed on control and experimental samples.