Cyclin A Degradation by Primate Cytomegalovirus Protein pUL21a Counters Its Innate Restriction of Virus Replication

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Cyclin A is critical for cellular DNA synthesis and S phase progression of the cell cycle. Human cytomegalovirus (HCMV) can reduce cyclin A levels and block cellular DNA synthesis, and cyclin A overexpression can repress HCMV replication. This interaction has only been previously observed in HCMV as murine CMV does not downregulate cyclin A, and the responsible viral factor has not been identified. We previously reported that the HCMV protein pUL21a disrupted the anaphase-promoting complex (APC), but a point mutant abrogating this activity did not phenocopy a UL21a-deficient virus, suggesting that pUL21a has an additional function. Here we identified a conserved arginine-x-leucine (RxL) cyclin-binding domain within pUL21a, which allowed pUL21a to interact with cyclin A and target it for proteasome degradation. Homologous pUL21a proteins from both chimpanzee and rhesus CMVs also contained the RxL domain and similarly degraded cyclin A, indicating that this function is conserved in primate CMVs. The RxL point mutation disabled the virus' ability to block cellular DNA synthesis and resulted in a growth defect similar to pUL21a-deficient virus. Importantly, knockdown of cyclin A rescued growth of UL21a-deficient virus. Together, these data show that during evolution, the pUL21a family proteins of primate CMVs have acquired a cyclin-binding domain that targets cyclin A for degradation, thus neutralizing its restriction on virus replication. Finally, the combined proteasome-dependent degradation of pUL21a and its cellular targets suggests that pUL21a may act as a novel suicide protein, targeting its protein cargos for destruction.

Vyšlo v časopise: Cyclin A Degradation by Primate Cytomegalovirus Protein pUL21a Counters Its Innate Restriction of Virus Replication. PLoS Pathog 9(12): e32767. doi:10.1371/journal.ppat.1003825
Kategorie: Research Article
prolekare.web.journal.doi_sk: https://doi.org/10.1371/journal.ppat.1003825

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Zdroje

1. RevelloMG, GernaG (2002) Diagnosis and management of human cytomegalovirus infection in the mother, fetus, and newborn infant. Clin Microbiol Rev 15: 680–715.

2. PomaEE, KowalikTF, ZhuL, SinclairJH, HuangES (1996) The human cytomegalovirus IE1-72 protein interacts with the cellular p107 protein and relieves p107-mediated transcriptional repression of an E2F-responsive promoter. J Virol 70: 7867–7877.

3. KamilJP, HumeAJ, JurakI, MungerK, KalejtaRF, et al. (2009) Human papillomavirus 16 E7 inactivator of retinoblastoma family proteins complements human cytomegalovirus lacking UL97 protein kinase. Proc Natl Acad Sci U S A 106: 16823–16828.

4. HagemeierC, CaswellR, HayhurstG, SinclairJ, KouzaridesT (1994) Functional interaction between the HCMV IE2 transactivator and the retinoblastoma protein. Embo J 13: 2897–2903.

5. SongYJ, StinskiMF (2002) Effect of the human cytomegalovirus IE86 protein on expression of E2F-responsive genes: a DNA microarray analysis. Proc Natl Acad Sci U S A 99: 2836–2841.

6. HumeAJ, FinkelJS, KamilJP, CoenDM, CulbertsonMR, et al. (2008) Phosphorylation of retinoblastoma protein by viral protein with cyclin-dependent kinase function. Science 320: 797–799.

7. FehrAR, GualbertoNC, SavarynJP, TerhuneSS, YuD (2012) Proteasome-dependent disruption of the E3 ubiquitin ligase anaphase-promoting complex by HCMV protein pUL21a. PLoS Pathog 8: e1002789.

8. TranK, KamilJP, CoenDM, SpectorDH (2010) Inactivation and disassembly of the anaphase-promoting complex during human cytomegalovirus infection is associated with degradation of the APC5 and APC4 subunits and does not require UL97-mediated phosphorylation of Cdh1. J Virol 84: 10832–10843.

9. QianZ, Leung-PinedaV, XuanB, Piwnica-WormsH, YuD (2010) Human cytomegalovirus protein pUL117 targets the mini-chromosome maintenance complex and suppresses cellular DNA synthesis. PLoS Pathog 6: e1000814.

10. SanchezV, McElroyAK, YenJ, TamrakarS, ClarkCL, et al. (2004) Cyclin-Dependent Kinase Activity Is Required at Early Times for Accurate Processing and Accumulation of the Human Cytomegalovirus UL122-123 and UL37 Immediate-Early Transcripts and at Later Times for Virus Production. J Virol 78: 11219–11232.

11. SanchezV, SpectorDH (2006) Cyclin-dependent kinase activity is required for efficient expression and posttranslational modification of human cytomegalovirus proteins and for production of extracellular particles. J Virol 80: 5886–5896.

