CK2-dependent phosphorylation of occludin regulates the interaction with ZO-proteins and tight junction integrity

Cell Communication and Signaling

Research

Sonnhild Mittag¹  Otmar Huber²  Max J Dörfel³  Julie K Westphal⁴  Susanne M Krug⁵  Michael Fromm⁵  Rudolf Tauber⁶  Christian Bellmann⁷  Jimmi Cording⁷  Ingolf E Blasig⁷ 

[1] Institute of Biochemistry II, Jena University Hospital, Friedrich-Schiller-University Jena, Nonnenplan 2, 07743, Jena, Germany;Institute of Biochemistry II, Jena University Hospital, Friedrich-Schiller-University Jena, Nonnenplan 2, 07743, Jena, Germany;Institute of Laboratory Medicine and Pathobiochemistry, Charité – Universitätsmedizin Berlin, Hindenburgdamm 30, 12200, Berlin, Germany;Institute of Biochemistry II, Jena University Hospital, Friedrich-Schiller-University Jena, Nonnenplan 2, 07743, Jena, Germany;Institute of Laboratory Medicine and Pathobiochemistry, Charité – Universitätsmedizin Berlin, Hindenburgdamm 30, 12200, Berlin, Germany;Current addresses: MJD, Cold Spring Harbor Laboratory, Stanley Institute for Cognitive Genomics, 500 Sunnyside Blvd, 11797, Woodbury, NY, USA;Institute of Biochemistry II, Jena University Hospital, Friedrich-Schiller-University Jena, Nonnenplan 2, 07743, Jena, Germany;Institute of Laboratory Medicine and Pathobiochemistry, Charité – Universitätsmedizin Berlin, Hindenburgdamm 30, 12200, Berlin, Germany;Oxacell AG, JKW, Helene-Lange-Str. 12, 14469, Potsdam, Germany;Institute of Clinical Physiology, Charité – Universitätsmedizin Berlin, Hindenburgdamm 30, 12200, Berlin, Germany;Institute of Laboratory Medicine and Pathobiochemistry, Charité – Universitätsmedizin Berlin, Hindenburgdamm 30, 12200, Berlin, Germany;Leibniz-Institute of Molecular Pharmacology, Robert-Rössle-Str. 10, 13125, Berlin, Germany;

关键词: Fluorescence Resonance Energy Transfer;    Madin Darby Canine Kidney;    Yellow Fluorescence Protein;    Madin Darby Canine Kidney Cell;    Cyan Fluorescence Protein;   

DOI  :  10.1186/1478-811X-11-40

 received in 2012-10-04, accepted in 2013-06-04,  发布年份 2013

来源: Springer

【 摘 要 】

BackgroundCasein kinase 2 (CK2) is a ubiquitously expressed Ser/Thr kinase with multiple functions in the regulation of cell proliferation and transformation. In targeting adherens and tight junctions (TJs), CK2 modulates the strength and dynamics of epithelial cell-cell contacts. Occludin previously was identified as a substrate of CK2, however the functional consequences of CK2-dependent occludin phosphorylation on TJ function were unknown.ResultsHere, we present evidence that phosphorylation of a Thr400-XXX-Thr404-XXX-Ser408 motif in the C-terminal cytoplasmic tail of human occludin regulates assembly/disassembly and barrier properties of TJs. In contrast to wildtype and T400A/T404A/S408A-mutated occludin, a phospho-mimetic Occ-T400E/T404E/S408E construct was impaired in binding to ZO-2. Interestingly, pre-phosphorylation of a GST-Occ C-terminal domain fusion protein attenuated binding to ZO-2, whereas, binding to ZO-1 was not affected. Moreover, Occ-T400E/T404E/S408E showed delayed reassembly into TJs in Ca2+-switch experiments. Stable expression of Occ-T400E/T404E/S408E in MDCK C11 cells augments barrier properties in enhancing paracellular resistance in two-path impedance spectroscopy, whereas expression of wildtype and Occ-T400A/T404A/S408A did not affect transepithelial resistance.ConclusionsThese results suggest an important role of CK2 in epithelial tight junction regulation. The occludin sequence motif at amino acids 400–408 apparently represents a hotspot for Ser/Thr-kinase phosphorylation and depending on the residue(s) which are phosphorylated it differentially modulates the functional properties of the TJ.

【 授权许可】

Unknown   
© Dörfel et al.; licensee BioMed Central Ltd. 2013. This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.