Discussion Mutations in the protein DJ-1 are associated with a recessive form of early onset PD. Although such mutations are relatively rare as a cause of PD ( Pankratz et al. 2006), they nevertheless provide an opportunity to uncover pathways that are involved in the etiology of this syndrome. To do so, it is imperative to elucidate the relevant normal functions of DJ-1, which of these normal functions are disrupted in PD, and how this disruption is caused. For PD-linked DJ-1 mutations that lead to changes in the amino acid sequence of the intact protein, functional effects are likely to be fundamentally mediated by associated changes in the physicochemical properties of the mutant proteins. To help determine the nature and extent of such changes, we studied the effects of five known PD-linked mutations on the structure and stability of DJ-1. In general, mutations can interfere with protein function through a variety of mechanisms. At one extreme, mutations can lead to global destabilization and unfolding of a protein, which is usually associated with complete loss of function, at least for proteins that require a well-folded conformation to carry out their biological activities. At the other extreme, mutations can lead to subtle changes on a protein's surface that can modulate its interactions with binding partners in ways that compromise its function without perturbing its structure. Intermediate effects are also possible, where the conformation of a protein can be locally (or globally) altered in ways that do not lead to complete global unfolding but nevertheless perturb structural (or dynamic) properties that are crucial for function. Our results indicate that the known PD-linked DJ-1 mutations cover the entire range of potential effects on the structure of the protein. At one extreme, the E64D DJ-1 mutation leaves the structure of the protein essentially unperturbed and appears to alter only the immediate vicinity of the mutated side chain, which is located at an exposed position on the protein surface. This is indicated by the lack of changes in the CD spectrum and melting curve of the protein ( Figs. 4, 5), combined with the very limited extent of chemical shift perturbations that are observed in two-dimensional NMR spectra of this mutant ( Figs. 6, 7). These results are entirely consistent with the previously determined crystal structure of this mutant, which shows no significant changes compared with the structure of the wild-type protein ( Hering et al. 2004). At the other extreme, the L166P mutation leads to a severe destabilization and global unfolding of DJ-1. The CD data, in agreement with previous reports ( Olzmann et al. 2004; Shendelman et al. 2004), indicate a dramatic disruption in secondary structure content, and the two-dimensional NMR spectrum of this mutant is clearly indicative of a highly disordered and flexible polypeptide chain ( Fig. 2, right panel). Although this severe destabilization of the L166P leads to an increased rate of degradation in vivo ( Macedo et al. 2003; Gorner et al. 2004; Olzmann et al. 2004), the degree of structural perturbation implied by our NMR spectra of L166P DJ-1 make it clear that the primary cause of the loss of function associated with this mutant is the loss of the protein's native structure and that the rapid degradation of the protein in vivo is a secondary effect. The structural effects of the other three PD-linked DJ-1 mutants are intermediate between the extremes delineated by the E64D and L166P mutations. Unlike the L166P mutation, none of these mutations disrupt the global fold of DJ-1. First, the CD spectra of all three mutants are similar in shape to that of the wild-type protein and clearly reflect the presence of well-formed elements of secondary structure. Furthermore, the two-dimensional NMR spectra of all three of these mutants ( Fig. 6) are very similar to that