#PAGE_PARAMS# #ADS_HEAD_SCRIPTS# #MICRODATA#

Discovery of a Splicing Regulator Required for Cell Cycle Progression


In the G1 phase of the cell division cycle, eukaryotic cells prepare many of the resources necessary for a new round of growth including renewal of the transcriptional and protein synthetic capacities and building the machinery for chromosome replication. The function of G1 has an early evolutionary origin and is preserved in single and multicellular organisms, although the regulatory mechanisms conducting G1 specific functions are only understood in a few model eukaryotes. Here we describe a new G1 mutant from an ancient family of apicomplexan protozoans. Toxoplasma gondii temperature-sensitive mutant 12-109C6 conditionally arrests in the G1 phase due to a single point mutation in a novel protein containing a single RNA-recognition-motif (TgRRM1). The resulting tyrosine to asparagine amino acid change in TgRRM1 causes severe temperature instability that generates an effective null phenotype for this protein when the mutant is shifted to the restrictive temperature. Orthologs of TgRRM1 are widely conserved in diverse eukaryote lineages, and the human counterpart (RBM42) can functionally replace the missing Toxoplasma factor. Transcriptome studies demonstrate that gene expression is downregulated in the mutant at the restrictive temperature due to a severe defect in splicing that affects both cell cycle and constitutively expressed mRNAs. The interaction of TgRRM1 with factors of the tri-SNP complex (U4/U6 & U5 snRNPs) indicate this factor may be required to assemble an active spliceosome. Thus, the TgRRM1 family of proteins is an unrecognized and evolutionarily conserved class of splicing regulators. This study demonstrates investigations into diverse unicellular eukaryotes, like the Apicomplexa, have the potential to yield new insights into important mechanisms conserved across modern eukaryotic kingdoms.


Vyšlo v časopise: Discovery of a Splicing Regulator Required for Cell Cycle Progression. PLoS Genet 9(2): e32767. doi:10.1371/journal.pgen.1003305
Kategorie: Research Article
prolekare.web.journal.doi_sk: https://doi.org/10.1371/journal.pgen.1003305

Souhrn

In the G1 phase of the cell division cycle, eukaryotic cells prepare many of the resources necessary for a new round of growth including renewal of the transcriptional and protein synthetic capacities and building the machinery for chromosome replication. The function of G1 has an early evolutionary origin and is preserved in single and multicellular organisms, although the regulatory mechanisms conducting G1 specific functions are only understood in a few model eukaryotes. Here we describe a new G1 mutant from an ancient family of apicomplexan protozoans. Toxoplasma gondii temperature-sensitive mutant 12-109C6 conditionally arrests in the G1 phase due to a single point mutation in a novel protein containing a single RNA-recognition-motif (TgRRM1). The resulting tyrosine to asparagine amino acid change in TgRRM1 causes severe temperature instability that generates an effective null phenotype for this protein when the mutant is shifted to the restrictive temperature. Orthologs of TgRRM1 are widely conserved in diverse eukaryote lineages, and the human counterpart (RBM42) can functionally replace the missing Toxoplasma factor. Transcriptome studies demonstrate that gene expression is downregulated in the mutant at the restrictive temperature due to a severe defect in splicing that affects both cell cycle and constitutively expressed mRNAs. The interaction of TgRRM1 with factors of the tri-SNP complex (U4/U6 & U5 snRNPs) indicate this factor may be required to assemble an active spliceosome. Thus, the TgRRM1 family of proteins is an unrecognized and evolutionarily conserved class of splicing regulators. This study demonstrates investigations into diverse unicellular eukaryotes, like the Apicomplexa, have the potential to yield new insights into important mechanisms conserved across modern eukaryotic kingdoms.


Zdroje

1. GajadharAA, MarquardtWC, HallR, GundersonJ, Ariztia-CarmonaEV, et al. (1991) Ribosomal RNA sequences of Sarcocystis muris, Theileria annulata and Crypthecodinium cohnii reveal evolutionary relationships among apicomplexans, dinoflagellates, and ciliates. Molecular and biochemical parasitology 45: 147–154.

2. EscalanteAA, AyalaFJ (1995) Evolutionary origin of Plasmodium and other Apicomplexa based on rRNA genes. Proceedings of the National Academy of Sciences of the United States of America 92: 5793–5797.

3. RogozinIB, BasuMK, CsurosM, KooninEV (2009) Analysis of rare genomic changes does not support the unikont-bikont phylogeny and suggests cyanobacterial symbiosis as the point of primary radiation of eukaryotes. Genome Biol Evol 1: 99–113.

4. GethingPW, PatilAP, SmithDL, GuerraCA, ElyazarIR, et al. (2011) A new world malaria map: Plasmodium falciparum endemicity in 2010. Malar J 10: 378.

5. WongJT, KwokAC (2005) Proliferation of dinoflagellates: blooming or bleaching. Bioessays 27: 730–740.

6. GubbelsMJ, WhiteM, SzatanekT (2008) The cell cycle and Toxoplasma gondii cell division: tightly knit or loosely stitched? Int J Parasitol 38: 1343–1358.

