TOPO3α Influences Antigenic Variation by Monitoring Expression-Site-Associated Switching in

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Homologous recombination (HR) mediates one of the major mechanisms of trypanosome antigenic variation by placing a different variant surface glycoprotein (VSG) gene under the control of the active expression site (ES). It is believed that the majority of VSG switching events occur by duplicative gene conversion, but only a few DNA repair genes that are central to HR have been assigned a role in this process. Gene conversion events that are associated with crossover are rarely seen in VSG switching, similar to mitotic HR. In other organisms, TOPO3α (Top3 in yeasts), a type IA topoisomerase, is part of a complex that is involved in the suppression of crossovers. We therefore asked whether a related mechanism might suppress VSG recombination. Using a set of reliable recombination and switching assays that could score individual switching mechanisms, we discovered that TOPO3α function is conserved in Trypanosoma brucei and that TOPO3α plays a critical role in antigenic switching. Switching frequency increased 10–40-fold in the absence of TOPO3α and this hyper-switching phenotype required RAD51. Moreover, the preference of 70-bp repeats for VSG recombination was mitigated, while homology regions elsewhere in ES were highly favored, in the absence of TOPO3α. Our data suggest that TOPO3α may remove undesirable recombination intermediates constantly arising between active and silent ESs, thereby balancing ES integrity against VSG recombination.

Vyšlo v časopise: TOPO3α Influences Antigenic Variation by Monitoring Expression-Site-Associated Switching in. PLoS Pathog 6(7): e32767. doi:10.1371/journal.ppat.1000992
Kategorie: Research Article
prolekare.web.journal.doi_sk: https://doi.org/10.1371/journal.ppat.1000992

Souhrn

Zdroje

1. MarcelloL

BarryJD

2007 Analysis of the VSG gene silent archive in Trypanosoma brucei reveals that mosaic gene expression is prominent in antigenic variation and is favored by archive substructure. Genome Res 17 1344 1352

2. MarcelloL

MenonS

WardP

WilkesJM

JonesNG

2007 VSGdb: a database for trypanosome variant surface glycoproteins, a large and diverse family of coiled coil proteins. BMC Bioinformatics 8 143

3. HornD

BarryJD

2005 The central roles of telomeres and subtelomeres in antigenic variation in African trypanosomes. Chrom Res 13 525 533

4. BarryJD

McCullochR

2001 Antigenic variation in trypanosomes: enhanced phenotypic variation in a eukaryotic parasite.

BakerJR

MullerR

RollinsonD

Advances in Parasitology 49 London Academic Press Ltd 1 70

5. CrossGAM

2002 Antigenic variation in african trypanosomes and malaria.

MarrJ

KoumunieckiR

NilsenTW

Mol Med Parasitol Academic Press 89 110

6. RudenkoG

BishopD

GottesdienerK

van der PloegLHT

1989 Alpha-amanitin resistant transcription of protein coding genes in insect and bloodstream form Trypanosoma brucei. EMBO J 8 4259 4263

7. PalencharJ

BellofattoV

2006 Gene transcription in trypanosomes. Mol Biochem Parasitol 146 135 141

8. GunzlA

BrudererT

LauferG

SchimanskiB

TuLC

2003 RNA polymerase I transcribes procyclin genes and variant surface glycoprotein gene expression sites in Trypanosoma brucei. Eukaryot Cell 2 542 551

9. Hertz-FowlerC

FigueiredoLM

QuailMA

BeckerM

JacksonA

2008 Telomeric expression sites are highly conserved in Trypanosoma brucei. PLoS ONE 3 e3527

10. MachadoC

Augusto-PintoL

McCullochR

TeixeiraS

2006 DNA metabolism and genetic diversity in Trypanosomes. Mutat Res Rev-Mutat Res 612 40 57

11. ZomerdijkJCBM

OuelleteM

ten AsbroekALMA

KieftR

BommerAMM

1990 The promoter for a variant surface glycoprotein gene expression site in Trypanosoma brucei. EMBO J 9 2791 2801

12. JohnsonPJ

BorstP

1986 Mapping of VSG genes on large expression-site chromosomes of Trypanosoma brucei separated by pulse-field gradient electrophoresis. Gene 43 213 220