of the wild-type protein and contain a large number of resonances that precisely overlap the location of corresponding resonances in the spectrum of the wild-type protein. Because of the exquisite sensitivity of NMR chemical shifts to changes in the local environment of the originating nuclei, the observed degree of similarity between the wild-type and mutant spectra is a highly reliable indication that the overall fold of the proteins is the same and is not globally perturbed. In addition, this same argument implies that all three of these mutants are dimers in solution and dimerize through the same interface observed in the crystal structure of the wild-type protein. If the mutations led to the disruption of the DJ-1 dimer, even without further perturbation of the monomer structure, residues at the dimer interface would experience a profound change in their local environment and would be expected to exhibit significant chemical shift changes. No such changes are observed for any of the mutants for resonances originating from the dimer interface ( Figs. 7, 8). The conclusion that the M26I, A104T, and D149A mutants are all dimeric is consistent with previously reported pulldown assays that showed that each of these mutants is able to form both homodimers as well as heterodimers with the wild-type protein ( Blackinton et al. 2005). Given that the global structure of DJ-1 remains intact for the M26I, A104T, and D149A mutants, the decrease in secondary structure indicated in the CD spectra of the three mutants implies either that these mutations cause local perturbations of secondary structure within the protein, or possibly that they lead to a decrease in the thermodynamic stability of the protein such that the decreased CD signal reflects an equilibrium between well-folded and unfolded forms of the protein. Indeed, our CD melts demonstrate that each of the three proteins has a thermal melting temperature that is decreased by ~8°C relative to that of the wild-type protein. Nevertheless, the melting temperature of the mutants (69°C) remains far above the temperatures at which the CD and NMR spectra were acquired (27°C), and at the latter temperature, it is not expected that an appreciable fraction of unfolded protein would exist at equilibrium. In addition, if a significant population of unfolded protein existed at the conditions used for the CD and NMR experiments, this population should have been detectable as a second distinct set of signals in the NMR spectra, with dispersion properties similar to those observed for the highly unfolded L166P mutant. Since no such signals were observed in the NMR spectra, even at low contour levels (data not shown), it appears that at the temperature used here, all three of these mutants retain sufficient stability to remain well-folded. Therefore, it can be argued that the decrease in secondary structure observed in the CD spectra of all three mutants is likely caused by structural perturbations within the folded protein. Consistent with this conclusion, all three of these mutants give rise to chemical shift changes that propagate beyond residues in the immediate proximity of the site of mutation in the protein sequence, but do not indicate global unfolding. Our knowledge of the high-resolution structure of wild-type DJ-1 allows us to identify the structural elements that are most likely perturbed by each of the mutations by mapping the locations associated with chemical shift changes onto the structure. Figure 8 shows such a mapping for each of the three mutants. In the case of the M26I mutation, which occurs in α-helix 1, residues whose associated chemical shifts are most strongly affected are found at the C-terminal end of α-helix 1 and the linker from this helix to β-strand 2, at the N-terminal ends of β-strands 1, 2, and 6, which form part of a six-stranded parallel β-sheet, in the kink between