WNT7B Promotes Bone Formation in part through mTORC1


WNT signaling has been implicated in both embryonic and postnatal bone formation. However, the pertinent WNT ligands and their downstream signaling mechanisms are not well understood. To investigate the osteogenic capacity of WNT7B and WNT5A, both normally expressed in the developing bone, we engineered mouse strains to express either protein in a Cre-dependent manner. Targeted induction of WNT7B, but not WNT5A, in the osteoblast lineage dramatically enhanced bone mass due to increased osteoblast number and activity; this phenotype began in the late-stage embryo and intensified postnatally. Similarly, postnatal induction of WNT7B in Runx2-lineage cells greatly stimulated bone formation. WNT7B activated mTORC1 through PI3K-AKT signaling. Genetic disruption of mTORC1 signaling by deleting Raptor in the osteoblast lineage alleviated the WNT7B-induced high-bone-mass phenotype. Thus, WNT7B promotes bone formation in part through mTORC1 activation.


Vyšlo v časopise: WNT7B Promotes Bone Formation in part through mTORC1. PLoS Genet 10(1): e32767. doi:10.1371/journal.pgen.1004145
Kategorie: Research Article
prolekare.web.journal.doi_sk: 10.1371/journal.pgen.1004145

Souhrn

WNT signaling has been implicated in both embryonic and postnatal bone formation. However, the pertinent WNT ligands and their downstream signaling mechanisms are not well understood. To investigate the osteogenic capacity of WNT7B and WNT5A, both normally expressed in the developing bone, we engineered mouse strains to express either protein in a Cre-dependent manner. Targeted induction of WNT7B, but not WNT5A, in the osteoblast lineage dramatically enhanced bone mass due to increased osteoblast number and activity; this phenotype began in the late-stage embryo and intensified postnatally. Similarly, postnatal induction of WNT7B in Runx2-lineage cells greatly stimulated bone formation. WNT7B activated mTORC1 through PI3K-AKT signaling. Genetic disruption of mTORC1 signaling by deleting Raptor in the osteoblast lineage alleviated the WNT7B-induced high-bone-mass phenotype. Thus, WNT7B promotes bone formation in part through mTORC1 activation.


Zdroje

1. CroceJC, McClayDR (2008) Evolution of the Wnt pathways. Methods in molecular biology 469: 3–18.

2. van AmerongenR, NusseR (2009) Towards an integrated view of Wnt signaling in development. Development 136: 3205–3214.

3. CleversH, NusseR (2012) Wnt/beta-Catenin Signaling and Disease. Cell 149: 1192–1205.

4. BalemansW, EbelingM, PatelN, Van HulE, OlsonP, et al. (2001) Increased bone density in sclerosteosis is due to the deficiency of a novel secreted protein (SOST). Hum Mol Genet 10: 537–543.

5. BalemansW, PatelN, EbelingM, Van HulE, WuytsW, et al. (2002) Identification of a 52 kb deletion downstream of the SOST gene in patients with van Buchem disease. J Med Genet 39: 91–97.

6. SemenovMV, HeX (2006) LRP5 mutations linked to high bone mass diseases cause reduced LRP5 binding and inhibition by SOST. The Journal of biological chemistry 281: 38276–38284.

7. BoydenLM, MaoJ, BelskyJ, MitznerL, FarhiA, et al. (2002) High bone density due to a mutation in LDL-receptor-related protein 5. N Engl J Med 346: 1513–1521.

8. AiM, HolmenSL, Van HulW, WilliamsBO, WarmanML (2005) Reduced affinity to and inhibition by DKK1 form a common mechanism by which high bone mass-associated missense mutations in LRP5 affect canonical Wnt signaling. Molecular and cellular biology 25: 4946–4955.

9. LittleRD, CarulliJP, Del MastroRG, DupuisJ, OsborneM, et al. (2002) A mutation in the LDL receptor-related protein 5 gene results in the autosomal dominant high-bone-mass trait. Am J Hum Genet 70: 11–19.

10. MajorMB, CampND, BerndtJD, YiX, GoldenbergSJ, et al. (2007) Wilms tumor suppressor WTX negatively regulates WNT/beta-catenin signaling. Science 316: 1043–1046.

11. JenkinsZA, van KogelenbergM, MorganT, JeffsA, FukuzawaR, et al. (2009) Germline mutations in WTX cause a sclerosing skeletal dysplasia but do not predispose to tumorigenesis. Nature genetics 41: 95–100.

12. KatoM, PatelMS, LevasseurR, LobovI, ChangBH, et al. (2002) Cbfa1-independent decrease in osteoblast proliferation, osteopenia, and persistent embryonic eye vascularization in mice deficient in Lrp5, a Wnt coreceptor. J Cell Biol 157: 303–314.

13. CuiY, NiziolekPJ, MacdonaldBT, ZylstraCR, AleninaN, et al. (2011) Lrp5 functions in bone to regulate bone mass. Nature medicine 17: 684–691.

14. BabijP, ZhaoW, SmallC, KharodeY, YaworskyPJ, et al. (2003) High bone mass in mice expressing a mutant LRP5 gene. Journal of bone and mineral research : the official journal of the American Society for Bone and Mineral Research 18: 960–974.

