title: Tubulin detyrosination promotes monolayer formation and apical trafficking in epithelial cells.
abstract: The role of post-translational tubulin modifications in the development and maintenance of a polarized epithelium is not well understood. We studied the balance between detyrosinated (detyr-) and tyrosinated (tyr-) tubulin in the formation of MDCK cell monolayers. Increased quantities of detyrosinated microtubules were detected during assembly into confluent cell sheets. These tubules were composed of alternating stretches of detyr- and tyr-tubulin. Constant induction of tubulin tyrosination, which decreased the levels of detyr-tubulin by overexpression of tubulin tyrosine ligase (TTL), disrupted monolayer establishment. Detyr-tubulin-depleted cells assembled into isolated islands and developed a prematurely polarized architecture. Thus, tubulin detyrosination is required for the morphological differentiation from non-polarized cells into an epithelial monolayer. Moreover, membrane trafficking, in particular to the apical domain, was slowed down in TTL-overexpressing cells. This effect could be reversed by TTL knockdown, which suggests that detyr-tubulin-enriched microtubules serve as cytoskeletal tracks to guide membrane cargo in polarized MDCK cells.
authors.affiliation: Department of Cell Biology and Cell Pathology, Philipps-Universität Marburg, Marburg, Germany.
authors.forename: Sabrina
authors.initials: S
authors.lastname: Zink
authors.forename: Lena
authors.initials: L
authors.lastname: Grosse
authors.forename: Andrea
authors.initials: A
authors.lastname: Freikamp
authors.forename: Sebastian
authors.initials: S
authors.lastname: Bänfer
authors.forename: Frauke
authors.initials: F
authors.lastname: Müksch
authors.forename: Ralf
authors.initials: R
authors.lastname: Jacob
mesh_terms: D000818:Animals; D002454:Cell Differentiation; D002465:Cell Movement; D016764:Cell Polarity / Q000502:physiology; D002478:Cells, Cultured; D004285:Dogs; D004847:Epithelial Cells / Q000378:metabolism*; D061985:Madin Darby Canine Kidney Cells; D011499:Protein Processing, Post-Translational; D014404:Tubulin / Q000378:metabolism*; D014443:Tyrosine / Q000378:metabolism*
chemical_list: D014404:Tubulin; D014443:Tyrosine