title: Endosomes derived from clathrin-independent endocytosis serve as precursors for endothelial lumen formation.
abstract: Clathrin-independent endocytosis (CIE) is a form of bulk plasma membrane (PM) endocytosis that allows cells to sample and evaluate PM composition. Once in endosomes, the internalized proteins and lipids can be recycled back to the PM or delivered to lysosomes for degradation. Endosomes arising from CIE contain lipid and signaling molecules suggesting that they might be involved in important biological processes. During vasculogenesis, new blood vessels are formed from precursor cells in a process involving internalization and accumulation of endocytic vesicles. Here, we found that CIE has a role in endothelial lumen formation. Specifically, we found that human vascular endothelial cells (HUVECs) utilize CIE for internalization of distinct cargo molecules and that in three-dimensional cultures CIE membranes are delivered to the newly formed lumen.
authors.affiliation: Cell Biology and Physiology Center, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, Maryland, United States of America ; Intracellular Membrane Trafficking Unit, Oral and Pharyngeal Cancer Branch, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, Maryland, United States of America.
authors.forename: Natalie
authors.initials: N
authors.lastname: Porat-Shliom
authors.forename: Roberto
authors.initials: R
authors.lastname: Weigert
authors.forename: Julie G
authors.initials: JG
authors.lastname: Donaldson
mesh_terms: D002478:Cells, Cultured; D002966:Clathrin / Q000378:metabolism*; D003094:Collagen / Q000378:metabolism; D004705:Endocytosis; D011992:Endosomes / Q000378:metabolism*; D005456:Fluorescent Dyes / Q000378:metabolism; D006801:Humans; D019012:Integrin beta1 / Q000276:immunology / Q000378:metabolism; D011990:Receptors, Transferrin / Q000378:metabolism
chemical_list: D002966:Clathrin; D005456:Fluorescent Dyes; D019012:Integrin beta1; D011990:Receptors, Transferrin; D003094:Collagen