7. StriepenB, JordanCN, ReiffS, van DoorenGG (2007) Building the perfect parasite: cell division in apicomplexa. PLoS Pathog 3: e78 doi:10.1371/journal.ppat.0030078

8. GubbelsMJ, LehmannM, MuthalagiM, JeromeME, BrooksCF, et al. (2008) Forward genetic analysis of the apicomplexan cell division cycle in Toxoplasma gondii. PLoS Pathog 4: e36 doi:10.1371/journal.ppat.0040036

9. CrossFR, BuchlerNE, SkotheimJM (2011) Evolution of networks and sequences in eukaryotic cell cycle control. Philos Trans R Soc Lond B Biol Sci 366: 3532–3544.

10. SuvorovaES, LehmannMM, KratzerS, WhiteMW (2012) Nuclear actin-related protein is required for chromosome segregation in Toxoplasma gondii. Molecular and biochemical parasitology 181: 7–16.

11. SzatanekT, Anderson-WhiteBR, Faugno-FusciDM, WhiteM, SaeijJP, et al. (2012) Cactin is essential for G1 progression in Toxoplasma gondii. Molecular microbiology 84: 566–577.

12. RadkeJR, StriepenB, GueriniMN, JeromeME, RoosDS, et al. (2001) Defining the cell cycle for the tachyzoite stage of Toxoplasma gondii. Mol Biochem Parasitol 115: 165–175.

13. BehnkeMS, WoottonJC, LehmannMM, RadkeJB, LucasO, et al. (2010) Coordinated progression through two subtranscriptomes underlies the tachyzoite cycle of Toxoplasma gondii. PLoS ONE 5: e12354 doi:10.1371/journal.pone.0012354

14. BozdechZ, LlinasM, PulliamBL, WongED, ZhuJ, et al. (2003) The transcriptome of the intraerythrocytic developmental cycle of Plasmodium falciparum. PLoS Biol 1: e5 doi:10.1371/journal.pbio.0000005

15. WhiteMW, JeromeME, VaishnavaS, GueriniM, BehnkeM, et al. (2005) Genetic rescue of a Toxoplasma gondii conditional cell cycle mutant. Molecular microbiology 55: 1060–1071.

16. RadkeJR, GueriniMN, WhiteMW (2000) Toxoplasma gondii: characterization of temperature-sensitive tachyzoite cell cycle mutants. Experimental parasitology 96: 168–177.

17. CleryA, BlatterM, AllainFH (2008) RNA recognition motifs: boring? Not quite. Current opinion in structural biology 18: 290–298.

18. MarisC, DominguezC, AllainFH (2005) The RNA recognition motif, a plastic RNA-binding platform to regulate post-transcriptional gene expression. The FEBS journal 272: 2118–2131.

19. NurseP, ThuriauxP, NasmythK (1976) Genetic control of the cell division cycle in the fission yeast Schizosaccharomyces pombe. Molecular & general genetics: MGG 146: 167–178.

20. HartwellLH (1967) Macromolecule synthesis in temperature-sensitive mutants of yeast. Journal of bacteriology 93: 1662–1670.

21. JuricaMS, MooreMJ (2003) Pre-mRNA splicing: awash in a sea of proteins. Molecular cell 12: 5–14.

22. RinoJ, Carmo-FonsecaM (2009) The spliceosome: a self-organized macromolecular machine in the nucleus? Trends in cell biology 19: 375–384.

23. WillCL, LuhrmannR (2011) Spliceosome structure and function. Cold Spring Harbor perspectives in biology 3.

24. HoskinsAA, MooreMJ (2012) The spliceosome: a flexible, reversible macromolecular machine. Trends in biochemical sciences 37: 179–188.

25. WahlMC, WillCL, LuhrmannR (2009) The spliceosome: design principles of a dynamic RNP machine. Cell 136: 701–718.

26. StanekD, NeugebauerKM (2006) The Cajal body: a meeting place for spliceosomal snRNPs in the nuclear maze. Chromosoma 115: 343–354.

27. SchneiderM, HsiaoHH, WillCL, GietR, UrlaubH, et al. (2010) Human PRP4 kinase is required for stable tri-snRNP association during spliceosomal B complex formation. Nature structural & molecular biology 17: 216–221.

28. SchwelnusW, RichertK, OpitzF, GrossT, HabaraY, et al. (2001) Fission yeast Prp4p kinase regulates pre-mRNA splicing by phosphorylating a non-SR-splicing factor. EMBO reports 2: 35–41.

29. OhiMD, LinkAJ, RenL, JenningsJL, McDonaldWH, et al. (2002) Proteomics analysis reveals stable multiprotein complexes in both fission and budding yeasts containing Myb-related Cdc5p/Cef1p, novel pre-mRNA splicing factors, and snRNAs. Molecular and cellular biology 22: 2011–2024.

30. Luz AmbrosioD, LeeJH, PanigrahiAK, NguyenTN, CicarelliRM, et al. (2009) Spliceosomal proteomics in Trypanosoma brucei reveal new RNA splicing factors. Eukaryotic cell 8: 990–1000.

