EIF2AK2 Globally Binds and Regulates the Expression and Alternative Splicing of T2D-Related Genes in INS1 Cell

This study aimed to investigate the impact of the RNA-binding protein eukaryotic translation initiation factor 2-alpha kinase 2 (EIF2AK2) gene, also known as PKR, on the condition of islet beta cells. In this study, EIF2AK2 was overexpressed in INS1 cells, and transcriptome data following EIF2AK2 overexpression were obtained using RNA-seq technology. Additionally, potential target genes that bind to EIF2AK2 were identified through iRIP-seq technology. The proteins interacting with EIF2AK2 were characterized using co-immunoprecipitation (CO-IP) combined with mass spectrometry to elucidate the molecular regulatory mechanisms of EIF2AK2 in INS1 cells. RNA-seq results indicated that in INS1 cells overexpressing EIF2AK2, 1171 genes were differentially expressed, and 2161 alternative splicing events were significantly altered. iRIP-seq data demonstrated that reads from the immunoprecipitated samples were significantly enriched in the intronic and coding sequence (CDS) regions. EIF2AK2 preferentially binds to the GCGGCGG motif in RNA. Comprehensive analysis suggests that EIF2AK2 may directly bind to and regulate the expression of Dusp8, Btg1, and Prkce, thereby affecting pancreatic islet cell functions. Furthermore, EIF2AK2 may influence islet cell function by modulating the alternative splicing of Zfr and Pias2. Additionally, combined with Co-IP mass spectrometry data, it was discovered that EIF2AK2 can interact with 649 proteins, including various differentially expressed RNA-binding proteins, transcription factors, and histones, which may be associated with diabetes. Our results indicate that EIF2AK2 may regulate the expression or alternative splicing of mRNA related to type 2 diabetes through direct or indirect binding. Additionally, it may influence the progression of type 2 diabetes by interacting with other proteins. We propose that EIF2AK2 plays a significant role in diabetic islet beta cells, and its aberrant regulatory pattern is closely associated with the onset and progression of type 2 diabetes.