#PAGE_PARAMS# #ADS_HEAD_SCRIPTS# #MICRODATA#

Genetic and Biochemical Assays Reveal a Key Role for Replication Restart Proteins in Group II Intron Retrohoming


Mobile group II introns retrohome by an RNP-based mechanism in which the intron RNA reverse splices into a DNA site and is reverse transcribed by the associated intron-encoded protein. The resulting intron cDNA is then integrated into the genome by cellular mechanisms that have remained unclear. Here, we used an Escherichia coli genetic screen and Taqman qPCR assay that mitigate indirect effects to identify host factors that function in retrohoming. We then analyzed mutants identified in these and previous genetic screens by using a new biochemical assay that combines group II intron RNPs with cellular extracts to reconstitute the complete retrohoming reaction in vitro. The genetic and biochemical analyses indicate a retrohoming pathway involving degradation of the intron RNA template by a host RNase H and second-strand DNA synthesis by the host replicative DNA polymerase. Our results reveal ATP-dependent steps in both cDNA and second-strand synthesis and a surprising role for replication restart proteins in initiating second-strand synthesis in the absence of DNA replication. We also find an unsuspected requirement for host factors in initiating reverse transcription and a new RNA degradation pathway that suppresses retrohoming. Key features of the retrohoming mechanism may be used by human LINEs and other non-LTR-retrotransposons, which are related evolutionarily to mobile group II introns. Our findings highlight a new role for replication restart proteins, which function not only to repair DNA damage caused by mobile element insertion, but have also been co-opted to become an integral part of the group II intron retrohoming mechanism.


Vyšlo v časopise: Genetic and Biochemical Assays Reveal a Key Role for Replication Restart Proteins in Group II Intron Retrohoming. PLoS Genet 9(4): e32767. doi:10.1371/journal.pgen.1003469
Kategorie: Research Article
prolekare.web.journal.doi_sk: https://doi.org/10.1371/journal.pgen.1003469

Souhrn

Mobile group II introns retrohome by an RNP-based mechanism in which the intron RNA reverse splices into a DNA site and is reverse transcribed by the associated intron-encoded protein. The resulting intron cDNA is then integrated into the genome by cellular mechanisms that have remained unclear. Here, we used an Escherichia coli genetic screen and Taqman qPCR assay that mitigate indirect effects to identify host factors that function in retrohoming. We then analyzed mutants identified in these and previous genetic screens by using a new biochemical assay that combines group II intron RNPs with cellular extracts to reconstitute the complete retrohoming reaction in vitro. The genetic and biochemical analyses indicate a retrohoming pathway involving degradation of the intron RNA template by a host RNase H and second-strand DNA synthesis by the host replicative DNA polymerase. Our results reveal ATP-dependent steps in both cDNA and second-strand synthesis and a surprising role for replication restart proteins in initiating second-strand synthesis in the absence of DNA replication. We also find an unsuspected requirement for host factors in initiating reverse transcription and a new RNA degradation pathway that suppresses retrohoming. Key features of the retrohoming mechanism may be used by human LINEs and other non-LTR-retrotransposons, which are related evolutionarily to mobile group II introns. Our findings highlight a new role for replication restart proteins, which function not only to repair DNA damage caused by mobile element insertion, but have also been co-opted to become an integral part of the group II intron retrohoming mechanism.


Zdroje

1. LambowitzAM, ZimmerlyS (2011) Group II introns: mobile ribozymes that invade DNA. Cold Spring Harb Perspect Biol 3: a003616 doi:10.1101/cshperspect.a003616.

2. ZimmerlyS, GuoH, EskesR, YangJ, PerlmanPS, et al. (1995) A group II intron RNA is a catalytic component of a DNA endonuclease involved in intron mobility. Cell 83: 529–538.

3. ZimmerlyS, GuoH, PerlmanPS, LambowitzAM (1995) Group II intron mobility occurs by target DNA-primed reverse transcription. Cell 82: 545–554.

4. YangJ, ZimmerlyS, PerlmanPS, LambowitzAM (1996) Efficient integration of an intron RNA into double-stranded DNA by reverse splicing. Nature 381: 332–335.

5. CousineauB, SmithD, Lawrence-CavanaghS, MuellerJE, YangJ, et al. (1998) Retrohoming of a bacterial group II intron: mobility via complete reverse splicing, independent of homologous DNA recombination. Cell 94: 451–462.