α-helices 7 and 8, and also in the middle of α-helix 8. Thus, the decrease in secondary structure associated with this mutant might be expected to result from a fraying of the C terminus of α-helix 1 and the N-terminal regions of the three affected β-strands, as well as an alteration in the C-terminal region of α-helix 7 and a part of helix 8. The A104T mutation is found in β-strand 7 of the wild-type structure, near its C-terminal end. Chemical shift changes caused by this mutation are associated with residues in the C-terminal ends of adjacent β-strands 6, 7, and 11 of the six-stranded sheet; at the N termini of α-helices 3 and 5, which immediately follow strands 6 and 7, respectively; at the N terminus of α-helix 6; and in the middle of α-helix 7. A perturbation is also present at the C terminus of β-strand 2. In this case, perturbations localized predominantly to one half of the six-stranded β-sheet and fraying at the nearby N termini of three α-helices are expected to account for the changes observed in the CD spectrum of this mutant, although somewhat more distant residues (in strand 2 and helix 7) may be affected as well. Residue D149 is located at the C terminus of β-strand 10, which can be considered to be either the third strand in a three-stranded antiparallel β-sheet that abuts the larger six-stranded parallel sheet ( Wilson et al. 2003), or a seventh antiparallel strand at the end of the latter sheet ( Tao and Tong 2003). Alteration of this residue to alanine leads to shifts in resonances originating from the two other strands in the three-stranded sheet (β-strands 8 and 9) as well as in strands 11 and 7, located at the adjacent end of the parallel sheet. The loops between α-helix 6 and β-strand 8 and between β-strands 10 and 11 are also affected. The fact that this mutation leads to perturbations in two different β-sheets may account for the slightly greater decrease in secondary structure that is indicated by the CD spectrum of this mutant, although unlike what is observed for the other mutations, in this case there are no chemical shift perturbations associated with any elements of α-helical structure. Because there are few reported studies of the properties of the M26I, A104T, and D149A DJ-1 mutants, there is little context in which to interpret our results. All three mutants were shown to exhibit increased rates of turnover in cells ( Blackinton et al. 2005), consistent with both the structural and thermodynamic destabilization that we have documented here, but the M26I turnover rate was significantly higher than for A104T and D149A, although not as high as for the L166P mutant. For the M26I mutant, a recent report also indicated a decreased level of secondary structure as seen by CD, in agreement with our own results ( Hulleman et al. 2007). This study also showed, using size exclusion chromatography, that M26I is capable of forming dimers. Although the authors did not observe any heat denaturation of the M26I mutant by CD, in contrast with our own results, they did establish that this mutant is thermodynamically destabilized using chemical denaturant melts. The same study also noted that the M26I mutant has a higher propensity to oligomerize than the wild-type protein. In agreement with this result, we did observe that our M26I NMR samples were unstable over a timescale of several days, with the formation of a visible precipitate accompanying significant degradation in spectral quality. With regard to the A104T or D149A DJ-1 mutations, prior to our own work reported here, no such information has been reported. For all three of these “intermediate” mutations, no functional studies have been reported. Despite the absence of specific information about functional changes caused by the M26I, A104T, and D149A mutations, our results can be combined with what is known about the functions of wild-type DJ-1 to propose how