BACH1 recruits STAT3 to enhance leukemia inhibitory factor receptor activity and augments the self-renewal capacity of mouse embryonic stem cells.

BACKGROUND: Genomic studies have linked single nucleotide variants in the enhancer region of the leukemia inhibitory factor receptor (Lifr) gene to chromatin accessibility and the regulation of self-renewal in mouse embryonic stem cells (mESCs). However, the underlying mechanisms remain unclear. This study investigates the role of the transcription factor BTB and CNC homology 1 (BACH1) in regulating the Lifr enhancer and its impact on mESC pluripotency. METHODS: We performed RNA-sequencing (RNA-seq) to assess the impact of Bach1 knockout on gene expression in mESCs. Additionally, chromatin immunoprecipitation (ChIP), co-immunoprecipitation (co-IP), and luciferase reporter gene analysis were employed to investigate the mechanism by which BACH1 regulates Lifr expression. RESULTS: Genomic analyses identified BACH1 binding at the Lifr enhancer proximal to rs50454566 in mESCs. Integrated single-cell RNA sequencing (scRNA-seq) data revealed co-upregulation of Bach1 and Lifr in inner cell mass (ICM) cells. RNA-seq analyses demonstrated that Bach1 depletion attenuated Lifr expression and impeded LIFR-signal transducer and activator of transcription 3 (STAT3) signaling. Mechanistically, BACH1 recruited STAT3 to the Lifr enhancer, driving Lifr transcription and facilitating the LIFR-STAT3 signaling pathway, thereby enhancing mESC self-renewal. CONCLUSION: Our findings demonstrate that BACH1 enhances Lifr enhancer activity by recruiting STAT3 and activates the LIFR-STAT3 signaling pathway by promoting the LIFR expression, thereby maintaining mESC self-renewal. Our results complement a novel insight into the regulatory role of BACH1 in maintaining the self-renewal capacity of mESCs.