#PAGE_PARAMS# #ADS_HEAD_SCRIPTS# #MICRODATA#

A Genome-Scale RNA–Interference Screen Identifies RRAS Signaling as a Pathologic Feature of Huntington's Disease


A genome-scale RNAi screen was performed in a mammalian cell-based assay to identify modifiers of mutant huntingtin toxicity. Ontology analysis of suppressor data identified processes previously implicated in Huntington's disease, including proteolysis, glutamate excitotoxicity, and mitochondrial dysfunction. In addition to established mechanisms, the screen identified multiple components of the RRAS signaling pathway as loss-of-function suppressors of mutant huntingtin toxicity in human and mouse cell models. Loss-of-function in orthologous RRAS pathway members also suppressed motor dysfunction in a Drosophila model of Huntington's disease. Abnormal activation of RRAS and a down-stream effector, RAF1, was observed in cellular models and a mouse model of Huntington's disease. We also observe co-localization of RRAS and mutant huntingtin in cells and in mouse striatum, suggesting that activation of R-Ras may occur through protein interaction. These data indicate that mutant huntingtin exerts a pathogenic effect on this pathway that can be corrected at multiple intervention points including RRAS, FNTA/B, PIN1, and PLK1. Consistent with these results, chemical inhibition of farnesyltransferase can also suppress mutant huntingtin toxicity. These data suggest that pharmacological inhibition of RRAS signaling may confer therapeutic benefit in Huntington's disease.


Vyšlo v časopise: A Genome-Scale RNA–Interference Screen Identifies RRAS Signaling as a Pathologic Feature of Huntington's Disease. PLoS Genet 8(11): e32767. doi:10.1371/journal.pgen.1003042
Kategorie: Research Article
prolekare.web.journal.doi_sk: https://doi.org/10.1371/journal.pgen.1003042

Souhrn

A genome-scale RNAi screen was performed in a mammalian cell-based assay to identify modifiers of mutant huntingtin toxicity. Ontology analysis of suppressor data identified processes previously implicated in Huntington's disease, including proteolysis, glutamate excitotoxicity, and mitochondrial dysfunction. In addition to established mechanisms, the screen identified multiple components of the RRAS signaling pathway as loss-of-function suppressors of mutant huntingtin toxicity in human and mouse cell models. Loss-of-function in orthologous RRAS pathway members also suppressed motor dysfunction in a Drosophila model of Huntington's disease. Abnormal activation of RRAS and a down-stream effector, RAF1, was observed in cellular models and a mouse model of Huntington's disease. We also observe co-localization of RRAS and mutant huntingtin in cells and in mouse striatum, suggesting that activation of R-Ras may occur through protein interaction. These data indicate that mutant huntingtin exerts a pathogenic effect on this pathway that can be corrected at multiple intervention points including RRAS, FNTA/B, PIN1, and PLK1. Consistent with these results, chemical inhibition of farnesyltransferase can also suppress mutant huntingtin toxicity. These data suggest that pharmacological inhibition of RRAS signaling may confer therapeutic benefit in Huntington's disease.


Zdroje

1. The Huntington's Disease Collaborative Research Group, Cell 72, 971 (Mar 26, 1993).

2. de la MonteSM, VonsattelJP, RichardsonEPJr (1988) Morphometric demonstration of atrophic changes in the cerebral cortex, white matter, and neostriatum in Huntington's disease. J Neuropathol Exp Neurol 47: 516–525.

3. ZuccatoC, CiammolaA, RigamontiD, LeavittBR, GoffredoD, et al. (2001) Loss of huntingtin-mediated BDNF gene transcription in Huntington's disease. Science 293: 493–498.

4. ChaCI, ChungYH, ShinCM, ShinDH, KimYS, et al. (2000) Immunocytochemical study on the distribution of nitrotyrosine in the brain of the transgenic mice expressing a human Cu/Zn SOD mutation. Brain Res 853: 156–161.

5. WeydtP, PinedaVV, TorrenceAE, LibbyRT, SatterfieldTF, et al. (2006) Thermoregulatory and metabolic defects in Huntington's disease transgenic mice implicate PGC-1alpha in Huntington's disease neurodegeneration. Cell Metab 4: 349–362.

6. BenceNF, SampatRM, KopitoRR (2001) Impairment of the ubiquitin-proteasome system by protein aggregation. Science 292: 1552–1555.

7. BrassAL, DykxhoornDM, BenitaY, YanN, EngelmanA, et al. (2008) Identification of host proteins required for HIV infection through a functional genomic screen. Science 319: 921–926.

8. SchlabachMR, LuoJ, SoliminiNL, HuG, XuQ, et al. (2008) Cancer proliferation gene discovery through functional genomics. Science 319: 620–624.

