title: Ankyrin-B is a PI3P effector that promotes polarized α5β1-integrin recycling via recruiting RabGAP1L to early endosomes.
abstract: Endosomal membrane trafficking requires coordination between phosphoinositide lipids, Rab GTPases, and microtubule-based motors to dynamically determine endosome identity and promote long-range organelle transport. Here we report that ankyrin-B (AnkB), through integrating all three systems, functions as a critical node in the protein circuitry underlying polarized recycling of α5β1-integrin in mouse embryonic fibroblasts, which enables persistent fibroblast migration along fibronectin gradients. AnkB associates with phosphatidylinositol 3-phosphate (PI3P)-positive organelles in fibroblasts and binds dynactin to promote their long-range motility. We demonstrate that AnkB binds to Rab GTPase Activating Protein 1-Like (RabGAP1L) and recruits it to PI3P-positive organelles, where RabGAP1L inactivates Rab22A, and promotes polarized trafficking to the leading edge of migrating fibroblasts. We further determine that α5β1-integrin depends on an AnkB/RabGAP1L complex for polarized recycling. Our results reveal AnkB as an unexpected key element in coordinating polarized transport of α5β1-integrin and likely of other specialized endocytic cargos.
authors.affiliation: Department of Biochemistry, Duke University Medical Center, Durham, United States.|Department of Cell Biology, Duke University Medical Center, Durham, United States.|Department of Neurobiology, Duke University Medical Center, Durham, United States.|Howard Hughes Medical Institute, Duke University Medical Center, Durham, United States.
authors.forename: Fangfei
authors.initials: F
authors.lastname: Qu
authors.affiliation: Department of Biochemistry, Duke University Medical Center, Durham, United States.|Department of Cell Biology, Duke University Medical Center, Durham, United States.|Department of Neurobiology, Duke University Medical Center, Durham, United States.|Howard Hughes Medical Institute, Duke University Medical Center, Durham, United States.
authors.forename: Damaris N
authors.initials: DN
authors.lastname: Lorenzo
authors.affiliation: UNC Lineberger Comprehensive Cancer Center, The University of North Carolina at Chapel Hill, Durham, United States.|Department of Cell Biology and Physiology, The University of North Carolina at Chapel Hill, Chapel Hill, United States.
authors.forename: Samantha J
authors.initials: SJ
authors.lastname: King
authors.affiliation: UNC Lineberger Comprehensive Cancer Center, The University of North Carolina at Chapel Hill, Durham, United States.|Department of Cell Biology and Physiology, The University of North Carolina at Chapel Hill, Chapel Hill, United States.
authors.forename: Rebecca
authors.initials: R
authors.lastname: Brooks
authors.affiliation: UNC Lineberger Comprehensive Cancer Center, The University of North Carolina at Chapel Hill, Durham, United States.|Department of Cell Biology and Physiology, The University of North Carolina at Chapel Hill, Chapel Hill, United States.
authors.forename: James E
authors.initials: JE
authors.lastname: Bear
authors.affiliation: Department of Biochemistry, Duke University Medical Center, Durham, United States.|Department of Cell Biology, Duke University Medical Center, Durham, United States.|Department of Neurobiology, Duke University Medical Center, Durham, United States.|Howard Hughes Medical Institute, Duke University Medical Center, Durham, United States.
authors.forename: Vann
authors.identifier: 0000-0003-2695-7209
authors.initials: V
authors.lastname: Bennett
mesh_terms: D000818:Animals; D017487:Ankyrins / Q000235:genetics / Q000378:metabolism*; D000072159:Dynactin Complex / Q000235:genetics / Q000378:metabolism*; D011992:Endosomes / Q000235:genetics / Q000378:metabolism; D005347:Fibroblasts / Q000378:metabolism; D020690:GTPase-Activating Proteins / Q000235:genetics / Q000378:metabolism*; D006649:Histocompatibility Antigens; D006801:Humans; D039081:Integrin alpha5beta1 / Q000235:genetics / Q000378:metabolism*; D008055:Lipids / Q000235:genetics; D026901:Membrane Transport Proteins / Q000235:genetics / Q000378:metabolism; D051379:Mice; D018129:Phosphatidylinositol Phosphates / Q000378:metabolism; D011485:Protein Binding
chemical_list: C498995:Ank2 protein, mouse; D017487:Ankyrins; D000072159:Dynactin Complex; D020690:GTPase-Activating Proteins; C056907:Hh1 protein, mouse; D006649:Histocompatibility Antigens; D039081:Integrin alpha5beta1; D008055:Lipids; D026901:Membrane Transport Proteins; D018129:Phosphatidylinositol Phosphates; C055525:phosphatidylinositol 3-phosphate
keywords: Ankyrin-B; Endosomal transport; RabGAP1L; biochemistry; cell biology; haptotaxis; mouse; α5β1-integrin