gas2l1 knockout or the disruption of GAS2L1 Ser352 phosphorylation does not affect centrosome maturation. (A and B) RPE-1 parental cells and sublines were stained for (A) γ-tubulin or (B) pericentrin. DNA was labeled with Hoechst 33258. Prophase cells were identified based on DNA patterns and analyzed for centrosomal intensities of γ-tubulin and pericentrin; data were collected from three independent experiments. Arrowheads: centrosomes. γ-Tubulin: n = 52 (Parental), 58 (gas2l1 KO), 61 (gas2l1 KO + WT), 55 (gas2l1 KO + S352A), and 50 (gas2l1 KO + S352D). Pericentrin: n = 48 (Parental), 51 (gas2l1 KO), 44 (gas2l1 KO + WT), 49 (gas2l1 KO + S352A), and 56 (gas2l1 KO + S352D). (C) Microtubule regrowth assay was performed on RPE-1 parental cells and sublines. Microtubules were visualized through anti-α-tubulin labeling, and DNA was stained with Hoechst 33258. Centrosome-based microtubule asters were quantified in prophase cells from three independent experiments: n = 50 (Parental), 50 (gas2l1 KO), 51 (gas2l1 KO + WT), 55 (gas2l1 KO + S352A), and 53 (gas2l1 KO + S352D). Boxed regions are enlarged to show microtubule asters. Scale bars, 10 µm.