15. LiX, OminskyMS, NiuQT, SunN, DaughertyB, et al. (2008) Targeted deletion of the sclerostin gene in mice results in increased bone formation and bone strength. Journal of bone and mineral research : the official journal of the American Society for Bone and Mineral Research 23: 860–869.

16. MorvanF, BoulukosK, Clement-LacroixP, Roman RomanS, Suc-RoyerI, et al. (2006) Deletion of a single allele of the Dkk1 gene leads to an increase in bone formation and bone mass. Journal of bone and mineral research : the official journal of the American Society for Bone and Mineral Research 21: 934–945.

17. LongF (2012) Building strong bones: molecular regulation of the osteoblast lineage. Nature reviews Molecular cell biology 13: 27–38.

18. HuH, HiltonMJ, TuX, YuK, OrnitzDM, et al. (2005) Sequential roles of Hedgehog and Wnt signaling in osteoblast development. Development 132: 49–60.

19. DayTF, GuoX, Garrett-BealL, YangY (2005) Wnt/beta-catenin signaling in mesenchymal progenitors controls osteoblast and chondrocyte differentiation during vertebrate skeletogenesis. Dev Cell 8: 739–750.

20. HillTP, SpaterD, TaketoMM, BirchmeierW, HartmannC (2005) Canonical Wnt/beta-catenin signaling prevents osteoblasts from differentiating into chondrocytes. Dev Cell 8: 727–738.

21. RoddaSJ, McMahonAP (2006) Distinct roles for Hedgehog and canonical Wnt signaling in specification, differentiation and maintenance of osteoblast progenitors. Development 133: 3231–3244.

22. JoengKS, SchumacherCA, Zylstra-DiegelCR, LongF, WilliamsBO (2011) Lrp5 and Lrp6 redundantly control skeletal development in the mouse embryo. Developmental biology 359: 222–229.

23. ChenJ, LongF (2013) beta-catenin promotes bone formation and suppresses bone resorption in postnatal growing mice. Journal of bone and mineral research : the official journal of the American Society for Bone and Mineral Research 28: 1160–1169.

24. SongL, LiuM, OnoN, BringhurstFR, KronenbergHM, et al. (2012) Loss of wnt/beta-catenin signaling causes cell fate shift of preosteoblasts from osteoblasts to adipocytes. Journal of bone and mineral research : the official journal of the American Society for Bone and Mineral Research 27: 2344–2358.

25. TuX, JoengKS, NakayamaKI, NakayamaK, RajagopalJ, et al. (2007) Noncanonical Wnt Signaling through G Protein-Linked PKCdelta Activation Promotes Bone Formation. Dev Cell 12: 113–127.

26. TakadaI, MiharaM, SuzawaM, OhtakeF, KobayashiS, et al. (2007) A histone lysine methyltransferase activated by non-canonical Wnt signalling suppresses PPAR-gamma transactivation. Nat Cell Biol 9: 1273–1285.

27. InokiK, OuyangH, ZhuT, LindvallC, WangY, et al. (2006) TSC2 integrates Wnt and energy signals via a coordinated phosphorylation by AMPK and GSK3 to regulate cell growth. Cell 126: 955–968.

28. CastilhoRM, SquarizeCH, ChodoshLA, WilliamsBO, GutkindJS (2009) mTOR mediates Wnt-induced epidermal stem cell exhaustion and aging. Cell Stem Cell 5: 279–289.

29. EsenE, ChenJ, KarnerCM, OkunadeAL, PattersonBW, et al. (2013) WNT-LRP5 singaling induces Warburg effect through mTORC2 activation during osteoblast differentiation. Cell Metab In press.

30. LaplanteM, SabatiniDM (2012) mTOR signaling in growth control and disease. Cell 149: 274–293.

31. FahiminiyaS, MajewskiJ, MortJ, MoffattP, GlorieuxFH, et al. (2013) Mutations in WNT1 are a cause of osteogenesis imperfecta. Journal of medical genetics 50: 345–348.

32. KeuppK, BeleggiaF, KayseriliH, BarnesAM, SteinerM, et al. (2013) Mutations in WNT1 cause different forms of bone fragility. American journal of human genetics 92: 565–574.

33. LaineCM, JoengKS, CampeauPM, KivirantaR, TarkkonenK, et al. (2013) WNT1 mutations in early-onset osteoporosis and osteogenesis imperfecta. The New England journal of medicine 368: 1809–1816.

34. PyottSM, TranTT, LeistritzDF, PepinMG, MendelsohnNJ, et al. (2013) WNT1 mutations in families affected by moderately severe and progressive recessive osteogenesis imperfecta. American journal of human genetics 92: 590–597.

35. BennettCN, LongoKA, WrightWS, SuvaLJ, LaneTF, et al. (2005) Regulation of osteoblastogenesis and bone mass by Wnt10b. Proc Natl Acad Sci U S A 102: 3324–3329.