13. PaysE

van AsselS

LaurentM

DarvilleM

VervoortT

1983 Gene conversion as a mechanism for antigenic variation in trypanosomes. Cell 34 371 381

14. MylerP

NelsonRG

AgabianN

StuartK

1984 Two mechanisms of expression of a variant antigen gene of Trypanosoma brucei. Nature 309 282 284

15. LeeMG-S

van der PloegLHT

1987 Frequent independent duplicative transpositions activate a single VSG gene. Mol Cell Biol 7 357 364

16. de LangeT

KooterJM

MichelsPAM

BorstP

1983 Telomere conversion in trypanosomes. Nucl Acids Res 11 8149 8165

17. RobinsonNP

BurmanN

MelvilleSE

BarryJD

1999 Predominance of duplicative VSG gene conversion in antigenic variation in African trypanosomes. Mol Cell Biol 19 5839 5846

18. HoeijmakersJHJ

FraschACC

BernardsA

BorstP

CrossGAM

1980 Novel expression-linked copies of the genes for variant surface antigens in trypanosomes. Nature 284 78 80

19. PaysE

GuyauxM

AertsD

vanMeirvenneN

SteinertM

1985 Telomeric reciprocal recombination as a possible mechanism for antigenic variation in trypanosomes. Nature 316 562 564

20. AitchesonN

TalbotS

ShapiroJ

HughesK

AdkinC

2005 VSG switching in Trypanosoma brucei: antigenic variation analysed using RNAi in the absence of immune selection. Mol Microbiol 57 1608 1622

21. RudenkoG

McCullochR

DirksmulderA

BorstP

1996 Telomere exchange can be an important mechanism of variant surface glycoprotein gene switching in Trypanosoma brucei. Mol Biochem Parasitol 80 65 75

22. BernardsA

van der PloegLHT

GibsonWC

LeegwaterP

EijgenraamF

1986 Rapid change of the repertoire of variant surface glycoprotein genes in trypanosomes by gene duplication and deletion. J Mol Biol 190 1 10

23. ProudfootC

McCullochR

2005 Distinct roles for two RAD51-related genes in Trypanosoma brucei antigenic variation. Nucl Acids Res 33 6906 6919

24. McCullochR

BarryJD

1999 A role for RAD51 and homologous recombination in Trypanosoma brucei antigenic variation. Genes Dev 13 2875 2888

25. HartleyCL

McCullochR

2008 Trypanosoma brucei BRCA2 acts in antigenic variation and has undergone a recent expansion in BRC repeat number that is important during homologous recombination. Mol Microbiol 68 1237 1251

26. D'AmoursD

JacksonSP

2002 The Mre11 complex: at the crossroads of DNA repair and checkpoint signalling. Nat Rev Mol Cell Biol 3 317 327

27. WilliamsRS

MoncalianG

WilliamsJS

YamadaY

LimboO

2008 Mre11 dimers coordinate DNA end bridging and nuclease processing in double-strand-break repair. Cell 135 97 109

28. KanaarR

WymanC

2008 DNA repair by the MRN complex: break it to make it. Cell 135 14 16

29. TanKSW

LealSLG

CrossGAM

2002 Trypanosoma brucei MRE11 is non-essential but influences growth, homologous recombination and DNA double-strand break repair. Mol Biochem Parasitol 125 11 21

30. RobinsonNP

McCullochR

ConwayC

BrowittA

BarryJD

2002 Inactivation of Mre11 does not affect VSG gene duplication mediated by homologous recombination in Trypanosoma brucei. J Biol Chem 277 26185 26193

31. IraG

MalkovaA

LiberiG

FoianiM

HaberJE

2003 Srs2 and Sgs1-Top3 suppress crossovers during double-strand break repair in yeast. Cell 115 401 411

32. BachratiCZ

HicksonID

2008 RecQ helicases: guardian angels of the DNA replication fork. Chromosoma 117 219 233

33. SekiM

TadaS

EnomotoT

2006 Function of recQ family helicase in genome stability. Subcell Biochem 40 49 73

34. SungP

KleinH

2006 Mechanism of homologous recombination: mediators and helicases take on regulatory functions. Nat Rev Mol Cell Biol 7 739 750

35. ChangM

BellaouiM

ZhangC

DesaiR

MorozovP

2005 RMI1/NCE4, a suppressor of genome instability, encodes a member of the RecQ helicase/Topo III complex. EMBO J 24 2024 2033

36. MullenJR

NallasethFS

LanYQ

SlagleCE

BrillSJ

2005 Yeast Rmi1/Nce4 controls genome stability as a subunit of the Sgs1-Top3 complex. Mol Cell Biol 25 4476 4487

37. TsaiHJ

HuangWH

LiTK

TsaiYL

WuKJ

2006 Involvement of topoisomerase III in telomere-telomere recombination. J Biol Chem 281 13717 13723

38. HuangPH

PrydeFE

LesterD

MaddisonRL

BortsRH

2001 SGS1 is required for telomere elongation in the absence of telomerase. Curr Biol 11 125 129

39. NeffNF

EllisNA

YeTZ

NoonanJ

HuangK

1999 The DNA helicase activity of BLM is necessary for the correction of the genomic instability of bloom syndrome cells. Mol Biol Cell 10 665 676

