Abstract: Objective To investigate the novel mechanism by which isocitrate dehydrogenase 1(IDH1) suppresses differentiation in acute myeloid leukemia(AML) HL-60 cells. Methods Potential RNA-binding proteins were initially screened through literature review and database analyses, leading to the selection of IDH1 as the candidate of interest. RNA immunoprecipitation followed by sequencing(RIP-seq) was performed to identify RNAs bound by IDH1 in HL-60 cells. In parallel, IDH1 was knocked down via lentiviral transduction, and transcriptome profiling was conducted by RNA sequencing(RNA-seq) to assess global gene expression changes induced by IDH1 depletion. Integrated analysis of RIP-seq and RNA-seq data was further carried out to systematically characterize the expression patterns of IDH1-bound transcripts following IDH1 knockdown. Results IDH1 was found to bind a broad spectrum of RNA molecules in HL-60 cells, with mRNAs representing the predominant class. Knockdown of IDH1 resulted in marked alterations in the cellular gene expression profile. Integrated analysis revealed that IDH1-bound transcripts exhibited an overall downregulation upon IDH1 depletion and were significantly enriched in genes associated with differentiation blockade in leukemic cells. Conclusions IDH1 functions as a non-canonical RNA-binding protein that participates in the regulation of differentiation-associated genes in AML, thereby contributing to the maintenance of the undifferentiated state of leukemia cells.

Key words: isocitrate dehydrogenase 1(IDH1), acute myeloid leukemia, differentiation blockade, RNA immunoprecipitation sequencing