36. BennettCN, OuyangH, MaYL, ZengQ, GerinI, et al. (2007) Wnt10b increases postnatal bone formation by enhancing osteoblast differentiation. Journal of bone and mineral research : the official journal of the American Society for Bone and Mineral Research 22: 1924–1932.

37. StevensJR, Miranda-CarboniGA, SingerMA, BruggerSM, LyonsKM, et al. (2010) Wnt10b deficiency results in age-dependent loss of bone mass and progressive reduction of mesenchymal progenitor cells. Journal of bone and mineral research : the official journal of the American Society for Bone and Mineral Research 25: 2138–2147.

38. YangY, TopolL, LeeH, WuJ (2003) Wnt5a and Wnt5b exhibit distinct activities in coordinating chondrocyte proliferation and differentiation. Development 130: 1003–1015.

39. MaedaK, KobayashiY, UdagawaN, UeharaS, IshiharaA, et al. (2012) Wnt5a-Ror2 signaling between osteoblast-lineage cells and osteoclast precursors enhances osteoclastogenesis. Nature medicine 18: 405–412.

40. DasGuptaR, FuchsE (1999) Multiple roles for activated LEF/TCF transcription complexes during hair follicle development and differentiation. Development 126: 4557–4568.

41. ShinS, WolgamottL, YuY, BlenisJ, YoonSO (2011) Glycogen synthase kinase (GSK)-3 promotes p70 ribosomal protein S6 kinase (p70S6K) activity and cell proliferation. Proceedings of the National Academy of Sciences of the United States of America 108: E1204–1213.

42. NiziolekPJ, FarmerTL, CuiY, TurnerCH, WarmanML, et al. (2011) High-bone-mass-producing mutations in the Wnt signaling pathway result in distinct skeletal phenotypes. Bone 49: 1010–1019.

43. UrlingerS, BaronU, ThellmannM, HasanMT, BujardH, et al. (2000) Exploring the sequence space for tetracycline-dependent transcriptional activators: novel mutations yield expanded range and sensitivity. Proc Natl Acad Sci U S A 97: 7963–7968.

44. LinC, YinY, ChenH, FisherAV, ChenF, et al. (2009) Construction and characterization of a doxycycline-inducible transgenic system in Msx2 expressing cells. Genesis 47: 352–359.

45. MuyrersJP, ZhangY, TestaG, StewartAF (1999) Rapid modification of bacterial artificial chromosomes by ET-recombination. Nucleic acids research 27: 1555–1557.

46. NarayananK, WilliamsonR, ZhangY, StewartAF, IoannouPA (1999) Efficient and precise engineering of a 200 kb beta-globin human/bacterial artificial chromosome in E. coli DH10B using an inducible homologous recombination system. Gene therapy 6: 442–447.

47. JoengKS, LongF (2009) The Gli2 transcriptional activator is a crucial effector for Ihh signaling in osteoblast development and cartilage vascularization. Development 136: 4177–4185.

48. PolakP, CybulskiN, FeigeJN, AuwerxJ, RueggMA, et al. (2008) Adipose-specific knockout of raptor results in lean mice with enhanced mitochondrial respiration. Cell metabolism 8: 399–410.

49. MiaoD, HeB, JiangY, KobayashiT, SoroceanuMA, et al. (2005) Osteoblast-derived PTHrP is a potent endogenous bone anabolic agent that modifies the therapeutic efficacy of administered PTH 1–34. J Clin Invest 115: 2402–2411.

50. MuzumdarMD, TasicB, MiyamichiK, LiL, LuoL (2007) A global double-fluorescent Cre reporter mouse. Genesis 45: 593–605.

51. PerlAK, WertSE, NagyA, LobeCG, WhitsettJA (2002) Early restriction of peripheral and proximal cell lineages during formation of the lung. Proc Natl Acad Sci U S A 99: 10482–10487.

52. DanielianPS, MuccinoD, RowitchDH, MichaelSK, McMahonAP (1998) Modification of gene activity in mouse embryos in utero by a tamoxifen-inducible form of Cre recombinase. Curr Biol 8: 1323–1326.

53. HiltonMJ, TuX, CookJ, HuH, LongF (2005) Ihh controls cartilage development by antagonizing Gli3, but requires additional effectors to regulate osteoblast and vascular development. Development 132: 4339–4351.

54. BouxseinML, BoydSK, ChristiansenBA, GuldbergRE, JepsenKJ, et al. (2010) Guidelines for assessment of bone microstructure in rodents using micro-computed tomography. Journal of bone and mineral research : the official journal of the American Society for Bone and Mineral Research 25: 1468–1486.

Štítky
Genetika Reprodukčná medicína

Článok vyšiel v časopise

PLOS Genetics


2014 Číslo 1
Najčítanejšie tento týždeň
Najčítanejšie v tomto čísle
Prihlásenie
Zabudnuté heslo

Nemáte účet?  Registrujte sa

Zabudnuté heslo

Zadajte e-mailovú adresu, s ktorou ste vytvárali účet. Budú Vám na ňu zasielané informácie k nastaveniu nového hesla.

Prihlásenie

Nemáte účet?  Registrujte sa