6. Belfort M, Derbyshire V, Parker MM, Cousineau B, Lambowitz AM (2002) Mobile introns: pathways and proteins. In: Craig N, Craigie R, Gellert M, Lambowitz AM, editors. Mobile DNA II. Washington DC: ASM Press. pp. 761–783.

7. Eickbush TH, Malik HS (2002) Evolution of retrotransposons. In: Craig N, Craigie R, Gellert M, Lambowitz AM, editors. Mobile DNA II. Washinton DC: ASM Press. pp. 1111–1114.

8. KooninEV (2009) Intron-dominated genomes of early ancestors of eukaryotes. J Hered 100: 618–623.

9. EskesR, YangJ, LambowitzAM, PerlmanPS (1997) Mobility of yeast mitochondrial group II introns: engineering a new site specificity and retrohoming via full reverse splicing. Cell 88: 865–874.

10. EskesR, LiuL, MaH, ChaoMY, DicksonL, et al. (2000) Multiple homing pathways used by yeast mitochondrial group II introns. Mol Cell Biol 20: 8432–8446.

11. MillsDA, ManiasDA, McKayLL, DunnyGM (1997) Homing of a group II intron from Lactococcus lactis subsp. lactis ML3. J Bacteriol 179: 6107–6111.

12. SmithD, ZhongJ, MatsuuraM, LambowitzAM, BelfortM (2005) Recruitment of host functions suggests a repair pathway for late steps in group II intron retrohoming. Genes Dev 19: 2477–2487.

13. WhiteTB, LambowitzAM (2012) The retrohoming of linear group II intron RNAs in Drosophila melanogaster occurs by both DNA ligase 4-dependent and -independent mechanisms. PLoS Genet 8: e1002534 doi:10.1371/journal.pgen.1002534.

14. MillsDA, McKayLL, DunnyGM (1996) Splicing of a group II intron involved in the conjugative transfer of pRS01 in Lactococci. J Bacteriol 178: 3531–3538.

15. ShearmanC, GodonJJ, GassonM (1996) Splicing of a group II intron in a functional transfer gene of Lactococcus lactis. Mol Microbiol 21: 45–53.

16. MatsuuraM, SaldanhaR, MaH, WankH, YangJ, et al. (1997) A bacterial group II intron encoding reverse transcriptase, maturase, and DNA endonuclease activities: biochemical demonstration of maturase activity and insertion of new genetic information within the intron. Genes Dev 11: 2910–2924.

17. SaldanhaR, ChenB, WankH, MatsuuraM, EdwardsJ, et al. (1999) RNA and protein catalysis in group II intron splicing and mobility reactions using purified components. Biochemistry 38: 9069–9083.

18. MatsuuraM, NoahJW, LambowitzAM (2001) Mechanism of maturase-promoted group II intron splicing. EMBO J 20: 7259–7270.

19. GuoH, KarbergM, LongM, JonesJPIII, SullengerB, et al. (2000) Group II introns designed to insert into therapeutically relevant DNA target sites in human cells. Science 289: 452–457.

20. MohrG, SmithD, BelfortM, LambowitzAM (2000) Rules for DNA target-site recognition by a lactococcal group II intron enable retargeting of the intron to specific DNA sequences. Genes Dev 14: 559–573.

21. PerutkaJ, WangW, GoerlitzD, LambowitzAM (2004) Use of computer-designed group II introns to disrupt Escherichia coli DExH/D-box protein and DNA helicase genes. J Mol Biol 336: 421–439.

22. CorosCJ, PiazzaCL, ChalamcharlaVR, BelfortM (2008) A mutant screen reveals RNase E as a silencer of group II intron retromobility in Escherichia coli. RNA 14: 2634–2644.

23. CorosCJ, PiazzaCL, ChalamcharlaVR, SmithD, BelfortM (2009) Global regulators orchestrate group II intron retromobility. Mol Cell 34: 250–256.

24. ZhongJ, KarbergM, LambowitzAM (2003) Targeted and random bacterial gene disruption using a group II intron (targetron) vector containing a retrotransposition-activated selectable marker. Nucleic Acids Res 31: 1656–1664.

25. LiuYG, WhittierRF (1995) Thermal asymmetric interlaced PCR: automatable amplification and sequencing of insert end fragments from P1 and YAC clones for chromosome walking. Genomics 25: 674–681.

