RNA binding proteins potentially regulate alternative splicing of immune-related genes during the progression of coronary artery disease.

Abstract

RNA-binding proteins (RBPs) are crucial in disease as they regulate the biological functions of RNA. However, their role in coronary artery disease (CAD) progression remains unclear. RNA-seq from peripheral blood of CAD patients and no-CAD controls was analyzed to compare differentially expressed genes (DEGs) and explore their potential functions. The distribution of immune cells was assessed by CIBERSORT algorithm. Alternative splicing (AS) pattern was quantified by SUVA. Immune-related AS events (ASEs) were screened via ImmPort database. Co-expression network of ASEs, differentially expressed RBPs (DERBPs), mitochondrion and apoptosis genes, and immune cells was constructed to clarify their potential functions. A total of 1521 DEGs were detected, including 99 DERBPs, which were mainly downregulated and enriched in mRNA processing, RNA splicing, mRNA transport, and innate immune response pathways in CAD. Seven DERBPs (ANG, C4BPA, DDX60, IFIH1, IPO7, MATR3, OTUD4) were associated with immune function. Analysis of the immune cell fraction demonstrated significant increase in macrophage M0 and CD8 T cells and decrease in resting dendritic cells and activated memory CD4 T cells. Immune-related ASEs correlated with atherosclerotic stenosis were mainly the complex "alt3p/alt5p" splicing types. DERBP-AS's co-expression identified a key A5'SS event of CTSB gene. Co-expression of this event with TST and SYNCRIP may lead to a change in the proportion of macrophage M0 and CD8 T cells, respectively. The mitochondrion and apoptosis genes were also dysregulated in CAD and correlated with four DERBPs. In conclusion, RBPs have potential regulatory role in the progression of CAD by regulating the ASEs of immune-related genes and mediating immune cells composition. These findings highlight RBPs as potential therapeutic targets for CAD.