40. SinghTR

AliAM

BusyginaV

RaynardS

FanQ

2008 BLAP18/RMI2, a novel OB-fold-containing protein, is an essential component of the Bloom helicase-double Holliday junction dissolvasome. Genes Dev 22 2856 2868

41. XuD

GuoR

SobeckA

BachratiCZ

YangJ

2008 RMI, a new OB-fold complex essential for Bloom syndrome protein to maintain genome stability. Genes Dev 22 2843 2855

42. WattPM

HicksonID

BortsRH

LouisEJ

1996 SGS1, a homologue of the Bloom's and Werner's syndrome genes, is required for maintenance of genome stability in Saccharomyces cerevisiae. Genetics 144 935 945

43. WallisJW

ChrebetG

BrodskyG

RolfeM

RothsteinR

1989 A hyper-recombination mutation in S. cerevisiae identifies a novel eukaryotic topoisomerase. Cell 58 409 419

44. WuL

HicksonID

2003 The Bloom's syndrome helicase suppresses crossing over during homologous recombination. Nature 426 870 874

45. HartungF

SuerS

KnollA

Wurz-WildersinnR

PuchtaH

2008 Topoisomerase 3alpha and RMI1 suppress somatic crossovers and are essential for resolution of meiotic recombination intermediates in Arabidopsis thaliana. PLoS Genet 4 e1000285

46. SekiM

NakagawaT

SekiT

KatoG

TadaS

2006 Bloom helicase and DNA topoisomerase IIIalpha are involved in the dissolution of sister chromatids. Mol Cell Biol 26 6299 6307

47. ChampouxJJ

2001 DNA topoisomerases: structure, function, and mechanism. Annu Rev Biochem 70 369 413

48. ScahillMD

PastarI

CrossGA

2008 CRE recombinase-based positive-negative selection systems for genetic manipulation in Trypanosoma brucei. Mol Biochem Parasitol 157 73 82

49. MaftahiM

HanCS

LangstonLD

HopeJC

ZigourasN

1999 The top3(+) gene is essential in Schizosaccharomyces pombe and the lethality associated with its loss is caused by Rad12 helicase activity. Nucl Acids Res 27 4715 4724

50. LiW

WangJC

1998 Mammalian DNA topoisomerase IIIalpha is essential in early embryogenesis. Proc Natl Acad Sci U S A 95 1010 1013

51. KwanKY

WangJC

2001 Mice lacking DNA topoisomerase IIIbeta develop to maturity but show a reduced mean lifespan. Proc Natl Acad Sci U S A 98 5717 5721

52. OakleyTJ

GoodwinA

ChakravertyRK

HicksonID

2002 Inactivation of homologous recombination suppresses defects in topoisomerase III-deficient mutants. DNA repair 1 463 482

53. OhM

ChoiIS

ParkSD

2002 Topoisomerase III is required for accurate DNA replication and chromosome segregation in Schizosaccharomyces pombe. Nucl Acids Res 30 4022 4031

54. ChakravertyRK

KearseyJM

OakleyTJ

GrenonM

de La Torre RuizMA

2001 Topoisomerase III acts upstream of Rad53p in the S-phase DNA damage checkpoint. Mol Cell Biol 21 7150 7162

55. DaviesKP

CarruthersVB

CrossGAM

1997 Manipulation of the VSG co-transposed region increases expression-site switching in Trypanosoma brucei. Mol Biochem Parasitol 86 163 177

56. BoothroydCE

DreesenO

LeonovaT

LyKI

FigueiredoLM

2009 A yeast-endonuclease-generated DNA break induces antigenic switching in Trypanosoma brucei. Nature 459 278 281

57. LiberiG

MaffiolettiG

LuccaC

ChioloI

BaryshnikovaA

2005 Rad51-dependent DNA structures accumulate at damaged replication forks in sgs1 mutants defective in the yeast ortholog of BLM RecQ helicase. Genes Dev 19 339 350

58. MankouriHW

HicksonID

2006 Top3 processes recombination intermediates and modulates checkpoint activity after DNA damage. Mol Biol Cell 17 4473 4483

59. VanhammeL

PoelvoordeP

PaysA

TebabiP

XongHV

2000 Differential RNA elongation controls the variant surface glycoprotein gene expression sites of Trypanosoma brucei. Mol Microbiol 36 328 340