26. KarbergM, GuoH, ZhongJ, CoonR, PerutkaJ, et al. (2001) Group II introns as controllable gene targeting vectors for genetic manipulation of bacteria. Nat Biotechnol 19: 1162–1167.

27. OhmoriH (1994) Structural analysis of the rhlE gene of Escherichia coli. Jpn J Genet 69: 1–12.

28. YaoJ, LambowitzAM (2007) Gene targeting in gram-negative bacteria by use of a mobile group II intron (“targetron”) expressed from a broad-host-range vector. Appl Environ Microbiol 73: 2735–2743.

29. BabaT, AraT, HasegawaM, TakaiY, OkumuraY, et al. (2006) Construction of Escherichia coli K-12 in-frame, single-gene knockout mutants: the Keio collection. Mol Syst Biol 2: 2006.0008 doi:10.1038/msb4100050.

30. BeauregardA, ChalamcharlaVR, PiazzaCL, BelfortM, CorosCJ (2006) Bipolar localization of the group II intron Ll.LtrB is maintained in Escherichia coli deficient in nucleoid condensation, chromosome partitioning and DNA replication. Mol Microbiol 62: 709–722.

31. KanayaS, CrouchRJ (1983) DNA sequence of the gene coding for Escherichia coli ribonuclease H. J Biol Chem 258: 1276–1281.

32. UyemuraD, EichlerDC, LehmanIR (1976) Biochemical characterization of mutant forms of DNA polymerase I from Escherichia coli. II. The PolAex1 mutation. J Biol Chem 251: 4085–4089.

33. MakiH, KornbergA (1985) The polymerase subunit of DNA polymerase III of Escherichia coli. II. Purification of the a subunit, devoid of nuclease activities. J Biol Chem 260: 12987–12992.

34. RydbergB, GameJ (2002) Excision of misincorporated ribonucleotides in DNA by RNase H (type 2) and FEN-1 in cell-free extracts. Proc Natl Acad Sci U S A 99: 16654–16659.

35. LovettST, ClarkAJ (1984) Genetic analysis of the recJ gene of Escherichia coli K-12. J Bacteriol 157: 190–196.

36. DiFrancescoR, BhatnagarSK, BrownA, BessmanMJ (1984) The interaction of DNA polymerase III and the product of the Escherichia coli mutator gene, mutD. J Biol Chem 259: 5567–5573.

37. TakahashiS, HoursC, ChuA, DenhardtDT (1979) The rep mutation. VI. Purification and properties of the Escherichia coli rep protein, DNA helicase III. Can J Biochem 57: 855–866.

38. UmezuK, NakayamaK, NakayamaH (1990) Escherichia coli RecQ protein is a DNA helicase. Proc Natl Acad Sci U S A 87: 5363–5367.

39. CusickME, BelfortM (1998) Domain structure and RNA annealing activity of the Escherichia coli regulatory protein StpA. Mol Microbiol 28: 847–857.

40. OliveraBM, LehmanIR (1967) Linkage of polynucleotides through phosphodiester bonds by an enzyme from Escherichia coli. Proc Natl Acad Sci U S A 57: 1426–1433.

41. SriskandaV, ShumanS (2001) A second NAD+-dependent DNA ligase (LigB) in Escherichia coli. Nucleic Acids Res 29: 4930–4934.

42. KinscherfTG, ApirionD (1975) Polynucleotide phosphorylase can participate in decay of mRNA in Escherichia coli in the absence of ribonuclease II. Mol Gen Genet 139: 357–362.

43. KornbergT, GefterML (1971) Purification and DNA synthesis in cell-free extracts: properties of DNA polymerase II. Proc Natl Acad Sci U S A 68: 761–764.

44. WagnerJ, GruzP, KimS-R, YamadaM, MatsuiK, et al. (1999) The dinB gene encodes a novel E. coli DNA polymerase, DNA Pol IV, involved in mutagenesis. Mol Cell 4: 281–286.

45. ShinagawaH, KatoT, IseT, MakinoK, NakataA (1983) Cloning and characterization of the umu operon responsible for inducible mutagenesis in Escherichia coli. Gene 23: 167–174.

46. MasaiH, AraiK (1988) Operon structure of dnaT and dnaC genes essential for normal and stable DNA replication of Escherichia coli chromosome. J Biol Chem 263: 15083–15093.

47. HellerRC, MariansKJ (2005) The disposition of nascent strands at stalled replication forks dictates the pathway of replisome loading during restart. Mol Cell 17: 733–743.

