Function and Mechanism of NAT10-mediated N4-acetylcytidine modification in osteosarcoma [RIP-seq]

Despite the advance in diagnosis and treatment, the prognosis of osteosarcoma patients remains unsatisfied. Therefore, it is imperative to identify novel therapeutic targets for osteosarcoma. Through RNA sequencing (RNA-seq) combined with functional screening, N4-acetylcytidine (ac4C) acetyltransferase 10 (NAT10) was identified as a candidate therapeutic target in osteosarcoma. Upregulated NAT10 correlated with poor prognosis in osteosarcoma patients and NAT10 knockout drastically inhibited cell proliferation and metastasis in vitro and in vivo. NAT10 enhanced mRNA stability and translation efficiency of activating transcription factor 4 (ATF4) through ac4C modification. ATF4 induced transcription of asparagine synthetase (ASNS), which catalyzes asparagine (Asn) biosynthesis. Asn promote protein and nucleotide synthesis, facilitating osteosarcoma progression. Overexpression of ATF4, ASNS or supplementation of asparagine rescue the tumor inhibitory effect of NAT10 knockout. Overall design: Acetylated RNA immunoprecipitation sequencing(acRIP-Seq) was used to analysis the N4-acetylcytidine modification of mRNA in the NAT10 knockout and control osteosarcoma cells.