Processing microRNAs for blood vessels

Abstract

Vascular Biology Patients with hereditary hemorrhagic telangiectasia (HHT) are prone to hemorrhages and nose bleeds. This is usually (but not always) because of mutant proteins in a signaling pathway that regulates blood vessel formation. Jiang et al. found that zebrafish or mice deficient in the microRNA processing enzyme Drosha had vascular defects similar to those found in HHT patients. Rare mutations in DROSHA were overrepresented in HHT patients who lacked the typical disease-associated mutations. Two of these mutants showed reduced activity and could not rescue the vascular phenotypes of Drosha-deficient zebrafish. Sci. Signal. 10 , eaan6831 (2018).