48. CuiX, MatsuuraM, WangQ, MaH, LambowitzAM (2004) A group II intron-encoded maturase functions preferentially in cis and requires both the reverse transcriptase and X domains to promote RNA splicing. J Mol Biol 340: 211–231.

49. OtsukaY, YonesakiT (2005) A novel endoribonuclease, RNase LS, in Escherichia coli. Genetics 169: 13–20.

50. WangX, KimY, WoodTK (2009) Control and benefits of CP4-57 prophage excision in Escherichia coli biofilms. ISME J 3: 1164–1179.

51. CarpousisAJ (2007) The RNA degradosome of Escherichia coli: an mRNA-degrading machine assembled on RNase E. Annu Rev Genet 61: 71–87.

52. LiuJ, XuL, SandlerSJ, MariansKJ (1999) Replication fork assembly at recombination intermediates is required for bacterial growth. Proc Natl Acad Sci U S A 96: 3552–3555.

53. UedaK, McMackenR, KornbergA (1978) DnaB protein of Escherichia coli. Purification and role in the replication of φX174 DNA. J Biol Chem 253: 261–269.

54. AllenGCJr, KornbergA (1993) Assembly of the primosome of DNA replication in Escherichia coli. J Biol Chem 268: 19204–19209.

55. WahleE, LaskenRS, KornbergA (1989) The dnaB-dnaC replication protein complex of Escherichia coli. I. Formation and properties. J Biol Chem 264: 2463–2468.

56. RowenL, KornbergA (1978) Primase, the dnaG protein of Escherichia coli. An enzyme which starts DNA chains. J Biol Chem 253: 758–764.

57. MeyerRR, LainePS (1990) The single-stranded DNA-binding protein of Escherichia coli. Microbiol Mol Biol Rev 54: 342–380.

58. CadmanCJ, McGlynnP (2004) PriA helicase and SSB interact physically and functionally. Nucleic Acids Res 32: 6378–6387.

59. SandlerSJ (2000) Multiple genetic pathways for restarting DNA replication forks in Escherichia coli K-12. Genetics 155: 487–497.

60. McCoolJD, LongE, PetrosinoJF, SandlerHA, RosenbergSM, et al. (2004) Measurement of SOS expression in individual Escherichia coli K-12 cells using fluorescence microscopy. Mol Microbiol 53: 1343–1357.

61. YamaneT, IkedaY, NagasakaT, NakanoH (2005) Enhanced cell-free protein synthesis using a S30 extract from Escherichia coli grown rapidly at 42°C in an amino acid enriched medium. Biotechnol Prog 21: 608–613.

62. KimT-W, KeumJ-W, OhI-S, ChoiC-Y, ParkC-G, et al. (2006) Simple procedures for the construction of a robust and cost-effective cell-free protein synthesis system. J Biotechnol 126: 554–561.

63. LiuJ, NurseP, MariansKJ (1996) The ordered assembly of the φX174-type primosome. J Biol Chem 271: 15656–15661.

64. RangarajanS, WoodgateR, GoodmanMF (1999) A phenotype for enigmatic DNA polymerase II: A pivotal role for pol II in replication restart in UV-irradiated Escherichia coli. Proc Natl Acad Sci U S A 96: 9224–9229.

65. SoreqH, LittauerUZ (1977) Purification and characterization of polynucleotide phosphorylase from Escherichia coli. Probe for the analysis of 3′ sequences of RNA. J Biol Chem 252: 6885–6888.

66. Bermúdez-CruzRM, García-MenaJ, MontañezC (2002) Polynucleotide phosphorylase binds to ssRNA with same affinity as to ssDNA. Biochimie 84: 321–328.

67. WolfT, JanzenW, BlumC, SchnetzK (2006) Differential dependence of StpA on H-NS in autoregulation of stpA and in regulation of bgl. J Bacteriol 188: 6728–6738.

68. GrossbergerR, MayerO, WaldsichC, SemradK, UrschitzS, et al. (2005) Influence of RNA structural stability on the RNA chaperone activity of the Escherichia coli protein StpA. Nucleic Acids Res 33: 2280–2289.

69. LuM, CampbellJL, BoyeE, KlecknerN (1994) SeqA: a negative modulator of replication initiation in E. coli. Cell 77: 413–426.

