An Apicoplast Localized Ubiquitylation System Is Required for the Import of Nuclear-encoded Plastid Proteins

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Apicomplexan parasites are responsible for numerous important human diseases including toxoplasmosis, cryptosporidiosis, and most importantly malaria. There is a constant need for new antimalarials, and one of most keenly pursued drug targets is an ancient algal endosymbiont, the apicoplast. The apicoplast is essential for parasite survival, and several aspects of its metabolism and maintenance have been validated as targets of anti-parasitic drug treatment. Most apicoplast proteins are nuclear encoded and have to be imported into the organelle. Recently, a protein translocon typically required for endoplasmic reticulum associated protein degradation (ERAD) has been proposed to act in apicoplast protein import. Here, we show ubiquitylation to be a conserved and essential component of this process. We identify apicoplast localized ubiquitin activating, conjugating and ligating enzymes in Toxoplasma gondii and Plasmodium falciparum and observe biochemical activity by in vitro reconstitution. Using conditional gene ablation and complementation analysis we link this activity to apicoplast protein import and parasite survival. Our studies suggest ubiquitylation to be a mechanistic requirement of apicoplast protein import independent to the proteasomal degradation pathway.

Vyšlo v časopise: An Apicoplast Localized Ubiquitylation System Is Required for the Import of Nuclear-encoded Plastid Proteins. PLoS Pathog 9(6): e32767. doi:10.1371/journal.ppat.1003426
Kategorie: Research Article
prolekare.web.journal.doi_sk: https://doi.org/10.1371/journal.ppat.1003426

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Zdroje

1. KohlerS, DelwicheCF, DennyPW, TilneyLG, WebsterP, et al. (1997) A plastid of probable green algal origin in Apicomplexan parasites. Science 275: 1485–1489.

2. GouldSB, WallerRF, McFaddenGI (2008) Plastid evolution. Annual review of plant biology 59: 491–517.

3. SeeberF, Soldati-FavreD (2010) Metabolic pathways in the apicoplast of apicomplexa. International review of cell and molecular biology 281: 161–228.

4. WallerRF, KeelingPJ, DonaldRG, StriepenB, HandmanE, et al. (1998) Nuclear-encoded proteins target to the plastid in Toxoplasma gondii and Plasmodium falciparum. Proceedings of the National Academy of Sciences of the United States of America 95: 12352–12357.

5. AgrawalS, StriepenB (2010) More membranes, more proteins: complex protein import mechanisms into secondary plastids. Protist 161: 672–687.

6. van DoorenGG, TomovaC, AgrawalS, HumbelBM, StriepenB (2008) Toxoplasma gondii Tic20 is essential for apicoplast protein import. Proceedings of the National Academy of Sciences of the United States of America 105: 13574–13579.

7. KalanonM, TonkinCJ, McFaddenGI (2009) Characterization of two putative protein translocation components in the apicoplast of Plasmodium falciparum. Eukaryotic cell 8: 1146–1154.

8. BullmannL, HaarmannR, MirusO, BredemeierR, HempelF, et al. (2010) Filling the gap, evolutionarily conserved Omp85 in plastids of chromalveolates. The Journal of biological chemistry 285: 6848–6856.

9. GlaserS, van DoorenGG, AgrawalS, BrooksCF, McFaddenGI, et al. (2012) Tic22 is an essential chaperone required for protein import into the apicoplast. The Journal of biological chemistry 287: 39505–39512.

10. SommerMS, GouldSB, LehmannP, GruberA, PrzyborskiJM, et al. (2007) Der1-mediated preprotein import into the periplastid compartment of chromalveolates? Molecular biology and evolution 24: 918–928.

11. SmithMH, PloeghHL, WeissmanJS (2011) Road to ruin: targeting proteins for degradation in the endoplasmic reticulum. Science 334: 1086–1090.

12. SporkS, HissJA, MandelK, SommerM, KooijTW, et al. (2009) An unusual ERAD-like complex is targeted to the apicoplast of Plasmodium falciparum. Eukaryotic cell 8: 1134–1145.

13. PontsN, YangJ, ChungDW, PrudhommeJ, GirkeT, et al. (2008) Deciphering the ubiquitin-mediated pathway in apicomplexan parasites: a potential strategy to interfere with parasite virulence. PloS one 3: e2386.

14. HempelF, BullmannL, LauJ, ZaunerS, MaierUG (2009) ERAD-derived preprotein transport across the second outermost plastid membrane of diatoms. Molecular biology and evolution 26: 1781–1790.

15. AgrawalS, van DoorenGG, BeattyWL, StriepenB (2009) Genetic evidence that an endosymbiont-derived endoplasmic reticulum-associated protein degradation (ERAD) system functions in import of apicoplast proteins. The Journal of biological chemistry 284: 33683–33691.

16. PickartCM, FushmanD (2004) Polyubiquitin chains: polymeric protein signals. Current opinion in chemical biology 8: 610–616.

17. LaneyJD, HochstrasserM (1999) Substrate targeting in the ubiquitin system. Cell 97: 427–430.

18. HempelF, FelsnerG, MaierUG (2010) New mechanistic insights into pre-protein transport across the second outermost plastid membrane of diatoms. Molecular microbiology 76: 793–801.

19. StorkS, MoogD, PrzyborskiJM, WilhelmiI, ZaunerS, et al. (2012) Distribution of the SELMA translocon in secondary plastids of red algal origin and predicted uncoupling of ubiquitin-dependent translocation from degradation. Eukaryotic cell 11: 1472–1481.