these mutations might inactivate such functions. Both the chaperone and antioxidant proposed functions of DJ-1 appear to depend on oxidation/reduction of Cys 106 of the protein. Cys 106 is located just C-terminal to the end of β-strand 7, in close proximity to the antiparallel three-stranded sheet, the N termini of helices 6 and 7, and the C termini of β-strands 6, 7, and 11 of the six-stranded sheet. These structural elements are precisely the ones affected by the A104T and D149A mutations, as discussed above, and we therefore conjecture that these mutations compromise DJ-1 function by locally perturbing the protein geometry surrounding Cys 106 in such a way as to interfere with proper involvement of this residue in the function of the protein. In contrast, the M26I mutation affects structural elements that are relatively distant from Cys 106, and such a mechanism is less likely to be the basis of DJ-1 inactivation by this mutation. Instead, we propose that in the case of M26I, a perturbation of structure in α-helix 1, which is a central feature of the DJ-1 dimer interface, disrupts the contacts at this interface and leads to the previously noted decrease in the stability of the dimer ( Hulleman et al. 2007). This decreased dimer stability is, in turn, likely responsible both for the aggregation/precipitation observed by ourselves and Hulleman et al. (2007) as well as for the greatly increased turnover time of this mutant in cells relative to all other mutants save the highly unfolded L166P variant. Thus, the M26I mutant can form dimers, which based on the lack of structural perturbation near Cys 106 may be functional, but the instability of these dimers leads to aggregation and/or clearance of the protein, which we then propose is the fundamental cause of the loss of function of this DJ-1 mutant. While the work presented here was under review, an article appeared describing the crystal structures of the M26I and A104T DJ-1 mutants ( Lakshminarasimhan et al. 2008). The results are largely consistent with those described here. In particular, both mutant proteins adopt dimeric structures in which the global fold of the wild-type protein is closely preserved, in agreement with our conclusions based on the NMR data. Furthermore, the sites observed to be most clearly perturbed in the crystal structures of the mutants correspond to the regions with the greatest chemical shift changes in the NMR spectra of the mutants. Specifically, the A104T crystal structure shows significant (~0.4 Å) displacements of residues L72 and L112, which are in those regions that show the greatest chemical shift deviations, aside from the site of the mutation itself ( Fig. 7). Notably, the position of residue T154 is also slightly perturbed, and this is clearly reflected in the chemical shift data as well. The M26I structure shows an even larger (~0.7 Å) displacement for residue I31, which falls into the region exhibiting the largest chemical shift changes observed for any of the well-folded mutants in our study. An analysis using the program PROCOMPARE (part of the PROCHECK program suite) ( Laskowski et al. 1993) shows additional changes in the backbone dihedral angles of residues 32 and 33, consistent with large chemical shift changes at these sites, as well as smaller dihedral angle changes for residues 4 and 5, in accordance with smaller chemical shift deviations in this region. For both mutants, the chemical shift data delineate smaller changes at a number of other sites that are not obviously perturbed in the crystal structures. This likely reflects the exquisite sensitivity of chemical shifts to local environment and their ability to reflect changes that may be difficult to discern in crystal structures, even at high resolution. One significant difference between our results and those obtained based on the recent crystal structures is in the secondary structure