70. OkazakiR, ArisawaM, SuginoA (1971) Slow joining of newly replicated DNA chains in DNA polymerase I-deficient Escherichia coli mutants. Proc Natl Acad Sci U S A 68: 2954–2957.

71. KonradEB, LehmanIR (1974) A conditional lethal mutant of Escherichia coli K12 defective in the 5′→3′ exonuclease associated with DNA polymerase I. Proc Natl Acad Sci U S A 71: 2048–2051.

72. SandlerSJ, MariansKJ, ZavitzKH, CoutuJ, ParentMA, et al. (1999) dnaC mutations suppress defects in DNA replication- and recombination-associated functions in priB and priC double mutants in Escherichia coli K-12. Mol Microbiol 34: 91–101.

73. Makowska-GrzyskaM, KaguniJM (2010) Primase directs the release of DnaC from DnaB. Mol Cell 37: 90–101.

74. HellerRC, MariansKJ (2005) Unwinding of the nascent lagging strand by Rep and PriA enables the direct restart of stalled replication forks. J Biol Chem 280: 34143–34151.

75. MastroianniM, WatanabeK, WhiteTB, ZhuangF, VernonJ, et al. (2008) Group II intron-based gene targeting reactions in eukaryotes. PLoS ONE 3: e3121 doi:10.1371/journal.pone.0003121.

76. GoodierJL, ZhangL, VetterMR, KazazianHH (2007) LINE-1 ORF1 protein localizes in stress granules with other RNA-binding proteins, including components of RNA interference RNA-induced silencing complex. Mol Cell Biol 27: 6469–6483.

77. DoucetAJ, HulmeAE, SahinovicE, KulpaDA, MoldovanJB, et al. (2010) Characterization of LINE-1 ribonucleoprotein particles. PLoS Genet 6: e1001150 doi:10.1371/journal.pgen.1001150.

78. IchiyanagiK, BeauregardA, LawrenceS, SmithD, CousineauB, et al. (2002) Retrotransposition of the Ll.LtrB group II intron proceeds predominantly via reverse splicing into DNA targets. Mol Microbiol 46: 1259–1272.

79. Martínez-AbarcaF, Barrientos-DuránA, Fernández-LópezM, ToroN (2004) The RmInt1 group II intron has two different retrohoming pathways for mobility using predominantly the nascent lagging strand at DNA replication forks for priming. Nucleic Acids Res 32: 2880–2888.

80. ZhongJ, LambowitzAM (2003) Group II intron mobility using nascent strands at DNA replication forks to prime reverse transcription. EMBO J 22: 4555–4565.

81. KuboS, SelemeMdC, SoiferHS, PerezJLG, MoranJV, et al. (2006) L1 retrotransposition in nondividing and primary human somatic cells. Proc Natl Acad Sci U S A 103: 8036–8041.

82. JangS, SandlerSJ, HarsheyRM (2012) Mu insertions are repaired by the double-strand break repair pathway of Escherichia coli. PLoS Genet 8: e1002642 doi:10.1371/journal.pgen.1002642.

83. ZhaoJ, NiuW, YaoJ, MohrS, MarcotteEM, et al. (2008) Group II intron protein localization and insertion sites are affected by polyphosphate. PLoS Biol 6: e150 doi:10.1371/journal.pbio.0060150.

84. LongJE, MassoniSC, SandlerSJ (2010) RecA4142 causes SOS constitutive expression by loading onto reversed replication forks in Escherichia coli K-12. J Bacteriol 192: 2575–2582.

85. MuellerHJ, HintonJ (1941) A protein-free medium for primary isolation of the Gonococcus and Meningococcus. Proc Soc Exp Biol Med 48: 330–333.

86. Davis LG, Dibner MD, Battey JF (1986) Basic methods in molecular biology. New York: Elsovier.

87. CrameriA, WhitehornEA, TateE, StemmerWPC (1996) Improved green fluorescent protein by molecular evolution using DNA shuffling. Nat Biotechnol 14: 315–319.

88. ReinerAM (1969) Isolation and mapping of polynucleotide phosphorylase mutants of Escherichia coli. J Bacteriol 97: 1431–1436.

Štítky
Genetika Reprodukčná medicína

Článok vyšiel v časopise

PLOS Genetics


2013 Číslo 4
Najčítanejšie tento týždeň
Najčítanejšie v tomto čísle
Kurzy

Zvýšte si kvalifikáciu online z pohodlia domova

Eozinofilní granulomatóza s polyangiitidou
nový kurz
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#