#PAGE_PARAMS# #ADS_HEAD_SCRIPTS# #MICRODATA#

The Canine Papillomavirus and Gamma HPV E7 Proteins Use an Alternative Domain to Bind and Destabilize the Retinoblastoma Protein


The high-risk HPV E6 and E7 proteins cooperate to immortalize primary human cervical cells and the E7 protein can independently transform fibroblasts in vitro, primarily due to its ability to associate with and degrade the retinoblastoma tumor suppressor protein, pRb. The binding of E7 to pRb is mediated by a conserved Leu-X-Cys-X-Glu (LXCXE) motif in the conserved region 2 (CR2) of E7 and this domain is both necessary and sufficient for E7/pRb association. In the current study, we report that the E7 protein of the malignancy-associated canine papillomavirus type 2 encodes an E7 protein that has serine substituted for cysteine in the LXCXE motif. In HPV, this substitution in E7 abrogates pRb binding and degradation. However, despite variation at this critical site, the canine papillomavirus E7 protein still bound and degraded pRb. Even complete deletion of the LXSXE domain of canine E7 failed to interfere with binding to pRb in vitro and in vivo. Rather, the dominant binding site for pRb mapped to the C-terminal domain of canine E7. Finally, while the CR1 and CR2 domains of HPV E7 are sufficient for degradation of pRb, the C-terminal region of canine E7 was also required for pRb degradation. Screening of HPV genome sequences revealed that the LXSXE motif of the canine E7 protein was also present in the gamma HPVs and we demonstrate that the gamma HPV-4 E7 protein also binds pRb in a similar way. It appears, therefore, that the type 2 canine PV and gamma-type HPVs not only share similar properties with respect to tissue specificity and association with immunosuppression, but also the mechanism by which their E7 proteins interact with pRb.


Vyšlo v časopise: The Canine Papillomavirus and Gamma HPV E7 Proteins Use an Alternative Domain to Bind and Destabilize the Retinoblastoma Protein. PLoS Pathog 6(9): e32767. doi:10.1371/journal.ppat.1001089
Kategorie: Research Article
prolekare.web.journal.doi_sk: https://doi.org/10.1371/journal.ppat.1001089

Souhrn

The high-risk HPV E6 and E7 proteins cooperate to immortalize primary human cervical cells and the E7 protein can independently transform fibroblasts in vitro, primarily due to its ability to associate with and degrade the retinoblastoma tumor suppressor protein, pRb. The binding of E7 to pRb is mediated by a conserved Leu-X-Cys-X-Glu (LXCXE) motif in the conserved region 2 (CR2) of E7 and this domain is both necessary and sufficient for E7/pRb association. In the current study, we report that the E7 protein of the malignancy-associated canine papillomavirus type 2 encodes an E7 protein that has serine substituted for cysteine in the LXCXE motif. In HPV, this substitution in E7 abrogates pRb binding and degradation. However, despite variation at this critical site, the canine papillomavirus E7 protein still bound and degraded pRb. Even complete deletion of the LXSXE domain of canine E7 failed to interfere with binding to pRb in vitro and in vivo. Rather, the dominant binding site for pRb mapped to the C-terminal domain of canine E7. Finally, while the CR1 and CR2 domains of HPV E7 are sufficient for degradation of pRb, the C-terminal region of canine E7 was also required for pRb degradation. Screening of HPV genome sequences revealed that the LXSXE motif of the canine E7 protein was also present in the gamma HPVs and we demonstrate that the gamma HPV-4 E7 protein also binds pRb in a similar way. It appears, therefore, that the type 2 canine PV and gamma-type HPVs not only share similar properties with respect to tissue specificity and association with immunosuppression, but also the mechanism by which their E7 proteins interact with pRb.