9. TrettelF, RigamontiD, Hilditch-MaguireP, WheelerVC, SharpAH, et al. (2000) Dominant phenotypes produced by the HD mutation in STHdh(Q111) striatal cells. Hum Mol Genet 9: 2799–2809.

10. Al-RamahiI, PerezAM, LimJ, ZhangM, SorensenR, et al. (2007) dAtaxin-2 mediates expanded Ataxin-1-induced neurodegeneration in a Drosophila model of SCA1. PLoS Genet 3: e234 doi:10.1371/journal.pgen.0030234.

11. BauerS, GrossmannS, VingronM, RobinsonPN (2008) Ontologizer 2.0–a multifunctional tool for GO term enrichment analysis and data exploration. Bioinformatics 24: 1650–1651.

12. WellingtonCL, EllerbyLM, GutekunstCA, RogersD, WarbyS, et al. (2002) Caspase cleavage of mutant huntingtin precedes neurodegeneration in Huntington's disease. J Neurosci 22: 7862–7872.

13. GafniJ, HermelE, YoungJE, WellingtonCL, HaydenMR, et al. (2004) Inhibition of calpain cleavage of huntingtin reduces toxicity: accumulation of calpain/caspase fragments in the nucleus. J Biol Chem 279: 20211–20220.

14. GoldbergYP, NicholsonDW, RasperDM, KalchmanMA, KoideHB, et al. (1996) Cleavage of huntingtin by apopain, a proapoptotic cysteine protease, is modulated by the polyglutamine tract. Nat Genet 13: 442–449.

15. YoungAB, GreenamyreJT, HollingsworthZ, AlbinR, D'AmatoC, et al. (1988) NMDA receptor losses in putamen from patients with Huntington's disease. Science 241: 981–983.

16. GuidettiP, Luthi-CarterRE, AugoodSJ, SchwarczR (2004) Neostriatal and cortical quinolinate levels are increased in early grade Huntington's disease. Neurobiol Dis 17: 455–461.

17. GuidettiP, BatesGP, GrahamRK, HaydenMR, LeavittBR, et al. (2006) Elevated brain 3-hydroxykynurenine and quinolinate levels in Huntington disease mice. Neurobiol Dis 23: 190–197.

18. LevineMS, KlapsteinGJ, KoppelA, GruenE, CepedaC, et al. (1999) Enhanced sensitivity to N-methyl-D-aspartate receptor activation in transgenic and knockin mouse models of Huntington's disease. J Neurosci Res 58: 515–532.

19. LeavittBR, van RaamsdonkJM, ShehadehJ, FernandesH, MurphyZ, et al. (2006) Wild-type huntingtin protects neurons from excitotoxicity. J Neurochem 96: 1121–1129.

20. KhoshnanA, KoJ, WatkinEE, PaigeLA, ReinhartPH, et al. (2004) Activation of the IkappaB kinase complex and nuclear factor-kappaB contributes to mutant huntingtin neurotoxicity. J Neurosci 24: 7999–8008.

21. ThompsonLM, AikenCT, KaltenbachLS, AgrawalN, IllesK, et al. (2009) IKK phosphorylates Huntingtin and targets it for degradation by the proteasome and lysosome. J Cell Biol 187: 1083–1099.

22. KhoshnanA, KoJ, TescuS, BrundinP, PattersonPH (2009) IKKalpha and IKKbeta regulation of DNA damage-induced cleavage of huntingtin. PLoS ONE 4: e5768 doi:10.1371/journal.pone.0005768.

23. BjorkqvistM, WildEJ, ThieleJ, SilvestroniA, AndreR, et al. (2008) A novel pathogenic pathway of immune activation detectable before clinical onset in Huntington's disease. J Exp Med 205: 1869–1877.

24. ChaJH (2000) Transcriptional dysregulation in Huntington's disease. Trends Neurosci 23: 387–392.

25. SteffanJS, KazantsevA, Spasic-BoskovicO, GreenwaldM, ZhuYZ, et al. (2000) The Huntington's disease protein interacts with p53 and CREB-binding protein and represses transcription. Proc Natl Acad Sci U S A 97: 6763–6768.

26. BaeBI, XuH, IgarashiS, FujimuroM, AgrawalN, et al. (2005) p53 mediates cellular dysfunction and behavioral abnormalities in Huntington's disease. Neuron 47: 29–41.

27. LiSH, ChengAL, ZhouH, LamS, RaoM, et al. (2002) Interaction of Huntington disease protein with transcriptional activator Sp1. Mol Cell Biol 22: 1277–1287.