12. ShlapoberskyM, SandersR, ClarkC, SpectorDH (2006) Repression of HMGA2 gene expression by human cytomegalovirus involves the IE2 86-kilodalton protein and is necessary for efficient viral replication and inhibition of cyclin A transcription. J Virol 80: 9951–9961.

13. ZydekM, HagemeierC, WiebuschL (2010) Cyclin-dependent kinase activity controls the onset of the HCMV lytic cycle. PLoS Pathog 6: e1001096.

14. OduroJD, UeckerR, HagemeierC, WiebuschL (2012) Inhibition of human cytomegalovirus immediate-early gene expression by cyclin A2-dependent kinase activity. J Virol 86: 9369–9383.

15. JaultFM, JaultJM, RuchtiF, FortunatoEA, ClarkC, et al. (1995) Cytomegalovirus infection induces high levels of cyclins, phosphorylated Rb, and p53, leading to cell cycle arrest. J Virol 69: 6697–6704.

16. SalvantBS, FortunatoEA, SpectorDH (1998) Cell cycle dysregulation by human cytomegalovirus: influence of the cell cycle phase at the time of infection and effects on cyclin transcription. J Virol 72: 3729–3741.

17. BresnahanWA, AlbrechtT, ThompsonEA (1998) The cyclin E promoter is activated by human cytomegalovirus 86-kDa immediate early protein. J Biol Chem 273: 22075–22082.

18. DuG, DuttaN, LashmitP, StinskiMF (2011) Alternative splicing of the human cytomegalovirus major immediate-early genes affects infectious-virus replication and control of cellular cyclin-dependent kinase. J Virol 85: 804–817.

19. ChenZ, KnutsonE, KuroskyA, AlbrechtT (2001) Degradation of p21cip1 in cells productively infected with human cytomegalovirus. J Virol 75: 3613–3625.

20. NorisE, ZannettiC, DemurtasA, SinclairJ, De AndreaM, et al. (2002) Cell cycle arrest by human cytomegalovirus 86-kDa IE2 protein resembles premature senescence. J Virol 76: 12135–12148.

21. FehrAR, YuD (2010) Human cytomegalovirus gene UL21a encodes a short-lived cytoplasmic protein and facilitates virus replication in fibroblasts. J Virol 84: 291–302.

22. FehrAR, YuD (2011) Human cytomegalovirus early protein pUL21a promotes efficient viral DNA synthesis and the late accumulation of immediate-early transcripts. J Virol 85: 663–674.

23. DinkelH, MichaelS, WeatherittRJ, DaveyNE, Van RoeyK, et al. (2012) ELM–the database of eukaryotic linear motifs. Nucleic Acids Res 40: D242–251.

24. AdamsPD, SellersWR, SharmaSK, WuAD, NalinCM, et al. (1996) Identification of a cyclin-cdk2 recognition motif present in substrates and p21-like cyclin-dependent kinase inhibitors. Mol Cell Biol 16: 6623–6633.

25. SchulmanBA, LindstromDL, HarlowE (1998) Substrate recruitment to cyclin-dependent kinase 2 by a multipurpose docking site on cyclin A. Proc Natl Acad Sci U S A 95: 10453–10458.

26. MachidaYJ, DuttaA (2007) The APC/C inhibitor, Emi1, is essential for prevention of rereplication. Genes Dev 21: 184–194.

27. GeleyS, KramerE, GieffersC, GannonJ, PetersJM, et al. (2001) Anaphase-promoting complex/cyclosome-dependent proteolysis of human cyclin A starts at the beginning of mitosis and is not subject to the spindle assembly checkpoint. J Cell Biol 153: 137–148.

28. SanchezV, SpectorDH (2008) Subversion of cell cycle regulatory pathways. Curr Top Microbiol Immunol 325: 243–262.

29. PetersJM (2006) The anaphase promoting complex/cyclosome: a machine designed to destroy. Nat Rev Mol Cell Biol 7: 644–656.

30. ChiY, WelckerM, HizliAA, PosakonyJJ, AebersoldR, et al. (2008) Identification of CDK2 substrates in human cell lysates. Genome Biol 9: R149.

31. EverettRD, BoutellC, McNairC, GrantL, OrrA (2010) Comparison of the biological and biochemical activities of several members of the alphaherpesvirus ICP0 family of proteins. J Virol 84: 3476–3487.

32. LiljaAE, ShenkT (2008) Efficient replication of rhesus cytomegalovirus variants in multiple rhesus and human cell types. Proc Natl Acad Sci U S A 105: 19950–19955.

33. ParedesAM, YuD (2012) Human cytomegalovirus: bacterial artificial chromosome (BAC) cloning and genetic manipulation. Curr Protoc Microbiol Chapter 14 Unit14E 14.

34. QianZ, XuanB, HongTT, YuD (2008) The full-length protein encoded by human cytomegalovirus gene UL117 is required for the proper maturation of viral replication compartments. J Virol 82: 3452–3465.