content of the M26I and A104T mutants. In contrast to the partial loss of secondary structure implied by our CD data, the secondary structure elements of both mutants are fully intact in the crystal structures and are essentially identical to those of the wild-type protein. Although it is possible that partial oxidation of Cys 106 in our samples, as reported in prior studies ( Hulleman et al. 2007), might be responsible for this difference, this would be expected to give rise to chemical shift changes around Cys 106 and we do not observe such changes for the M26I mutant in particular ( Fig. 7). Alternate possible explanations for this disagreement may include the potentially stabilizing effects of crystal lattice packing or differences in the conditions used in the two studies. |
References Abou-Sleiman, P.M., Healy, D.G., Quinn, N., Lees, A.J., Wood, N.W. The role of pathogenic DJ-1 mutations in Parkinson's disease. Ann. Neurol. 2003;54:283–286. [PubMed]Andres-Mateos, E., Perier, C., Zhang, L., Blanchard-Fillion, B., Greco, T.M., Thomas, B., Ko, H.S., Sasaki, M., Ischiropoulos, H., Przedborski, S., et al. DJ-1 gene deletion reveals that DJ-1 is an atypical peroxiredoxin-like peroxidase. Proc. Natl. Acad. Sci. 2007;104:14807–14812. [PubMed]Annesi, G., Savettieri, G., Pugliese, P., D'Amelio, M., Tarantino, P., Ragonese, P., La Bella, V., Piccoli, T., Civitelli, D., Annesi, F., et al. DJ-1 mutations and parkinsonism-dementia-amyotrophic lateral sclerosis complex. Ann. Neurol. 2005;58:803–807. [PubMed]Betarbet, R., Canet-Aviles, R.M., Sherer, T.B., Mastroberardino, P.G., McLendon, C., Kim, J.H., Lund, S., Na, H.M., Taylor, G., Bence, N.F., et al. Intersecting pathways to neurodegeneration in Parkinson's disease: Effects of the pesticide rotenone on DJ-1, α-synuclein, and the ubiquitin-proteasome system. Neurobiol. Dis. 2006;22:404–420. [PubMed]Blackinton, J., Ahmad, R., Miller, D.W., van der Brug, M.P., Canet-Aviles, R.M., Hague, S.M., Kaleem, M., Cookson, M.R. Effects of DJ-1 mutations and polymorphisms on protein stability and subcellular localization. Brain Res. Mol. Brain Res. 2005;134:76–83. [PubMed]Bonifati, V., Rizzu, P., van Baren, M.J., Schaap, O., Breedveld, G.J., Krieger, E., Dekker, M.C., Squitieri, F., Ibanez, P., Joosse, M., et al. Mutations in the DJ-1 gene associated with autosomal recessive early-onset parkinsonism. Science. 2003;299:256–259. [PubMed]Canet-Aviles, R.M., Wilson, M.A., Miller, D.W., Ahmad, R., McLendon, C., Bandyopadhyay, S., Baptista, M.J., Ringe, D., Petsko, G.A., Cookson, M.R. The Parkinson's disease protein DJ-1 is neuroprotective due to cysteine-sulfinic acid-driven mitochondrial localization. Proc. Natl. Acad. Sci. 2004;101:9103–9108. [PubMed]Delaglio, F., Grzesiek, S., Vuister, G.W., Zhu, G., Pfeifer, J., Bax, A. NMRPipe: A multidimensional spectral processing system based on UNIX pipes. J. Biomol. NMR. 1995;6:277–293. [PubMed]Gorner, K., Holtorf, E., Odoy, S., Nuscher, B., Yamamoto, A., Regula, J.T., Beyer, K., Haass, C., Kahle, P.J. Differential effects of Parkinson's disease-associated mutations on stability and folding of DJ-1. J. Biol. Chem. 2004;279:6943–6951. [PubMed]Grzesiek, S., Bax, A., Clore, G.M., Gronenborn, A.M., Hu, J.S., Kaufman, J., Palmer, I., Stahl, S.J., Wingfield, P.T. The solution structure of HIV-1 Nef reveals an unexpected fold and permits delineation of the binding surface for the SH3 domain of Hck tyrosine protein kinase. Nat. Struct. Biol. 1996;3:340–345. [PubMed]Hague, S., Rogaeva, E., Hernandez, D., Gulick, C., Singleton, A., Hanson, M., Johnson, J., Weiser, R., Gallardo, M., Ravina, B., et al. Early-onset Parkinson's disease caused by a compound heterozygous DJ-1 mutation. Ann. Neurol. 2003;54:271–274. [PubMed]Hering, R., Strauss, K.M., Tao, X., Bauer, A., Woitalla, D., Mietz, E.M., Petrovic, S., Bauer, P., Schaible, W., Muller, T., et al. Novel homozygous p.E64D mutation in DJ1 in early onset Parkinson disease (PARK7). Hum. Mutat. 