title: The heterotrimeric kinesin-2 complex interacts with and regulates GLI protein function.
abstract: GLI transport to the primary cilium and nucleus is required for proper Hedgehog (HH) signaling; however, the mechanisms that mediate these trafficking events are poorly understood. Kinesin-2 motor proteins regulate ciliary transport of cargo, yet their role in GLI protein function remains unexplored. To examine a role for the heterotrimeric KIF3A-KIF3B-KAP3 kinesin-2 motor complex in regulating GLI activity, we performed a series of structure-function analyses using biochemical, cell signaling and in vivo approaches that define novel specific interactions between GLI proteins and two components of this complex, KAP3 and KIF3A. We find that all three mammalian GLI proteins interact with KAP3 and we map specific interaction sites in both proteins. Furthermore, we find that GLI proteins interact selectively with KIF3A, but not KIF3B, and that GLI interacts synergistically with KAP3 and KIF3A. Using a combination of cell signaling assays and chicken in ovo electroporation, we demonstrate that KAP3 interactions restrict GLI activator function but not GLI repressor function. These data suggest that GLI interactions with KIF3A-KIF3B-KAP3 complexes are essential for proper GLI transcriptional activity.
authors.affiliation: Department of Cell and Developmental Biology, University of Michigan, Ann Arbor, MI 48109, USA.
authors.forename: Brandon S
authors.initials: BS
authors.lastname: Carpenter
authors.affiliation: Department of Cell and Developmental Biology, University of Michigan, Ann Arbor, MI 48109, USA.
authors.forename: Renee L
authors.initials: RL
authors.lastname: Barry
authors.affiliation: Department of Cell and Developmental Biology, University of Michigan, Ann Arbor, MI 48109, USA.
authors.forename: Kristen J
authors.initials: KJ
authors.lastname: Verhey
authors.affiliation: Department of Cell and Developmental Biology, University of Michigan, Ann Arbor, MI 48109, USA benallen@umich.edu.
authors.forename: Benjamin L
authors.initials: BL
authors.lastname: Allen
mesh_terms: D048868:Adaptor Proteins, Signal Transducing / Q000235:genetics / Q000378:metabolism*; D000818:Animals; D019556:COS Cells; D002645:Chickens; D002522:Chlorocebus aethiops; D003598:Cytoskeletal Proteins / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D016547:Kinesins / Q000235:genetics / Q000378:metabolism*; D008869:Microtubule-Associated Proteins / Q000235:genetics / Q000378:metabolism*; D046912:Multiprotein Complexes / Q000235:genetics / Q000378:metabolism*; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*; D014158:Transcription, Genetic / Q000502:physiology; D000071676:Zinc Finger Protein GLI1
chemical_list: D048868:Adaptor Proteins, Signal Transducing; D003598:Cytoskeletal Proteins; C400551:GLI1 protein, human; C087415:KIF3A protein, human; C095899:KIF3B protein, human; C484407:KIFAP3 protein, human; D008869:Microtubule-Associated Proteins; D046912:Multiprotein Complexes; D014157:Transcription Factors; D000071676:Zinc Finger Protein GLI1; D016547:Kinesins
keywords: GLI; Hedgehog; KAP3; KIF3; Kinesin-2