28. ZhaiW, JeongH, CuiL, KraincD, TjianR (2005) In vitro analysis of huntingtin-mediated transcriptional repression reveals multiple transcription factor targets. Cell 123: 1241–1253.

29. LoweDG, CaponDJ, DelwartE, SakaguchiAY, NaylorSL, et al. (1987) Structure of the human and murine R-ras genes, novel genes closely related to ras proto-oncogenes. Cell 48: 137–146.

30. ZhangZ, VuoriK, WangH, ReedJC, RuoslahtiE (1996) Integrin activation by R-ras. Cell 85: 61–69.

31. WangHG, MillanJA, CoxAD, DerCJ, RappUR, et al. (1995) R-Ras promotes apoptosis caused by growth factor deprivation via a Bcl-2 suppressible mechanism. J Cell Biol 129: 1103–1114.

32. IvinsJK, YurchencoPD, LanderAD (2000) Regulation of neurite outgrowth by integrin activation. J Neurosci 20: 6551–6560.

33. OinumaI, IshikawaY, KatohH, NegishiM (2004) The Semaphorin 4D receptor Plexin-B1 is a GTPase activating protein for R-Ras. Science 305: 862–865.

34. MasonCS, SpringerCJ, CooperRG, Superti-FurgaG, MarshallCJ, et al. (1999) Serine and tyrosine phosphorylations cooperate in Raf-1, but not B-Raf activation. Embo J 18: 2137–2148.

35. DoughertyMK, MullerJ, RittDA, ZhouM, ZhouXZ, et al. (2005) Regulation of Raf-1 by direct feedback phosphorylation. Mol Cell 17: 215–224.

36. EckerdtF, YuanJ, SaxenaK, MartinB, KappelS, et al. (2005) Polo-like kinase 1-mediated phosphorylation stabilizes Pin1 by inhibiting its ubiquitination in human cells. J Biol Chem 280: 36575–36583.

37. XuZ, WilliamsBR (2000) The B56alpha regulatory subunit of protein phosphatase 2A is a target for regulation by double-stranded RNA-dependent protein kinase PKR. Mol Cell Biol 20: 5285–5299.

38. PeelAL, RaoRV, CottrellBA, HaydenMR, EllerbyLM, et al. (2001) Double-stranded RNA-dependent protein kinase, PKR, binds preferentially to Huntington's disease (HD) transcripts and is activated in HD tissue. Hum Mol Genet 10: 1531–1538.

39. UeharaN, MatsuokaY, TsuburaA (2008) Mesothelin promotes anchorage-independent growth and prevents anoikis via extracellular signal-regulated kinase signaling pathway in human breast cancer cells. Mol Cancer Res 6: 186–193.

40. KongPJ, KilMO, LeeH, KimSS, JohnsonGV, et al. (2009) Increased expression of Bim contributes to the potentiation of serum deprivation-induced apoptotic cell death in Huntington's disease knock-in striatal cell line. Neurol Res 31: 77–83.

41. ZangM, HayneC, LuoZ (2002) Interaction between active Pak1 and Raf-1 is necessary for phosphorylation and activation of Raf-1. J Biol Chem 277: 4395–4405.

42. SpaargarenM, MartinGA, McCormickF, Fernandez-SarabiaMJ, BischoffJR (1994) The Ras-related protein R-ras interacts directly with Raf-1 in a GTP-dependent manner. Biochem J 300(Pt 2): 303–307.

43. ChenZ, GibsonTB, RobinsonF, SilvestroL, PearsonG, et al. (2001) MAP kinases. Chem Rev 101: 2449–2476.

44. WangHG, RappUR, ReedJC (1996) Bcl-2 targets the protein kinase Raf-1 to mitochondria. Cell 87: 629–638.

45. ApostolBL, IllesK, PallosJ, BodaiL, WuJ, et al. (2006) Mutant huntingtin alters MAPK signaling pathways in PC12 and striatal cells: ERK1/2 protects against mutant huntingtin-associated toxicity. Hum Mol Genet 15: 273–285.

46. MeiM, SuB, HarrisonK, ChaoM, SiedlakSL, et al. (2006) Distribution, levels and phosphorylation of Raf-1 in Alzheimer's disease. J Neurochem 99: 1377–1388.

47. EcheverriaV, BurgessS, Gamble-GeorgeJ, ArendashGW, CitronBA (2008) Raf inhibition protects cortical cells against beta-amyloid toxicity. Neurosci Lett 444: 92–96.

48. HuserM, LuckettJ, ChiloechesA, MercerK, IwobiM, et al. (2001) MEK kinase activity is not necessary for Raf-1 function. Embo J 20: 1940–1951.

