title: Elastic fiber macro-assembly is a hierarchical, cell motion-mediated process.
abstract: Elastic fibers are responsible for the extensibility and resilience of many vertebrate tissues, and improperly assembled elastic fibers are implicated in a number of human diseases. It was recently demonstrated that in vitro, cells first secrete tropoelastin into a punctate pattern of globules. To study the dynamics of macroassembly, that is, the assembly of the secreted tropoelastin globules into elastic fibers, we utilized long-term time-lapse immunofluorescence imaging and a tropoelastin p Timer fusion protein, which shifts its fluorescence spectrum over time. Pulse-chase immunolabeling of the fibroblast-like RFL-6 cells demonstrates that tropoelastin globules aggregate in a hierarchical manner, creating progressively larger fibrillar structures. By analyzing the correlation between cell and extracellular matrix movements, we show that both the aggregation process and shaping the aggregates into fibrillar form is coupled to cell motion. We also show that the motion of non-adjacent cells becomes more coordinated as the physical size of elastin-containing aggregates increases. Our data imply that the formation of elastic fibers involves the concerted action and motility of multiple cells.
authors.affiliation: Department of Anatomy and Cell Biology, University of Kansas Medical Center, Kansas City, Kansas 66160, USA.
authors.forename: Andras
authors.initials: A
authors.lastname: Czirok
authors.forename: Julia
authors.initials: J
authors.lastname: Zach
authors.forename: Beth A
authors.initials: BA
authors.lastname: Kozel
authors.forename: Robert P
authors.initials: RP
authors.lastname: Mecham
authors.forename: Elaine C
authors.initials: EC
authors.lastname: Davis
authors.forename: Brenda J
authors.initials: BJ
authors.lastname: Rongish
mesh_terms: D000818:Animals; D002417:Cattle; D002460:Cell Line; D002465:Cell Movement / Q000502:physiology*; D004547:Elastic Tissue / Q000254:growth & development / Q000378:metabolism*; D004549:Elastin / Q000378:metabolism; D005109:Extracellular Matrix / Q000378:metabolism* / Q000648:ultrastructure; D005347:Fibroblasts / Q000378:metabolism / Q000648:ultrastructure; D005455:Fluorescent Antibody Technique; D007700:Kinetics; D008164:Luminescent Proteins / Q000235:genetics / Q000378:metabolism; D008854:Microscopy, Electron; D008856:Microscopy, Fluorescence; D008954:Models, Biological; D021381:Protein Transport; D051381:Rats; D017207:Rats, Sprague-Dawley; D013997:Time Factors; D014162:Transfection; D014333:Tropoelastin / Q000235:genetics / Q000276:immunology / Q000378:metabolism
chemical_list: D008164:Luminescent Proteins; D014333:Tropoelastin; C413663:fluorescent protein 583; D004549:Elastin