2004;24:321–329. [PubMed]Hod, Y., Pentyala, S.N., Whyard, T.C., El-Maghrabi, M.R. Identification and characterization of a novel protein that regulates RNA-protein interaction. J. Cell. Biochem. 1999;72:435–444. [PubMed]Honbou, K., Suzuki, N.N., Horiuchi, M., Niki, T., Taira, T., Ariga, H., Inagaki, F. The crystal structure of DJ-1, a protein related to male fertility and Parkinson's disease. J. Biol. Chem. 2003;278:31380–31384. [PubMed]Huai, Q., Sun, Y., Wang, H., Chin, L.S., Li, L., Robinson, H., Ke, H. Crystal structure of DJ-1/RS and implication on familial Parkinson's disease. FEBS Lett. 2003;549:171–175. [PubMed]Hulleman, J.D., Mirzaei, H., Guigard, E., Taylor, K.L., Ray, S.S., Kay, C.M., Regnier, F.E., Rochet, J.C. Destabilization of DJ-1 by familial substitution and oxidative modifications: Implications for Parkinson's disease. Biochemistry. 2007;46:5776–5789. [PubMed]Johnson, B.A., Blevins, R.A. NMRView: A computer program for the visualization and analysis of NMR data. J. Biomol. NMR. 1994;4:603–614. Kabsch, W., Sander, C. Dictionary of protein secondary structure: Pattern recognition of hydrogen-bonded and geometrical features. Biopolymers. 1983;22:2577–2637. [PubMed]Kim, R.H., Smith, P.D., Aleyasin, H., Hayley, S., Mount, M.P., Pownall, S., Wakeham, A., You-Ten, A.J., Kalia, S.K., Horne, P., et al. Hypersensitivity of DJ-1-deficient mice to 1-methyl-4-phenyl-1,2,3,6-tetrahydropyrindine (MPTP) and oxidative stress. Proc. Natl. Acad. Sci. 2005;102:5215–5220. [PubMed]Kitada, T., Asakawa, S., Hattori, N., Matsumine, H., Yamamura, Y., Minoshima, S., Yokochi, M., Mizuno, Y., Shimizu, N. Mutations in the parkin gene cause autosomal recessive juvenile parkinsonism. Nature. 1998;392:605–608. [PubMed]Koradi, R., Billeter, M., Wuthrich, K. MOLMOL: A program for display and analysis of macromolecular structures. J. Mol. Graph. 1996;14:29–32. 51–55. Lakshminarasimhan, M., Maldonado, M.T., Zhou, W., Fink, A.L., Wilson, M.A. Structural impact of three Parkinsonism-associated missense mutations on human DJ-1. Biochemistry. 2008;47:1381–1392. [PubMed]Laskowski, R.A., MacArthur, M.W., Moss, D.S., Thornton, J.M. PROCHECK: A program to check the stereochemical quality of protein structures. J. Appl. Crystallogr. 1993;26:283–291. Lavara-Culebras, E., Paricio, N.
Drosophila DJ-1 mutants are sensitive to oxidative stress and show reduced lifespan and motor deficits. Gene. 2007;400:158–165. [PubMed]Lee, S.J., Kim, S.J., Kim, I.K., Ko, J., Jeong, C.S., Kim, G.H., Park, C., Kang, S.O., Suh, P.G., Lee, H.S., et al. Crystal structures of human DJ-1 and Escherichia coli Hsp31, which share an evolutionarily conserved domain. J. Biol. Chem. 2003;278:44552–44559. [PubMed]Macedo, M.G., Anar, B., Bronner, I.F., Cannella, M., Squitieri, F., Bonifati, V., Hoogeveen, A., Heutink, P., Rizzu, P. The DJ-1L166P mutant protein associated with early onset Parkinson's disease is unstable and forms higher-order protein complexes. Hum. Mol. Genet. 2003;12:2807–2816. [PubMed]Martinat, C., Shendelman, S., Jonason, A., Leete, T., Beal, M.F., Yang, L., Floss, T., Abeliovich, A. Sensitivity to oxidative stress in DJ-1-deficient dopamine neurons: An ES-derived cell model of primary Parkinsonism. PLoS Biol. 2004;2:e327. doi: 10.1371/journal.pbio.0020327. [PubMed]Miller, D.W., Ahmad, R., Hague, S., Baptista, M.J., Canet-Aviles, R., McLendon, C., Carter, D.M., Zhu, P.P., Stadler, J., Chandran, J., et al. L166P mutant DJ-1, causative for recessive Parkinson's disease, is degraded through the ubiquitin-proteasome system. J. Biol. Chem. 2003;278:36588–36595. [PubMed]Mitsumoto, A., Nakagawa, Y. DJ-1 is an indicator for endogenous reactive oxygen species elicited by endotoxin. Free Radic. Res. 2001;35:885–893. [PubMed]Mitsumoto, A., Nakagawa, Y., Takeuchi, A., Okawa, K., Iwamatsu, A., Takanezawa, Y. Oxidized forms of peroxiredoxins and DJ-1 on two-dimensional gels increased in response to sub-lethal levels of paraquat. Free Radic. Res. 2001;35:301–310. [PubMed]Moore, D.J., Zhang, L., Dawson, T.M., Dawson, V.L. A missense mutation (L166P) in DJ-1, linked to familial Parkinson's disease, confers reduced protein stability and impairs homo-oligomerization. J. Neurochem. 