Zdroje

1. zur HausenH

2002 Papillomaviruses and cancer: from basic studies to clinical application. Nat Rev Cancer 2 342 350

2. StarkA

GregoireL

PilarskiR

ZarboA

GabaA

2008 Human papillomavirus, cervical cancer and women's knowledge. Cancer Detect Prev

3. WoodmanCB

CollinsSI

YoungLS

2007 The natural history of cervical HPV infection: unresolved issues. Nat Rev Cancer 7 11 22

4. McLaughlin-DrubinME

MungerK

2009 The human papillomavirus E7 oncoprotein. Virology 384 335 344

5. HowieHL

KatzenellenbogenRA

GallowayDA

2009 Papillomavirus E6 proteins. Virology 384 324 334

6. HuhK

ZhouX

HayakawaH

ChoJY

LibermannTA

2007 Human papillomavirus type 16 E7 oncoprotein associates with the cullin 2 ubiquitin ligase complex, which contributes to degradation of the retinoblastoma tumor suppressor. J Virol 81 9737 9747

7. BouletG

HorvathC

Vanden BroeckD

SahebaliS

BogersJ

2007 Human papillomavirus: E6 and E7 oncogenes. Int J Biochem Cell Biol 39 2006 2011

8. FiggeJ

WebsterT

SmithTF

PauchaE

1988 Prediction of similar transforming regions in simian virus 40 large T, adenovirus E1A, and myc oncoproteins. J Virol 62 1814 1818

9. EdmondsC

VousdenKH

1989 A point mutational analysis of human papillomavirus type 16 E7 protein. J Virol 63 2650 2656

10. PhelpsWC

MungerK

YeeCL

BarnesJA

HowleyPM

1992 Structure-function analysis of the human papillomavirus type 16 E7 oncoprotein. J Virol 66 2418 2427

11. JewersRJ

HildebrandtP

LudlowJW

KellB

McCanceDJ

1992 Regions of human papillomavirus type 16 E7 oncoprotein required for immortalization of human keratinocytes. J Virol 66 1329 1335

12. StoreyA

AlmondN

OsbornK

CrawfordL

1990 Mutations of the human papillomavirus type 16 E7 gene that affect transformation, transactivation and phosphorylation by the E7 protein. J Gen Virol 71 (Pt 4) 965 970

13. MungerK

WernessBA

DysonN

PhelpsWC

HarlowE

1989 Complex formation of human papillomavirus E7 proteins with the retinoblastoma tumor suppressor gene product. Embo J 8 4099 4105

14. LiuX

ClementsA

ZhaoK

MarmorsteinR

2006 Structure of the human Papillomavirus E7 oncoprotein and its mechanism for inactivation of the retinoblastoma tumor suppressor. J Biol Chem 281 578 586

15. HeltAM

GallowayDA

2001 Destabilization of the retinoblastoma tumor suppressor by human papillomavirus type 16 E7 is not sufficient to overcome cell cycle arrest in human keratinocytes. J Virol 75 6737 6747

16. DysonN

GuidaP

MungerK

HarlowE

1992 Homologous sequences in adenovirus E1A and human papillomavirus E7 proteins mediate interaction with the same set of cellular proteins. J Virol 66 6893 6902

17. ClemensKE

BrentR

GyurisJ

MungerK

1995 Dimerization of the human papillomavirus E7 oncoprotein in vivo. Virology 214 289 293

18. BrehmA

NielsenSJ

MiskaEA

McCanceDJ

ReidJL

1999 The E7 oncoprotein associates with Mi2 and histone deacetylase activity to promote cell growth. Embo J 18 2449 2458

19. MungerK

BasileJR

DuensingS

EichtenA

GonzalezSL

2001 Biological activities and molecular targets of the human papillomavirus E7 oncoprotein. Oncogene 20 7888 7898

20. HuangPS

PatrickDR

EdwardsG

GoodhartPJ

HuberHE

1993 Protein domains governing interactions between E2F, the retinoblastoma gene product, and human papillomavirus type 16 E7 protein. Mol Cell Biol 13 953 960

21. WuEW

ClemensKE

HeckDV

MungerK

1993 The human papillomavirus E7 oncoprotein and the cellular transcription factor E2F bind to separate sites on the retinoblastoma tumor suppressor protein. J Virol 67 2402 2407

22. RectorA

BossartGD

GhimSJ

SundbergJP

JensonAB

2004 Characterization of a novel close-to-root papillomavirus from a Florida manatee by using multiply primed rolling-circle amplification: Trichechus manatus latirostris papillomavirus type 1. J Virol 78 12698 12702

23. Moreno-LopezJ

AholaH

StenlundA

OsterhausA

PetterssonU

1984 Genome of an avian papillomavirus. J Virol 51 872 875

24. YuanH

EstesPA

ChenY

NewsomeJ

OlceseVA

2001 Immunization with a pentameric L1 fusion protein protects against papillomavirus infection. J Virol 75 7848 7853

25. StanleyMA

MooreRA

NichollsPK

SantosEB

ThomsenL

2001 Intra-epithelial vaccination with COPV L1 DNA by particle-mediated DNA delivery protects against mucosal challenge with infectious COPV in beagle dogs. Vaccine 19 2783 2792

