title: EB1, p150Glued, and Clasp1 control endothelial tubulogenesis through microtubule assembly, acetylation, and apical polarization.
abstract: Vascular tube morphogenesis requires the establishment of endothelial cell (EC) apical-basal polarity in three-dimensional (3D) extracellular matrices. To date, there is little understanding of how EC polarity is controlled during these highly dynamic and rapid morphogenic events. We show that the microtubule tip complex proteins, end binding 1 (EB1), p150(Glued), and Clasp1, control human EC tube formation by (1) inducing microtubule assembly and asymmetric cytoskeletal polarization, whereby acetylated and detyrosinated tubulins distribute in a subapical membrane location and filamentous actin distributes basally; (2) increasing tubulin posttranslational modifications, including required acetylation events; and (3) regulating an EC lumen signaling cascade that involves membrane type 1 matrix metallopatrinase (MT1-MMP)-dependent proteolysis as well as Pak, Raf, and Erk kinases. Another regulator of this process is the microtubule stabilizing protein, tau, which binds p150(Glued) and similarly affects EC lumen formation by controlling the levels of acetylated and detyrosinated tubulins. Increased expression of the tubulin deacetylases, sirtuin 2, and histone deacetylase 6 (HDAC6), blocks EC tube formation and cytoskeletal polarization, while siRNA suppression of these deacetylases stimulates these events. Overall, this work reveals a fundamental role for microtubule tip complex proteins in coordinating microtubule assembly, posttranslational modifications including acetylation, and apical-basal cytoskeletal polarization to control the developing apical membrane surface during blood vessel tubulogenesis in 3D matrix environments.
authors: Department of Medical Pharmacology and Physiology, University of Missouri School of Medicine and Dalton Cardiovascular Sciences Center, Columbia, MO 65212, USA.
authors: Dae Joong
authors: DJ
authors: Kim
authors: Luis A
authors: LA
authors: Martinez-Lemus
authors: George E
authors: GE
authors: Davis
mesh_terms: D000107:Acetylation; D016764:Cell Polarity; D002478:Cells, Cultured; D003599:Cytoskeleton / Q000378:metabolism; D000072159:Dynactin Complex; D005109:Extracellular Matrix / Q000378:metabolism; D061307:Human Umbilical Vein Endothelial Cells / Q000166:cytology* / Q000378:metabolism; D006801:Humans; D015151:Immunoblotting; D007124:Immunoenzyme Techniques; D008869:Microtubule-Associated Proteins / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D008870:Microtubules / Q000378:metabolism*; D009024:Morphogenesis / Q000502:physiology; D018919:Neovascularization, Physiologic; D011499:Protein Processing, Post-Translational; D034741:RNA, Small Interfering / Q000235:genetics; D014404:Tubulin / Q000378:metabolism; D014443:Tyrosine / Q000378:metabolism
chemical_list: C497850:CLASP1 protein, human; C000606360:DCTN1 protein, human; D000072159:Dynactin Complex; C500985:MAPRE1 protein, human; D008869:Microtubule-Associated Proteins; D034741:RNA, Small Interfering; D014404:Tubulin; D014443:Tyrosine