title: An RNAi screen identifies KIF15 as a novel regulator of the endocytic trafficking of integrin.
abstract: α2β1 integrin is one of the most important collagen-binding receptors, and it has been implicated in numerous thrombotic and immune diseases. α2β1 integrin is a potent tumour suppressor, and its downregulation is associated with increased metastasis and poor prognosis in breast cancer. Currently, very little is known about the mechanism that regulates the cell-surface expression and trafficking of α2β1 integrin. Here, using a quantitative fluorescence-microscopy-based RNAi assay, we investigated the impact of 386 cytoskeleton-associated or -regulatory genes on α2 integrin endocytosis and found that 122 of these affected the intracellular accumulation of α2 integrin. Of these, 83 were found to be putative regulators of α2 integrin trafficking and/or expression, with no observed effect on the internalization of epidermal growth factor (EGF) or transferrin. Further interrogation and validation of the siRNA screen revealed a role for KIF15, a microtubule-based molecular motor, as a significant inhibitor of the endocytic trafficking of α2 integrin. Our data suggest a novel role for KIF15 in mediating plasma membrane localization of the alternative clathrin adaptor Dab2, thus impinging on pathways that regulate α2 integrin internalization.
authors.affiliation: BioQuant, University of Heidelberg, 69120 Heidelberg, Germany.
authors.forename: Anastasia
authors.initials: A
authors.lastname: Eskova
authors.affiliation: Medical Faculty, Institute for Medical Informatics and Biometry (IMB), Technische Universität Dresden, 01307 Dresden, Germany.
authors.forename: Bettina
authors.initials: B
authors.lastname: Knapp
authors.affiliation: BioQuant, University of Heidelberg, 69120 Heidelberg, Germany.
authors.forename: Dorota
authors.initials: D
authors.lastname: Matelska
authors.affiliation: BioQuant, University of Heidelberg, 69120 Heidelberg, Germany.
authors.forename: Susanne
authors.initials: S
authors.lastname: Reusing
authors.affiliation: Centre for Biotechnology, University of Turku, 20520 Turku, Finland.
authors.forename: Antti
authors.initials: A
authors.lastname: Arjonen
authors.affiliation: BioQuant, University of Heidelberg, 69120 Heidelberg, Germany.
authors.forename: Tautvydas
authors.initials: T
authors.lastname: Lisauskas
authors.affiliation: EMBL, Meyerhofstraße 1, 69117 Heidelberg, Germany.
authors.forename: Rainer
authors.initials: R
authors.lastname: Pepperkok
authors.affiliation: BioQuant, University of Heidelberg, 69120 Heidelberg, Germany.
authors.forename: Robert
authors.initials: R
authors.lastname: Russell
authors.affiliation: BioQuant, University of Heidelberg, 69120 Heidelberg, Germany Integrative Bioinformatics and Systems Biology, DKFZ, BioQuant and Institute of Pharmacy and Molecular Biotechnology, University of Heidelberg, 69120 Heidelberg, Germany.
authors.forename: Roland
authors.initials: R
authors.lastname: Eils
authors.affiliation: Centre for Biotechnology, University of Turku, 20520 Turku, Finland.
authors.forename: Johanna
authors.initials: J
authors.lastname: Ivaska
authors.affiliation: Medical Faculty, Institute for Medical Informatics and Biometry (IMB), Technische Universität Dresden, 01307 Dresden, Germany.
authors.forename: Lars
authors.initials: L
authors.lastname: Kaderali
authors.affiliation: BioQuant, University of Heidelberg, 69120 Heidelberg, Germany.
authors.forename: Holger
authors.initials: H
authors.lastname: Erfle
authors.affiliation: BioQuant, University of Heidelberg, 69120 Heidelberg, Germany vytaute.starkuviene@bioquant.uni-heidelberg.de.
authors.forename: Vytaute
authors.initials: V
authors.lastname: Starkuviene
mesh_terms: D048868:Adaptor Proteins, Signal Transducing / Q000378:metabolism*; D051017:Apoptosis Regulatory Proteins; D001943:Breast Neoplasms / Q000235:genetics*; D002462:Cell Membrane / Q000378:metabolism*; D003094:Collagen / Q000378:metabolism; D003599:Cytoskeleton / Q000235:genetics; D004705:Endocytosis / Q000235:genetics; D005260:Female; D005820:Genetic Testing / Q000379:methods; D006367:HeLa Cells; D006801:Humans; D038982:Integrin alpha2beta1 / Q000235:genetics / Q000378:metabolism*; D016547:Kinesins / Q000235:genetics / Q000378:metabolism*; D008856:Microscopy, Fluorescence; D009362:Neoplasm Metastasis; D011485:Protein Binding / Q000235:genetics; D021381:Protein Transport / Q000235:genetics; D034622:RNA Interference; D034741:RNA, Small Interfering / Q000235:genetics; D025521:Tumor Suppressor Proteins / Q000378:metabolism*
chemical_list: D048868:Adaptor Proteins, Signal Transducing; D051017:Apoptosis Regulatory Proteins; C102885:DAB2 protein, human; D038982:Integrin alpha2beta1; C486567:KIF15 protein, human; D034741:RNA, Small Interfering; D025521:Tumor Suppressor Proteins; D003094:Collagen; D016547:Kinesins
keywords: Dab2; Endocytic trafficking; Integrin; KIF15