60. CrossM

TaylorMC

BorstP

1998 Frequent loss of the active site during variant surface glycoprotein expression site switching in vitro in Trypanosoma brucei. Mol Cell Biol 18 198 205

61. BitterW

GerritsH

KieftR

BorstP

1998 The role of transferrin-receptor variation in the host range of Trypanosoma brucei. Nature 391 499 502

62. McCullochR

RudenkoG

BorstP

1997 Gene conversions mediating antigenic variation in Trypanosoma brucei can occur in variant surface glycoprotein expression sites lacking 70-base-pair repeat sequences. Mol Cell Biol 17 833 843

63. OhshimaK

KangS

LarsonJE

WellsRD

1996 TTA.TAA triplet repeats in plasmids form a non-H bonded structure. J Biol Chem 271 16784 16791

64. KooterJM

WinterAJ

de OliveiraC

WagterR

BorstP

1988 Boundaries of telomere conversion in Trypanosoma brucei. Gene 69 1 11

65. LiuAY

MichelsPA

BernardsA

BorstP

1985 Trypanosome variant surface glycoprotein genes expressed early in infection. J Mol Biol 175 383 386

66. TimmersHTM

de LangeT

KooterJM

BorstP

1987 Coincident multiple activations of the same surface antigen gene in Trypanosoma brucei. J Mol Biol 184 81 90

67. AlineRF

StuartKD

1989 Trypanosoma brucei: conserved sequence organisation 3′ to telomeric variant surface glycoprotein genes. Exp Parasitol 68 57 66

68. GangloffS

McDonaldJP

BendixenC

ArthurL

RothsteinR

1994 The yeast type I topoisomerase Top3 interacts with Sgs1, a DNA helicase homolog: a potential eukaryotic reverse gyrase. Mol Cell Biol 14 8391 8398

69. ShorE

GangloffS

WagnerM

WeinsteinJ

PriceG

2002 Mutations in homologous recombination genes rescue top3 slow growth in Saccharomyces cerevisiae. Genetics 162 647 662

70. ConwayC

McCullochR

GingerML

RobinsonNP

BrowittA

2002 Ku is important for telomere maintenance, but not for differential expression of telomeric VSG genes, in African trypanosomes. J Biol Chem 277 21269 21277

71. BellJS

McCullochR

2003 Mismatch repair regulates homologous recombination, but has little influence on antigenic variation, in Trypanosoma brucei. J Biol Chem 278 45182 45188

72. ChenCF

BrillSJ

2007 Binding and activation of DNA topoisomerase III by the Rmi1 subunit. J Biol Chem 282 28971 28979

73. MullenJR

KaliramanV

IbrahimSS

BrillSJ

2001 Requirement for three novel protein complexes in the absence of the Sgs1 DNA helicase in Saccharomyces cerevisiae. Genetics 157 103 118

74. Bastin-ShanowerSA

FrickeWM

MullenJR

BrillSJ

2003 The mechanism of Mus81-Mms4 cleavage site selection distinguishes it from the homologous endonuclease Rad1-Rad10. Mol Cell Biol 23 3487 3496

75. KaliramanV

MullenJR

FrickeWM

Bastin-ShanowerSA

BrillSJ

2001 Functional overlap between Sgs1-Top3 and the Mms4-Mus81 endonuclease. Genes Dev 15 2730 2740

76. CoteAG

LewisSM

2008 Mus81-dependent double-strand DNA breaks at in vivo-generated cruciform structures in S. cerevisiae. Mol Cell 31 800 812

77. IpSC

RassU

BlancoMG

FlynnHR

SkehelJM

2008 Identification of Holliday junction resolvases from humans and yeast. Nature 456 357 361

78. SurteesJA

ArguesoJL

AlaniE

2004 Mismatch repair proteins: key regulators of genetic recombination. Cytogenet Genome Res 107 146 159

79. CobbJA

SchlekerT

RojasV

BjergbaekL

TerceroJA

2005 Replisome instability, fork collapse, and gross chromosomal rearrangements arise synergistically from Mec1 kinase and RecQ helicase mutations. Genes Dev 19 3055 3069

80. GottipatiP

HelledayT

2009 Transcription-associated recombination in eukaryotes: link between transcription, replication and recombination. Mutagenesis 24 203 210

81. AlsfordS

HornD

2007 RNA polymerase I transcription stimulates homologous recombination in Trypanosoma brucei. Mol Biochem Parasitol 153 77 79

82. AlsfordS

HornD

2008 Single-locus targeting constructs for reliable regulated RNAi and transgene expression in Trypanosoma brucei. Mol Biochem Parasitol 161 76 79

83. Gonzalez-BarreraS

Garcia-RubioM

AguileraA