METTL3 Regulates Angiogenesis by Modulating let-7e-5p and miRNA-18a-5p Expression in Endothelial Cells

Chamorro-Jorganes, Ar�nzazu; Sweaad, Walid K.; Katare, Rajesh; Besnier, Marie; Anwar, Maryam; Beazley-Long, N.; Sala-Newby, Graciela; Ruiz-Polo, I�igo; Chandrasekera, Dhananjie; Ritchie, Alison A.; Benest, Andrew V.; Emanueli, Costanza

Abstract

Objective:
Postnatal angiogenesis is critical in vascular homeostasis and repair. m6A RNA methylation is emerging as a new layer for fine-tuning gene expression. Although the contribution of the m6A-catalyzing enzyme, METTL3 (methyltransferase-like 3), in cancer biology has been described, its role in endothelial cell (EC) function, particularly during angiogenesis, remains unclear.

Approach and Results:
To characterize the relevance of METTL3 in angiogenesis regulation, we performed gain- and loss-of-function studies in vitro. We demonstrated that depletion of METTL3 in ECs reduced the level of m6A and impaired EC function, whereas adenovirus-mediated METTL3 overexpression increased angiogenesis. Mechanistically, we showed that METTL3 depletion in ECs decreased mature angiogenic microRNAs let-7e-5p and the miR-17-92 cluster, and increased the expression of their common target, Tsp1 (thrombospondin 1). Conversely, Ad.METTL3 increased the expression of let-7e-5p and miR-17-92 cluster and reduced protein levels of Tsp1 in ECs. Moreover, overexpression of let-7e-5p and miR-18a-5p restored the angiogenic potential of METTL3-depleted ECs. We corroborated our data in vivo employing 3 mouse models. When tested in an in vivo Matrigel plug assay, METTL3-depleted ECs had diminished ability to vascularize the plug, whereas overexpression of METTL3 promoted angiogenesis. Local Ad.METTL3 gene transfer increased postischemic neovascularization in mice with either unilateral limb ischemia or myocardial infarction.

Conclusions:
METTL3 regulates m6A RNA methylation in ECs. Endogenous METTL3 is essential for EC function and angiogenesis, potentially through influencing let-7e and miR-17-92 cluster processing. Thus, the therapeutic modulation of METTL3 should be considered as a new approach for controlling angiogenic responses in the clinical setting.

Citation

Chamorro-Jorganes, A., Sweaad, W. K., Katare, R., Besnier, M., Anwar, M., Beazley-Long, N., …Emanueli, C. (2021). METTL3 Regulates Angiogenesis by Modulating let-7e-5p and miRNA-18a-5p Expression in Endothelial Cells. Arteriosclerosis, Thrombosis, and Vascular Biology, 41(6), e325-e337. https://doi.org/10.1161/atvbaha.121.316180

• Journal Article Type: Article
• Acceptance Date: May 1, 2021
• Online Publication Date: Apr 29, 2021
• Publication Date: Jun 1, 2021
• Deposit Date: May 1, 2021
• Journal: Arteriosclerosis, Thrombosis, and Vascular Biology
• Print ISSN: 1079-5642
• Electronic ISSN: 1524-4636
• Publisher: American Heart Association
• Peer Reviewed: Peer Reviewed
• Volume: 41
• Issue: 6
• Pages: e325-e337
• DOI: https://doi.org/10.1161/atvbaha.121.316180
• Keywords: Cardiology and Cardiovascular Medicine
• Public URL: https://nottingham-repository.worktribe.com/output/5504749
• Publisher URL: https://www.ahajournals.org/doi/10.1161/ATVBAHA.121.316180