2. Academic Validation
  3. WNT Activates the AAK1 Kinase to Promote Clathrin-Mediated Endocytosis of LRP6 and Establish a Negative Feedback Loop

WNT Activates the AAK1 Kinase to Promote Clathrin-Mediated Endocytosis of LRP6 and Establish a Negative Feedback Loop

  • Cell Rep. 2019 Jan 2;26(1):79-93.e8. doi: 10.1016/j.celrep.2018.12.023.
Megan J Agajanian 1,  Matthew P Walker 2,  Alison D Axtman 3,  Roberta R Ruela-de-Sousa 4,  D Stephen Serafin 5,  Alex D Rabinowitz 2,  David M Graham 6,  Meagan B Ryan 1,  Tigist Tamir 1,  Yuko Nakamichi 7,  Melissa V Gammons 8,  James M Bennett 9,  Rafael M Couñago 4,  David H Drewry 3,  Jonathan M Elkins 10,  Carina Gileadi 9,  Opher Gileadi 10,  Paulo H Godoi 4,  Nirav Kapadia 3,  Susanne Müller 11,  André S Santiago 4,  Fiona J Sorrell 9,  Carrow I Wells 3,  Oleg Fedorov 9,  Timothy M Willson 3,  William J Zuercher 12,  Michael B Major 13
Affiliations

Affiliations

  • 1 Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA; Department of Pharmacology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA.
  • 2 Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA.
  • 3 Structural Genomics Consortium, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA; Division of Chemical Biology and Medicinal Chemistry, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA.
  • 4 Structural Genomics Consortium, Universidade Estadual de Campinas - UNICAMP, Campinas, SP 13083-970, Brazil.
  • 5 Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA; Department of Cell Biology and Physiology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA.
  • 6 Department of Cell Biology and Physiology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA.
  • 7 Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA; Institute for Oral Science, Matsumoto Dental University, Nagano 399-0704, Japan.
  • 8 MRC Laboratory of Molecular Biology, Cambridge Biomedical Campus, Cambridge CB2 0SL, UK.
  • 9 Structural Genomics Consortium and Target Discovery Institute, Nuffield Department of Clinical Medicine, University of Oxford, Old Road Campus Research Building, Oxford OX3 7DQ, UK.
  • 10 Structural Genomics Consortium, Universidade Estadual de Campinas - UNICAMP, Campinas, SP 13083-970, Brazil; Structural Genomics Consortium and Target Discovery Institute, Nuffield Department of Clinical Medicine, University of Oxford, Old Road Campus Research Building, Oxford OX3 7DQ, UK.
  • 11 Structural Genomics Consortium, Buchmann Institute for Molecular Life Sciences, Goethe University Frankfurt, Frankfurt am Main 60438, Germany.
  • 12 Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA; Structural Genomics Consortium, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA; Division of Chemical Biology and Medicinal Chemistry, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA.
  • 13 Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA; Department of Pharmacology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA; Department of Cell Biology and Physiology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA; Department of Computer Science, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA. Electronic address: [email protected].
PMID: 30605688 DOI: 10.1016/j.celrep.2018.12.023
Abstract

β-Catenin-dependent Wnt signal transduction governs development, tissue homeostasis, and a vast array of human diseases. Signal propagation through a WNT-Frizzled/LRP receptor complex requires proteins necessary for clathrin-mediated endocytosis (CME). Paradoxically, CME also negatively regulates Wnt signaling through internalization and degradation of the receptor complex. Here, using a gain-of-function screen of the human kinome, we report that the AP2 associated kinase 1 (AAK1), a known CME enhancer, inhibits Wnt signaling. Reciprocally, AAK1 genetic silencing or its pharmacological inhibition using a potent and selective inhibitor activates Wnt signaling. Mechanistically, we show that AAK1 promotes clearance of LRP6 from the plasma membrane to suppress the Wnt pathway. Time-course experiments support a transcription-uncoupled, WNT-driven negative feedback loop; prolonged Wnt treatment drives AAK1-dependent phosphorylation of AP2M1, clathrin-coated pit maturation, and endocytosis of LRP6. We propose that, following Wnt receptor activation, increased AAK1 function and CME limits Wnt signaling longevity.

Keywords

AAK1; AP2M1; LRP6; WNT signaling; clathrin; endocytosis; feedback loop; gain-of-function screen; kinase.

Figures
Products
  • Cat. No.
    Product Name
    Description
    Target
    Research Area
  • HY-123940
    98.93%, AAK1 Inhibitor