SIKs control osteocyte responses to parathyroid hormone

  • Nat Commun. 2016 Oct 19:7:13176. doi: 10.1038/ncomms13176.
Marc N Wein  1 ,  Yanke Liang  2 ,  Olga Goransson  3 ,  Thomas B Sundberg  4 ,  Jinhua Wang  2 ,  Elizabeth A Williams  1 ,  Maureen J O'Meara  1 ,  Nicolas Govea  1 ,  Belinda Beqo  1 ,  Shigeki Nishimori  1 ,  Kenichi Nagano  5 ,  Daniel J Brooks  1  6 ,  Janaina S Martins  1 ,  Braden Corbin  1 ,  Anthony Anselmo  7 ,  Ruslan Sadreyev  7 ,  Joy Y Wu  8 ,  Kei Sakamoto  9 ,  Marc Foretz  10 ,  Ramnik J Xavier  11  12  13 ,  Roland Baron  1  5 ,  Mary L Bouxsein  1  6 ,  Thomas J Gardella  1 ,  Paola Divieti-Pajevic  14 ,  Nathanael S Gray  2 ,  Henry M Kronenberg  1
Affiliations
  • 1. Endocrine Unit, Department of Medicine, Massachusetts General Hospital, Harvard Medical School, 50 Blossom Street, Boston, Massachusetts 02114, USA.
  • 2. Dana Farber Cancer Institute, Department of Biologic Chemistry and Molecular Pharmacology, Harvard Medical School, 450 Brookline Avenue, Boston, Massachusetts 02215, USA.
  • 3. Department of Experimental Medical Sciences, Lund University, Box 188, SE-221 00 Lund, Sweden.
  • 4. Center for the Development of Therapeutics, Broad Institute, 415 Main Street, Cambridge, Massachusetts 02142, USA.
  • 5. Harvard School of Dental Medicine, Department of Oral Medicine, Infection, and Immunity, 188 Longwood Avenue, Boston, Massachusetts 02115, US.
  • 6. Center for Advanced Orthopaedic Studies, Department of Orthopedic Surgery, Beth Israel Deaconess Medical Center, 330 Brookline Avenue, Boston, Massachusetts 02215, USA.
  • 7. Department of Molecular Biology, Massachusetts General Hospital, Harvard Medical School, 185 Cambridge Street, Boston, Massachusetts 02114, USA.
  • 8. Division of Endocrinology, Department of Medicine, Stanford University School of Medicine, 300 Pasteur Dr a175, Stanford, California 94305, USA.
  • 9. MRC Protein Phosphorylation and Ubiquitylation Unit, College of Life Sciences, University of Dundee, Dundee DD1 5EH, Scotland, UK.
  • 10. INSERM U1016, Institut Cochin, CNRS UMR8104, Universite Paris Descartes Sorbonne Pairs Cite, Paris 75013, France.
  • 11. Gastrointestinal Unit and Center for the Study of Inflammatory Bowel Disease, Department of Medicine, Massachusetts General Hospital, 55 Fruit Street, Boston, Massachusetts 02114, USA.
  • 12. Center for Computational and Integrative Biology, Massachusetts General Hospital, Harvard Medical School, 55 Fruit Street, Boston, Massachusetts 02114, USA.
  • 13. Program in Medical and Population Genetics, Broad Institute, 415 Main Street, Cambridge, Massachusetts 02142, USA.
  • 14. Henry M. Goldman School of Dental Medicine, Boston University, 100 E Newton Street, Boston, Massachusetts 02118, USA.
Abstract

Parathyroid hormone (PTH) activates receptors on osteocytes to orchestrate bone formation and resorption. Here we show that PTH inhibition of SOST (sclerostin), a Wnt antagonist, requires HDAC4 and HDAC5, whereas PTH stimulation of RANKL, a stimulator of bone resorption, requires CRTC2. Salt inducible Kinases (SIKs) control subcellular localization of HDAC4/5 and CRTC2. PTH regulates both HDAC4/5 and CRTC2 localization via phosphorylation and inhibition of SIK2. Like PTH, new small molecule SIK inhibitors cause decreased phosphorylation and increased nuclear translocation of HDAC4/5 and CRTC2. SIK inhibition mimics many of the effects of PTH in osteocytes as assessed by RNA-seq in cultured osteocytes and following in vivo administration. Once daily treatment with the small molecule SIK inhibitor YKL-05-099 increases bone formation and bone mass. Therefore, a major arm of PTH signalling in osteocytes involves SIK inhibition, and small molecule SIK inhibitors may be applied therapeutically to mimic skeletal effects of PTH.

Products