2003;87:1558–1567. [PubMed]Olzmann, J.A., Brown, K., Wilkinson, K.D., Rees, H.D., Huai, Q., Ke, H., Levey, A.I., Li, L., Chin, L.S. Familial Parkinson's disease-associated L166P mutation disrupts DJ-1 protein folding and function. J. Biol. Chem. 2004;279:8506–8515. [PubMed]Paisan-Ruiz, C., Jain, S., Evans, E.W., Gilks, W.P., Simon, J., van der Brug, M., Lopez de Munain, A., Aparicio, S., Gil, A.M., Khan, N., et al. Cloning of the gene containing mutations that cause PARK8-linked Parkinson's disease. Neuron. 2004;44:595–600. [PubMed]Pankratz, N., Pauciulo, M.W., Elsaesser, V.E., Marek, D.K., Halter, C.A., Wojcieszek, J., Rudolph, A., Shults, C.W., Foroud, T., Nichols, W.C. Mutations in DJ-1 are rare in familial Parkinson disease. Neurosci. Lett. 2006;408:209–213. [PubMed]Polymeropoulos, M.H., Lavedan, C., Leroy, E., Ide, S.E., Dehejia, A., Dutra, A., Pike, B., Root, H., Rubenstein, J., Boyer, R., et al. Mutation in the α-synuclein gene identified in families with Parkinson's disease. Science. 1997;276:2045–2047. [PubMed]Ramirez, A., Heimbach, A., Grundemann, J., Stiller, B., Hampshire, D., Cid, L.P., Goebel, I., Mubaidin, A.F., Wriekat, A.L., Roeper, J., et al. Hereditary parkinsonism with dementia is caused by mutations in ATP13A2, encoding a lysosomal type 5 P-type ATPase. Nat. Genet. 2006;38:1184–1191. [PubMed]Shendelman, S., Jonason, A., Martinat, C., Leete, T., Abeliovich, A. DJ-1 is a redox-dependent molecular chaperone that inhibits α-synuclein aggregate formation. PLoS Biol. 2004;2:e362. doi: 10.1371/journal.pbio.0020362. [PubMed]Taira, T., Saito, Y., Niki, T., Iguchi-Ariga, S.M., Takahashi, K., Ariga, H. DJ-1 has a role in antioxidative stress to prevent cell death. EMBO Rep. 2004;5:213–218. [PubMed]Tang, B., Xiong, H., Sun, P., Zhang, Y., Wang, D., Hu, Z., Zhu, Z., Ma, H., Pan, Q., Xia, J.H., et al. Association of PINK1 and DJ-1 confers digenic inheritance of early-onset Parkinson's disease. Hum. Mol. Genet. 2006;15:1816–1825. [PubMed]Tao, X., Tong, L. Crystal structure of human DJ-1, a protein associated with early onset Parkinson's disease. J. Biol. Chem. 2003;278:31372–31379. [PubMed]Valente, E.M., Abou-Sleiman, P.M., Caputo, V., Muqit, M.M., Harvey, K., Gispert, S., Ali, Z., Del Turco, D., Bentivoglio, A.R., Healy, D.G., et al. Hereditary early-onset Parkinson's disease caused by mutations in PINK1. Science. 2004;304:1158–1160. [PubMed]Wagenfeld, A., Gromoll, J., Cooper, T.G. Molecular cloning and expression of rat contraception associated protein 1 (CAP1), a protein putatively involved in fertilization. Biochem. Biophys. Res. Commun. 1998;251:545–549. [PubMed]Wilson, M.A., Collins, J.L., Hod, Y., Ringe, D., Petsko, G.A. The 1.1-Å resolution crystal structure of DJ-1, the protein mutated in autosomal recessive early onset Parkinson's disease. Proc. Natl. Acad. Sci. 2003;100:9256–9261. [PubMed]Wishart, D.S., Sykes, B.D. The 13C chemical-shift index: A simple method for the identification of protein secondary structure using 13C chemical-shift data. J. Biomol. NMR. 1994;4:171–180. [PubMed]Zhou, W., Zhu, M., Wilson, M.A., Petsko, G.A., Fink, A.L. The oxidation state of DJ-1 regulates its chaperone activity toward α-synuclein. J. Mol. Biol. 2006;356:1036–1048. [PubMed]Zimprich, A., Biskup, S., Leitner, P., Lichtner, P., Farrer, M., Lincoln, S., Kachergus, J., Hulihan, M., Uitti, R.J., Calne, D.B., et al. Mutations in LRRK2 cause autosomal-dominant parkinsonism with pleomorphic pathology. Neuron. 2004;44:601–607. [PubMed]
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