31. RenL, McLeanJR, HazbunTR, FieldsS, Vander KooiC, et al. (2011) Systematic two-hybrid and comparative proteomic analyses reveal novel yeast pre-mRNA splicing factors connected to Prp19. PLoS ONE 6: e16719 doi:10.1371/journal.pone.0016719

32. HeroldN, WillCL, WolfE, KastnerB, UrlaubH, et al. (2009) Conservation of the protein composition and electron microscopy structure of Drosophila melanogaster and human spliceosomal complexes. Molecular and cellular biology 29: 281–301.

33. DeckertJ, HartmuthK, BoehringerD, BehzadniaN, WillCL, et al. (2006) Protein composition and electron microscopy structure of affinity-purified human spliceosomal B complexes isolated under physiological conditions. Molecular and cellular biology 26: 5528–5543.

34. CoteP, HoguesH, WhitewayM (2009) Transcriptional analysis of the Candida albicans cell cycle. Mol Biol Cell 20: 3363–3373.

35. SpellmanPT, SherlockG, ZhangMQ, IyerVR, AndersK, et al. (1998) Comprehensive identification of cell cycle-regulated genes of the yeast Saccharomyces cerevisiae by microarray hybridization. Mol Biol Cell 9: 3273–3297.

36. WhitfieldML, SherlockG, SaldanhaAJ, MurrayJI, BallCA, et al. (2002) Identification of genes periodically expressed in the human cell cycle and their expression in tumors. Mol Biol Cell 13: 1977–2000.

37. QuZ, WeissJN, MacLellanWR (2003) Regulation of the mammalian cell cycle: a model of the G1-to-S transition. Am J Physiol Cell Physiol 284: C349–364.

38. BahlerJ (2005) Cell-cycle control of gene expression in budding and fission yeast. Annu Rev Genet 39: 69–94.

39. FerreiraJA, Carmo-FonsecaM, LamondAI (1994) Differential interaction of splicing snRNPs with coiled bodies and interchromatin granules during mitosis and assembly of daughter cell nuclei. The Journal of cell biology 126: 11–23.

40. PrasanthKV, Sacco-BubulyaPA, PrasanthSG, SpectorDL (2003) Sequential entry of components of the gene expression machinery into daughter nuclei. Molecular biology of the cell 14: 1043–1057.

41. White MW, Conde de Felipe M, Lehmann M, Radke JR (2007) Cell cycle control and parasite division. ; Aijoka JW, Soldati D, editors. Norwich, UK: Horizon Scientific Press.

42. RoosDS, DonaldRG, MorrissetteNS, MoultonAL (1994) Molecular tools for genetic dissection of the protozoan parasite Toxoplasma gondii. Methods in cell biology 45: 27–63.

43. GajiRY, BehnkeMS, LehmannMM, WhiteMW, CarruthersVB (2011) Cell cycle-dependent, intercellular transmission of Toxoplasma gondii is accompanied by marked changes in parasite gene expression. Molecular microbiology 79: 192–204.

44. BrooksCF, FranciaME, GissotM, CrokenMM, KimK, et al. (2011) Toxoplasma gondii sequesters centromeres to a specific nuclear region throughout the cell cycle. Proceedings of the National Academy of Sciences of the United States of America 108: 3767–3772.

45. BaluB, MaherSP, PanceA, ChauhanC, NaumovAV, et al. (2011) CCR4-associated factor 1 coordinates the expression of Plasmodium falciparum egress and invasion proteins. Eukaryot Cell 10: 1257–1263.

46. Herm-GotzA, Agop-NersesianC, MunterS, GrimleyJS, WandlessTJ, et al. (2007) Rapid control of protein level in the apicomplexan Toxoplasma gondii. Nature methods 4: 1003–1005.

47. QuinlanAR, HallIM (2010) BEDTools: a flexible suite of utilities for comparing genomic features. Bioinformatics 26: 841–842.

48. MortazaviA, WilliamsBA, McCueK, SchaefferL, WoldB (2008) Mapping and quantifying mammalian transcriptomes by RNA-Seq. Nat Methods 5: 621–628.

49. HuK, MannT, StriepenB, BeckersCJ, RoosDS, et al. (2002) Daughter Cell Assembly in the Protozoan Parasite Toxoplasma gondii. Mol Biol Cell 13: 593–606.

50. BartfaiR, HoeijmakersWA, Salcedo-AmayaAM, SmitsAH, Janssen-MegensE, et al. (2010) H2A.Z demarcates intergenic regions of the plasmodium falciparum epigenome that are dynamically marked by H3K9ac and H3K4me3. PLoS Pathog 6: e1001223 doi: 10.1371/journal.ppat.1001223

51. ColeSE, LaRiviereFJ (2008) Chapter 12. Analysis of nonfunctional ribosomal RNA decay in Saccharomyces cerevisiae. Methods Enzymol 449: 239–259.

Štítky
Genetika Reprodukčná medicína

Článok vyšiel v časopise

PLOS Genetics


2013 Číslo 2
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#