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Stabilization of Myc through Heterotypic Poly-Ubiquitination by mLANA Is Critical for γ-Herpesvirus Lymphoproliferation


Host colonization by lymphotropic γ-herpesviruses depends critically on expansion of viral genomes in germinal center (GC) B-cells. Myc is essential for the formation and maintenance of GCs. Yet, the role of Myc in the pathogenesis of γ-herpesviruses is still largely unknown. In this study, Myc was shown to be essential for the lymphotropic γ-herpesvirus MuHV-4 biology as infected cells exhibited increased expression of Myc signature genes and the virus was unable to expand in Myc defficient GC B-cells. We describe a novel strategy of a viral protein activating Myc through increased protein stability resulting in increased progression through the cell cycle. This is acomplished by modulating a physiological post-translational regulatory pathway of Myc. The molecular mechanism involves Myc heterotypic poly-ubiquitination mediated via the viral E3 ubiquitin-ligase mLANA protein. EC5SmLANA modulates cellular control of Myc turnover by antagonizing SCFFbw7 mediated proteasomal degradation of Myc, mimicking SCFβ-TrCP. The findings here reported reveal that modulation of Myc is essential for γ-herpesvirus persistent infection, establishing a link between virus induced lymphoproliferation and disease.


Vyšlo v časopise: Stabilization of Myc through Heterotypic Poly-Ubiquitination by mLANA Is Critical for γ-Herpesvirus Lymphoproliferation. PLoS Pathog 9(8): e32767. doi:10.1371/journal.ppat.1003554
Kategorie: Research Article
prolekare.web.journal.doi_sk: https://doi.org/10.1371/journal.ppat.1003554

Souhrn

Host colonization by lymphotropic γ-herpesviruses depends critically on expansion of viral genomes in germinal center (GC) B-cells. Myc is essential for the formation and maintenance of GCs. Yet, the role of Myc in the pathogenesis of γ-herpesviruses is still largely unknown. In this study, Myc was shown to be essential for the lymphotropic γ-herpesvirus MuHV-4 biology as infected cells exhibited increased expression of Myc signature genes and the virus was unable to expand in Myc defficient GC B-cells. We describe a novel strategy of a viral protein activating Myc through increased protein stability resulting in increased progression through the cell cycle. This is acomplished by modulating a physiological post-translational regulatory pathway of Myc. The molecular mechanism involves Myc heterotypic poly-ubiquitination mediated via the viral E3 ubiquitin-ligase mLANA protein. EC5SmLANA modulates cellular control of Myc turnover by antagonizing SCFFbw7 mediated proteasomal degradation of Myc, mimicking SCFβ-TrCP. The findings here reported reveal that modulation of Myc is essential for γ-herpesvirus persistent infection, establishing a link between virus induced lymphoproliferation and disease.


Zdroje

1. LinCY, LovenJ, RahlPB, ParanalRM, BurgeCB, et al. (2012) Transcriptional Amplification in Tumor Cells with Elevated c-Myc. Cell 151: 56–67.

2. NieZ, HuG, WeiG, CuiK, YamaneA, et al. (2012) c-Myc Is a Universal Amplifier of Expressed Genes in Lymphocytes and Embryonic Stem Cells. Cell 151: 68–79.

3. DangCV (2012) MYC on the path to cancer. Cell 149: 22–35.

4. GregoryMA, HannSR (2000) c-Myc proteolysis by the ubiquitin-proteasome pathway: stabilization of c-Myc in Burkitt's lymphoma cells. Mol Cell Biol 20: 2423–2435.

5. SearsR, NuckollsF, HauraE, TayaY, TamaiK, et al. (2000) Multiple Ras-dependent phosphorylation pathways regulate Myc protein stability. Genes Dev 14: 2501–2514.

6. WelckerM, OrianA, JinJ, GrimJE, HarperJW, et al. (2004) The Fbw7 tumor suppressor regulates glycogen synthase kinase 3 phosphorylation-dependent c-Myc protein degradation. Proc Natl Acad Sci U S A 101: 9085–9090.

7. YadaM, HatakeyamaS, KamuraT, NishiyamaM, TsunematsuR, et al. (2004) Phosphorylation-dependent degradation of c-Myc is mediated by the F-box protein Fbw7. EMBO J 23: 2116–2125.

8. PopovN, SchuleinC, JaenickeLA, EilersM (2010) Ubiquitylation of the amino terminus of Myc by SCF(beta-TrCP) antagonizes SCF(Fbw7)-mediated turnover. Nat Cell Biol 12: 973–981.

9. BahramF, von der LehrN, CetinkayaC, LarssonLG (2000) c-Myc hot spot mutations in lymphomas result in inefficient ubiquitination and decreased proteasome-mediated turnover. Blood 95: 2104–2110.

