title: Essential role of cyclin-G-associated kinase (Auxilin-2) in developing and mature mice.
abstract: Hsc70 with its cochaperone, either auxilin or GAK, not only uncoats clathrin-coated vesicles but also acts as a chaperone during clathrin-mediated endocytosis. However, because synaptojanin is also involved in uncoating, it is not clear whether GAK is an essential gene. To answer this question, GAK conditional knockout mice were generated and then mated to mice expressing Cre recombinase under the control of the nestin, albumin, or keratin-14 promoters, all of which turn on during embryonic development. Deletion of GAK from brain, liver, or skin dramatically altered the histology of these tissues, causing the mice to die shortly after birth. Furthermore, by expressing a tamoxifen-inducible promoter to express Cre recombinase we showed that deletion of GAK caused lethality in adult mice. Mouse embryonic fibroblasts in which the GAK was disrupted showed a lack of clathrin-coated pits and a complete block in clathrin-mediated endocytosis. We conclude that GAK deletion blocks development and causes lethality in adult animals by disrupting clathrin-mediated endocytosis.
authors.affiliation: Laboratory of Cell Biology, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892-0301, USA.
authors.forename: Dong-Won
authors.initials: DW
authors.lastname: Lee
authors.forename: Xiaohong
authors.initials: X
authors.lastname: Zhao
authors.forename: Yang-In
authors.initials: YI
authors.lastname: Yim
authors.forename: Evan
authors.initials: E
authors.lastname: Eisenberg
authors.forename: Lois E
authors.initials: LE
authors.lastname: Greene
mesh_terms: D000818:Animals; D034021:Auxilins / Q000378:metabolism / Q000502:physiology*; D002966:Clathrin / Q000737:chemistry; D056746:Cyclin G; D056766:Cyclin G1; D016213:Cyclins / Q000737:chemistry*; D053595:Embryonic Stem Cells / Q000166:cytology; D004705:Endocytosis; D005260:Female; D017353:Gene Deletion; D018507:Gene Expression Regulation, Developmental; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D008954:Models, Biological; D017346:Protein Serine-Threonine Kinases / Q000235:genetics / Q000502:physiology*; D014018:Tissue Distribution
chemical_list: D034021:Auxilins; C534703:Ccng1 protein, mouse; D002966:Clathrin; D056746:Cyclin G; D056766:Cyclin G1; D016213:Cyclins; C534962:GAK protein, mouse; D017346:Protein Serine-Threonine Kinases