The reciprocal species-swap test of p53 and SNI1 between Arabidopsis and human.

(A) Somatic recombination in wild type (WT) and p53-transgenic (p53) plants is shown in blue sectors by a reporter with overlapping segments of the GUS gene (1445). (B) Quantitative result of panel A. Experiments were performed in three p53-transgenic lines (n = 50 ~ 100) (S1 Table). The result of line 1 is shown. Error bars represent SEs. ***, p value < 0.001 compared to WT by binomial test. (C) Human osteosarcoma U2OS cancer cells transfected with empty vector (EV) or hemagglutinin (HA)-tagged SNI1 (SNI1). Proteins extracted from the transfected U2OS cancer cells were blotted with anti-HA antibody (abcam, ab1265). Anti-α-tubulin was used as an internal loading control. (D) The comet assay was carried out on the transfected U2OS cancer cells which were treated with 10 Gy of ionizing radiation (IR) and recovered with indicated time. The level of DNA break repair was visualized with the length of comet tail. (E) Images in panel B were analyzed using CometScore software (Tritek) to quantify the comet tail moment of at least 75 cells for each sample. Error bars represent SEs. ***, p value < 0.001, compared to EV by binomial test. Experiments were performed three times with similar results. (F) The transfected U2OS cancer cells were pulse-treated with hydroxyurea (HU) for 24 hours to introduce DNA damage and recovered in drug-free medium. (G) Quantitative results of panel D. After 14 days of culture, colonies were counted and normalized to untreated control. Error bars represent SEs. Experiments were carried out in triplicate.