10. Thorley-LawsonDA (2001) Epstein-Barr virus: exploiting the immune system. Nat Rev Immunol 1: 75–82.

11. YatesJL, WarrenN, SugdenB (1985) Stable replication of plasmids derived from Epstein-Barr virus in various mammalian cells. Nature 313: 812–815.

12. BallestasME, ChatisPA, KayeKM (1999) Efficient persistence of extrachromosomal KSHV DNA mediated by latency-associated nuclear antigen. Science 284: 641–644.

13. CaladoDP, SasakiY, GodinhoSA, PellerinA, KochertK, et al. (2012) The cell-cycle regulator c-Myc is essential for the formation and maintenance of germinal centers. Nat Immunol 13: 1092–1100.

14. Dominguez-SolaD, VictoraGD, YingCY, PhanRT, SaitoM, et al. (2012) The proto-oncogene MYC is required for selection in the germinal center and cyclic reentry. Nat Immunol 13: 1083–1091.

15. BubmanD, GuasparriI, CesarmanE (2007) Deregulation of c-Myc in primary effusion lymphoma by Kaposi's sarcoma herpesvirus latency-associated nuclear antigen. Oncogene 26: 4979–4986.

16. LiuJ, MartinHJ, LiaoG, HaywardSD (2007) The Kaposi's sarcoma-associated herpesvirus LANA protein stabilizes and activates c-Myc. J Virol 81: 10451–10459.

17. FujimuroM, LiuJ, ZhuJ, YokosawaH, HaywardSD (2005) Regulation of the interaction between glycogen synthase kinase 3 and the Kaposi's sarcoma-associated herpesvirus latency-associated nuclear antigen. J Virol 79: 10429–10441.

18. BajajBG, MurakamiM, CaiQ, VermaSC, LanK, et al. (2008) Epstein-Barr virus nuclear antigen 3C interacts with and enhances the stability of the c-Myc oncoprotein. J Virol 82: 4082–4090.

19. SimasJP, EfstathiouS (1998) Murine gammaherpesvirus 68: a model for the study of gammaherpesvirus pathogenesis. Trends Microbiol 6: 276–282.

20. CollinsCM, BossJM, SpeckSH (2009) Identification of infected B-cell populations by using a recombinant murine gammaherpesvirus 68 expressing a fluorescent protein. J Virol 83: 6484–6493.

21. de AlboranIM, O'HaganRC, GartnerF, MalynnB, DavidsonL, et al. (2001) Analysis of C-MYC function in normal cells via conditional gene-targeted mutation. Immunity 14: 45–55.

22. CasolaS, CattorettiG, UyttersprotN, KoralovSB, SeagalJ, et al. (2006) Tracking germinal center B cells expressing germ-line immunoglobulin gamma1 transcripts by conditional gene targeting. Proc Natl Acad Sci U S A 103: 7396–7401.

23. CollinsCM, SpeckSH (2012) Tracking murine gammaherpesvirus 68 infection of germinal center B cells in vivo. PLoS One 7: e33230.

24. MarquesS, EfstathiouS, SmithKG, HauryM, SimasJP (2003) Selective gene expression of latent murine gammaherpesvirus 68 in B lymphocytes. J Virol 77: 7308–7318.

25. RodriguesL, FilipeJ, SeldonMP, FonsecaL, AnratherJ, et al. (2009) Termination of NF-kappaB activity through a gammaherpesvirus protein that assembles an EC5S ubiquitin-ligase. EMBO J 28: 1283–1295.

26. HusnjakK, DikicI (2012) Ubiquitin-binding proteins: decoders of ubiquitin-mediated cellular functions. Annu Rev Biochem 81: 291–322.

27. ShafferAL3rd, StaudtLM (2012) The case of the missing c-Myc. Nat Immunol 13: 1029–1031.

28. HabisonAC, BeaucheminC, SimasJP, UsherwoodEJ, KayeKM (2012) Murine Gammaherpesvirus 68 LANA Acts on Terminal Repeat DNA To Mediate Episome Persistence. J Virol 86: 11863–11876.

29. FrescasD, PaganoM (2008) Deregulated proteolysis by the F-box proteins SKP2 and beta-TrCP: tipping the scales of cancer. Nat Rev Cancer 8: 438–449.

30. RodriguesL, Pires de MirandaM, CalocaMJ, BusteloXR, SimasJP (2006) Activation of Vav by the gammaherpesvirus M2 protein contributes to the establishment of viral latency in B lymphocytes. J Virol 80: 6123–6135.

31. PfafflMW (2001) A new mathematical model for relative quantification in real-time RT-PCR. Nucleic Acids Res 29: e45.

32. Pires de MirandaM, AlenquerM, MarquesS, RodriguesL, LopesF, et al. (2008) The Gammaherpesvirus m2 protein manipulates the Fyn/Vav pathway through a multidocking mechanism of assembly. PLoS ONE 3: e1654.

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Hygiena a epidemiológia Infekčné lekárstvo Laboratórium

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PLOS Pathogens


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