Posttranscriptional Regulation of Several Pro-atherosclerotic Genes by the RNA-binding Protein HuR is Critical for Human Atherosclerosis Progression

Background: RNA-binding protein HuR controls the fate of several genes by adding a new regulatory layer of gene expression. Here, we examined the role of HuR in endothelial pro-inflammatory responses and atherosclerosis progression in humans.

Methods: HuR silencing or overexpression, RNA stability assays, and pharmacological inhibition determined the effect of endothelial HuR in endothelial pro-inflammatory responses. HuR–mRNA interactome was characterized by HuR protein–RNA interactome assays (iCLiP-seq, RIP-seq). Expression of HuR was determined in single-cell RNA sequencing data from atherosclerotic plaques and in PBMCs derived from 977 individuals at risk for or with established atherosclerotic cardiovascular disease.

Results: Endothelial cell HuR iCLiP-seq and RIP-seq revealed several HuR binding sites in AUUUA- and UUUU(G/U)-enriched 3′UTRs of several pro-inflammatory and pro-thrombotic genes. Pharmacological inhibition or siRNA-mediated silencing of HuR reduces TNF-α cytokine-induced endothelial pro-inflammatory responses, while overexpression of HuR alone induces an EC pro-inflammatory phenotype by regulating the RNA stability of HuR targetome. Single-cell analysis revealed increased HuR expression levels in atherosclerotic plaque endothelial and immune cells. HuR mRNA expression was increased in patients with chronic coronary syndrome and was associated with the expression levels of its target mRNAs. Increased HuR at baseline was prospectively associated with accelerated progression of atherosclerosis (max. arterial wall thickness and number or size of plaques) in carotid and femoral arteries and predicted the future incidence of major adverse cardiovascular events.

Conclusion: HuR inhibition poses as a promising therapeutic target in atherosclerosis by controlling the RNA stability of several pro-atherosclerotic genes.

Publikationsverlauf

Artikel online veröffentlicht:
11. Februar 2025