49. ChenJ, FujiiK, ZhangL, RobertsT, FuH (2001) Raf-1 promotes cell survival by antagonizing apoptosis signal-regulating kinase 1 through a MEK-ERK independent mechanism. Proc Natl Acad Sci U S A 98: 7783–7788.

50. O'NeillE, RushworthL, BaccariniM, KolchW (2004) Role of the kinase MST2 in suppression of apoptosis by the proto-oncogene product Raf-1. Science 306: 2267–2270.

51. PiazzollaD, MeisslK, KucerovaL, RubioloC, BaccariniM (2005) Raf-1 sets the threshold of Fas sensitivity by modulating Rok-alpha signaling. J Cell Biol 171: 1013–1022.

52. MangiariniL, SathasivamK, SellerM, CozensB, HarperA, et al. (1996) Exon 1 of the HD gene with an expanded CAG repeat is sufficient to cause a progressive neurological phenotype in transgenic mice. Cell 87: 493–506.

53. MenalledLB, SisonJD, DragatsisI, ZeitlinS, ChesseletMF (2003) Time course of early motor and neuropathological anomalies in a knock-in mouse model of Huntington's disease with 140 CAG repeats. J Comp Neurol 465: 11–26.

54. HerrmannC, MartinGA, WittinghoferA (1995) Quantitative analysis of the complex between p21ras and the Ras-binding domain of the human Raf-1 protein kinase. J Biol Chem 270: 2901–2905.

55. TaylorSJ, ShallowayD (1996) Cell cycle-dependent activation of Ras. Curr Biol 6: 1621–1627.

56. PoulikakosPI, ZhangC, BollagG, ShokatKM, RosenN RAF inhibitors transactivate RAF dimers and ERK signalling in cells with wild-type BRAF. Nature 464: 427–430.

57. SubramaniamS, SixtKM, BarrowR, SnyderSH (2009) Rhes, a striatal specific protein, mediates mutant-huntingtin cytotoxicity. Science 324: 1327–1330.

58. LiuZ, MerayRK, GrammatopoulosTN, FredenburgRA, CooksonMR, et al. (2009) Membrane-associated farnesylated UCH-L1 promotes alpha-synuclein neurotoxicity and is a therapeutic target for Parkinson's disease. Proc Natl Acad Sci U S A 106: 4635–4640.

59. FongLG, FrostD, MetaM, QiaoX, YangSH, et al. (2006) A protein farnesyltransferase inhibitor ameliorates disease in a mouse model of progeria. Science 311: 1621–1623.

60. ChinPC, LiuL, MorrisonBE, SiddiqA, RatanRR, et al. (2004) The c-Raf inhibitor GW5074 provides neuroprotection in vitro and in an animal model of neurodegeneration through a MEK-ERK and Akt-independent mechanism. J Neurochem 90: 595–608.

61. UesugiK, OinumaI, KatohH, NegishiM (2009) Different requirement for Rnd GTPases of R-Ras GAP activity of Plexin-C1 and Plexin-D1. J Biol Chem 284: 6743–6751.

62. ConklinMW, Ada-NguemaA, ParsonsM, RichingKM, KeelyPJ R-Ras regulates beta1-integrin trafficking via effects on membrane ruffling and endocytosis. BMC Cell Biol 11: 14.

63. LiX, ValenciaA, SappE, MassoN, AlexanderJ, et al. Aberrant Rab11-dependent trafficking of the neuronal glutamate transporter EAAC1 causes oxidative stress and cell death in Huntington's disease. J Neurosci 30: 4552–4561.

64. TanakaY, IgarashiS, NakamuraM, GafniJ, TorcassiC, et al. (2006) Progressive phenotype and nuclear accumulation of an amino-terminal cleavage fragment in a transgenic mouse model with inducible expression of full-length mutant huntingtin. Neurobiol Dis 21: 381–391.

65. WankerEE, ScherzingerE, HeiserV, SittlerA, EickhoffH, et al. (1999) Membrane filter assay for detection of amyloid-like polyglutamine-containing protein aggregates. Methods Enzymol 309: 375–386.

Štítky
Genetika Reprodukčná medicína

Článok vyšiel v časopise

PLOS Genetics


2012 Číslo 11
Najčítanejšie tento týždeň
Najčítanejšie v tomto čísle
Kurzy

Zvýšte si kvalifikáciu online z pohodlia domova

Získaná hemofilie - Povědomí o nemoci a její diagnostika
nový kurz

Eozinofilní granulomatóza s polyangiitidou
Autori: doc. MUDr. Martina Doubková, Ph.D.

Všetky kurzy
Prihlásenie
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

#ADS_BOTTOM_SCRIPTS#