Updated project metadata. The shear stress-regulated lncRNA LASSIE interferes with endothelial cell function as knockdown of Lassie affects apoptosis, proliferation and angiogenic sprouting in vitro. RNA-antisense purification and subsequent mass spectrometry analysis identifed junctional proteins (such as PECAM-1) as interactors of LASSIE . Additional functional analyses demonstrate a role of LASSIE in shear stress sensing and barrier function in endothelial cells, by stabilizing endothelial cell junctions through connection to the cytoskeleton.