Transcriptional profile of zebrafish eyes after exposure to 350 mg/L Propylthiouracyl (PTU)

Vertebrate eye devlopment is partially regulated by thyroid hormones. Propylthiouracyl is a pharmaceutical that lowers thyroid hormone levels. We investigated the effects of PTU on eye development of zebrafish. We expected PTU exposure to cause transcriptional changes of visual-system-related genes, which find their phenotypic anchoring in eye malformations and dysfunction, as observed in our previous studies. Additionally, the reversibility of effects after recovery in clean water for three days was investigated. We used an n + 2 A-optimal design (Kerr and Churchill, 2001, PMID 12933549). See microarray_set-up.pdf linked at the foot of the superSeries GSE121338 record. Zebrafish eggs were exposed to 0 (C, control) or 350 mg/L PTU (E, exposure) from 0 to 5 days post fertilization (dpf) in 6 replicates each (= 12 plates, 24 eggs per plate). At 5 dpf , 3 replicate plates of each treatment were sampled (C: control 5 dpf and E: PTU 5 dpf), resulting in 6 samples that were further analysed (exposure 5 dpf vs. control 5 dpf). The 3 remaining replicates were further raised in clean water (R: recovery) and sampled at 8 dpf (CR: recovery control 8 dpf and ER: recovery PTU 8 dpf), again resulting in 6 samples for further analyses (recovery exposure 8 dpf vs. recovery control 8 dpf; exposure 5 dpf vs. recovery exposure 8 dpf).