20. MacgurnJA, HsuPC, EmrSD (2012) Ubiquitin and membrane protein turnover: from cradle to grave. Annual review of biochemistry 81: 231–259.

21. YeY, MeyerHH, RapoportTA (2003) Function of the p97-Ufd1-Npl4 complex in retrotranslocation from the ER to the cytosol: dual recognition of nonubiquitinated polypeptide segments and polyubiquitin chains. The Journal of cell biology 162: 71–84.

22. ErnstR, ClaessenJH, MuellerB, SanyalS, SpoonerE, et al. (2011) Enzymatic blockade of the ubiquitin-proteasome pathway. PLoS biology 8: e1000605.

23. SheinerL, DemerlyJL, PoulsenN, BeattyWL, LucasO, et al. (2011) A systematic screen to discover and analyze apicoplast proteins identifies a conserved and essential protein import factor. PLoS pathogens 7: e1002392.

24. ChengMC, HsiehEJ, ChenJH, ChenHY, LinTP (2012) Arabidopsis RGLG2, functioning as a RING E3 ligase, interacts with AtERF53 and negatively regulates the plant drought stress response. Plant physiology 158: 363–375.

25. PetroskiMD, ZhouX, DongG, Daniel-IssakaniS, PayanDG, et al. (2007) Substrate modification with lysine 63-linked ubiquitin chains through the UBC13-UEV1A ubiquitin-conjugating enzyme. The Journal of biological chemistry 282: 29936–29945.

26. VesterlundM, ZadjaliF, PerssonT, NielsenML, KesslerBM, et al. (2011) The SOCS2 ubiquitin ligase complex regulates growth hormone receptor levels. PloS one 6: e25358.

27. MerckxA, Le RochK, NivezMP, DorinD, AlanoP, et al. (2003) Identification and initial characterization of three novel cyclin-related proteins of the human malaria parasite Plasmodium falciparum. The Journal of biological chemistry 278: 39839–39850.

28. DeRocherA, GilbertB, FeaginJE, ParsonsM (2005) Dissection of brefeldin A-sensitive and -insensitive steps in apicoplast protein targeting. J Cell Sci 118: 565–574.

29. StriepenB, CrawfordMJ, ShawMK, TilneyLG, SeeberF, et al. (2000) The plastid of Toxoplasma gondii is divided by association with the centrosomes. The Journal of cell biology 151: 1423–1434.

30. DonaldRG, RoosDS (1995) Insertional mutagenesis and marker rescue in a protozoan parasite: cloning of the uracil phosphoribosyltransferase locus from Toxoplasma gondii. Proceedings of the National Academy of Sciences of the United States of America 92: 5749–5753.

31. CookWJ, JeffreyLC, XuY, ChauV (1993) Tertiary structures of class I ubiquitin-conjugating enzymes are highly conserved: crystal structure of yeast Ubc4. Biochemistry 32: 13809–13817.

32. HaasAL, SiepmannTJ (1997) Pathways of ubiquitin conjugation. FASEB journal : official publication of the Federation of American Societies for Experimental Biology 11: 1257–1268.

33. CookBW, ShawGS (2012) Architecture of the catalytic HPN motif is conserved in all E2 conjugating enzymes. The Biochemical journal 445: 167–174.

34. WuPY, HanlonM, EddinsM, TsuiC, RogersRS, et al. (2003) A conserved catalytic residue in the ubiquitin-conjugating enzyme family. The EMBO journal 22: 5241–5250.

35. GallagherJR, MatthewsKA, PriggeST (2011) Plasmodium falciparum apicoplast transit peptides are unstructured in vitro and during apicoplast import. Traffic 12: 1124–1138.

36. LingQ, HuangW, BaldwinA, JarvisP (2012) Chloroplast biogenesis is regulated by direct action of the ubiquitin-proteasome system. Science 338: 655–659.

37. KarnatakiA, DeRocherAE, FeaginJE, ParsonsM (2009) Sequential processing of the Toxoplasma apicoplast membrane protein FtsH1 in topologically distinct domains during intracellular trafficking. Mol Biochem Parasitol 166: 126–133.

38. SchulzeA, StanderaS, BuergerE, KikkertM, van VoordenS, et al. (2005) The ubiquitin-domain protein HERP forms a complex with components of the endoplasmic reticulum associated degradation pathway. Journal of molecular biology 354: 1021–1027.

39. KnyM, StanderaS, Hartmann-PetersenR, KloetzelPM, SeegerM (2011) Herp regulates Hrd1-mediated ubiquitylation in a ubiquitin-like domain-dependent manner. The Journal of biological chemistry 286: 5151–5156.

40. HoellerD, DikicI (2009) Targeting the ubiquitin system in cancer therapy. Nature 458: 438–444.

41. Le RochKG, ZhouY, BlairPL, GraingerM, MochJK, et al. (2003) Discovery of gene function by expression profiling of the malaria parasite life cycle. Science 301: 1503–1508.

42. MazumdarJ, EHW, MasekK, CAH, StriepenB (2006) Apicoplast fatty acid synthesis is essential for organelle biogenesis and parasite survival in Toxoplasma gondii. Proceedings of the National Academy of Sciences of the United States of America 103: 13192–13197.

43. CrawfordMJ, Thomsen-ZiegerN, RayM, SchachtnerJ, RoosDS, et al. (2006) Toxoplasma gondii scavenges host-derived lipoic acid despite its de novo synthesis in the apicoplast. The EMBO journal 25: 3214–3222.