Objective:To explore the role of the fat mass and obesity-associated protein (FTO) in human renal tubular epithelial cells (HK-2) suffering ischemia-reperfusion injury (IRI).Methods:The in vitro IRI mo-del was established in HK-2 cells by induction with antimycin A, A23187 and 2-deoxy-D-glucose.The cells were divided into control group and ischemia-reperfusion group (I/R group). The mRNA and protein expressions of FTO, B-cell lymphoma / leukemia 2(Bcl-2)-associated X(Bax), Bcl-2 and cleaved cysteinyl aspartate specific proteinase(cleaved Caspase-3) in HK-2 cells before and after IRI were detected by real-time fluorescent quantitative PCR(qPCR) and Western blot, respectively.Cell apoptosis was measured using flow cytometry.The level ofe N 6-methy-ladenosine (m 6A) RNA was detected by colorimetry. Results:(1) The mRNA expressions of FTO (0.15±0.05 vs.1.00±0.23) and Bcl-2 (0.14±0.07 vs.1.02±0.25) in I/R group were significantly lower than those in control group; While those of Bax (3.10±0.35 vs.1.00±0.13) and cleaved Caspase-3 (4.21±0.56 vs.1.00±0.09) were significantly higher ( t=6.28, 5.84, -9.83, and -9.84, respectively, all P<0.01). (2) The protein expressions of FTO (0.69±0.14 vs.1.37±0.02) and Bcl-2 (0.50±0.12 vs.1.25±0.21) were significantly lower in I/R group than those of control group; While those of Bax (1.04±0.08 vs.0.57±0.06) and cleaved Caspase-3 (0.99±0.05 vs.0.36±0.07) were significantly higher ( t=8.10, 5.49, -8.22, and -12.09, respectively, all P<0.05). (3) Compared with the control group, the apoptosis rate of HK-2 cells in I/R group was significantly higher [(61.70±1.01)% vs.(0.16±0.10)%, t=63.80, P<0.01]. (4) Compared with the control group, the percentage of m 6A modification level in total RNA in I/R group was significantly higher [(3.13±0.21)% vs.(1.10±0.26)%, t=-10.61, P<0.01]. Conclusions:FTO-mediated RNA m 6A modification may affect renal IRI by regulating the apoptosis of HK-2 cells.