Lnc-ECAL-1 controls cerebrovascular homeostasis by targeting endothelium-specific tight junction protein Cldn5b

Cerebrovascular disorder-induced brain blood flow interruption or intracranial hemorrhage pose a great threaten to health. Emerging roles of long-noncoding RNAs (lncRNAs) in diagnosis and treatment of cardiovascular diseases have been recognized. However, whether and how lncRNAs modulate vascular homeostasis, especially network formation remain largely unknown. Here, we identified ECAL-1, a long non-coding RNA, as an important determinant for cerebrovascular homeostasis. Using the morpholino- and CRISPR /Cas9-based genetic modifications in combination with in vivo confocal imaging in zebrafish, we claimed that inactivation of ECAL-1 induced the apparent distortion of cerebral vascular pattern accompanied by intracranial hemorrhage. These cerebrovascular abnormalities were associated with decreased proliferation and anomalous interconnection of endothelial cells. Importantly, overexpression of Cldn5b, an endothelial cell-specific tight junction protein-encoding gene, could partially rescued the phenotype induced by ECAL-1 deficiency. Furthermore, bioinformatic analysis and experimental validation revealed that ECAL-1 sponged miR-23a, which targeted Cldn5b 3UTR and modulated Cldn5b expression, to maintain cerebrovascular pattern formation and integrity. Our results presented here revealed that ECAL-1 specifically controls cerebrovascular network formation and integrity through targeting miR-23a-Cldn5b axis. These findings provide a new regulation modality for cerebrovascular patterning and the potential neurovascular disorders, and ECAL-1-miR-23a axis represents as an attractive therapeutic target for cerebrovascular diseases.