26. DisbrowGL

BaegeAC

KierpiecKA

YuanH

CentenoJA

2005 Dihydroartemisinin is cytotoxic to papillomavirus-expressing epithelial cells in vitro and in vivo. Cancer Res 65 10854 10861

27. YuanH

GhimS

NewsomeJ

ApolinarioT

OlceseV

2007 An epidermotropic canine papillomavirus with malignant potential contains an E5 gene and establishes a unique genus. Virology 359 28 36

28. GoldschmidtMH

KennedyJS

KennedyDR

YuanH

HoltDE

2006 Severe papillomavirus infection progressing to metastatic squamous cell carcinoma in bone marrow-transplanted X-linked SCID dogs. J Virol 80 6621 6628

29. SparkowskiJ

AndersJ

SchlegelR

1994 Mutation of the bovine papillomavirus E5 oncoprotein at amino acid 17 generates both high- and low-transforming variants. J Virol 68 6120 6123

30. SchlegelR

PhelpsWC

ZhangYL

BarbosaM

1988 Quantitative keratinocyte assay detects two biological activities of human papillomavirus DNA and identifies viral types associated with cervical carcinoma. Embo J 7 3181 3187

31. YuanH

VeldmanT

RundellK

SchlegelR

2002 Simian virus 40 small tumor antigen activates AKT and telomerase and induces anchorage-independent growth of human epithelial cells. J Virol 76 10685 10691

32. TamuraK

DudleyJ

NeiM

KumarS

2007 MEGA4: Molecular Evolutionary Genetics Analysis (MEGA) software version 4.0. Mol Biol Evol 24 1596 1599

33. JonesRE

WegrzynRJ

PatrickDR

BalishinNL

VuocoloGA

1990 Identification of HPV-16 E7 peptides that are potent antagonists of E7 binding to the retinoblastoma suppressor protein. J Biol Chem 265 12782 12785

34. ForngRY

AtreyaCD

1999 Mutations in the retinoblastoma protein-binding LXCXE motif of rubella virus putative replicase affect virus replication. J Gen Virol 80 (Pt 2) 327 332

35. MungerK

HalpernAL

1997 hpv e7 primary structure and biological properties

36. PatrickDR

OliffA

HeimbrookDC

1994 Identification of a novel retinoblastoma gene product binding site on human papillomavirus type 16 E7 protein. J Biol Chem 269 6842 6850

37. StopplerH

StopplerMC

AdduciA

KovalD

SchlegelR

1996 The serine protease inhibitors TLCK and TPCK react with the RB-binding core of HPV-18 E7 protein and abolish its RB-binding capability. Virology 217 542 553

38. MungerK

BaldwinA

EdwardsKM

HayakawaH

NguyenCL

2004 Mechanisms of human papillomavirus-induced oncogenesis. J Virol 78 11451 11460

39. de VilliersE-M

FauquetC

BrokerTR

BernardH-U

zur HausenH

2004 Classification of papillomaviruses. Virology 324 17 27

40. ThompsonJD

HigginsDG

GibsonTJ

1994 CLUSTAL W: improving the sensitivity of progressive multiple sequence alignment through sequence weighting, position-specific gap penalties and weight matrix choice. Nucleic Acids Res 22 4673 4680

41. FelsaniA

MileoAM

PaggiMG

2006 Retinoblastoma family proteins as key targets of the small DNA virus oncoproteins. Oncogene 25 5277 5285

42. LangeCE

ToblerK

AckermannM

PanakovaL

ThodayKL

2009 Three novel canine papillomaviruses support taxonomic clade formation. J Gen Virol

Štítky
Hygiena a epidemiológia Infekčné lekárstvo Laboratórium

Článok vyšiel v časopise

PLOS Pathogens


2010 Číslo 9
Najčítanejšie tento týždeň
Najčítanejšie v tomto čísle
Kurzy

Zvýšte si kvalifikáciu online z pohodlia domova

Aktuální možnosti diagnostiky a léčby litiáz
nový kurz
Autori: MUDr. Tomáš Ürge, PhD.

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#