The Detection and Quantitation of Protein Oligomerization

  • David A. Gell
  • Richard P. Grant
  • Joel P. Mackay
Part of the Advances in Experimental Medicine and Biology book series (AEMB, volume 747)

Abstract

There are many different techniques available to biologists and biochemists that can be used to detect and characterize the self-association of proteins. Each technique has strengths and weaknesses and it is often useful to combine several approaches to maximize the former and minimize the latter. Here we review a range of methodologies that identify protein self-association and/or allow the stoichiometry and affinity of the interaction to be determined, placing an emphasis on what type of information can be obtained and outlining the advantages and disadvantages involved. In general, in vitro biophysical techniques, such as size exclusion chromatography, analytical ultracentrifugation, scattering techniques, NMR spectroscopy, isothermal titration calorimetry, fluorescence anisotropy and mass spectrometry, provide information on stoichiometry and/or binding affinities. Other approaches such as cross-linking, fluorescence methods (e.g., fluorescence correlation spectroscopy, FCS; Förster resonance energy transfer, FRET; fluorescence recovery after photobleaching, FRAP; and proximity imaging, PRIM) and complementation approaches (e.g., yeast two hybrid assays and bimolecular fluorescence complementation, BiFC) can be used to detect protein self-association in a cellular context.

Keywords

Cholesterol Formaldehyde Migration Anisotropy Titration 

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References

  1. 1.
    Valdes R Jr, Ackers GK. Study of protein subunit association equilibria by elution gel chromatography. Methods Enzymol 1979; 61:125–142.PubMedCrossRefGoogle Scholar
  2. 2.
    Siegel LM, Monty KJ. Determination of molecular weights and frictional ratios of proteins in impure systems by use of gel filtration and density gradient centrifugation. Application to crude preparations of sulfite and hydroxylamine reductases. Biochim Biophys Acta 1966; 112:346–362.PubMedCrossRefGoogle Scholar
  3. 3.
    Cantor CR, Schimmel PR. Biophysical Chemistry. Vol Part II: Techniques for the study of biological structure and function. San Francisco: Freeman, 1980.Google Scholar
  4. 4.
    Andrews P. The gel-filtration behaviour of proteins related to their molecular weights over a wide range. Biochem J 1965; 96:595–606.PubMedGoogle Scholar
  5. 5.
    Stevens FJ, Schiffer M. Computer simulation of protein self-association during small-zone gel filtration. Estimation of equilibrium constants. Biochem J 1981; 195:213–219.PubMedGoogle Scholar
  6. 6.
    Stevens FJ. Analysis of protein-protein interaction by simulation of small-zone size-exclusion chromatography: application to an antibody-antigen association. Biochemistry 1986; 25:981–993.PubMedCrossRefGoogle Scholar
  7. 7.
    Ceschini S, Lupidi G, Coletta M et al. Multimeric self-assembly equilibria involving the histone-like protein H-NS. A thermodynamic study. J Biol Chem 2000; 275:729–734.PubMedCrossRefGoogle Scholar
  8. 8.
    Darling PJ, Holt JM, Ackers GK. Coupled energetics of lambda cro repressor self-assembly and site-specific DNA operator binding I: analysis of cro dimerization from nanomolar to micromolar concentrations. Biochemistry 2000; 39:11500–11507.PubMedCrossRefGoogle Scholar
  9. 9.
    del Alamo M, Neira JL, Mateu MG. Thermodynamic dissection of a low affinity protein-protein interface involved in human immunodeficiency virus assembly. J Biol Chem 2003; 278:27923–27929.PubMedCrossRefGoogle Scholar
  10. 10.
    van Holde KE, Johnson WC, Ho PS. Principles of Physical Biochemistry. 2 ed. Upper Saddle River: Prentice-Hall, 2006.Google Scholar
  11. 11.
    Laue TM, Bhairavi DS, Ridgeway TM et al. Computer-aided interpretation of analytical sedimentation data. In: Harding SE, Rowe AJ, Horton JC, eds. Analytical Ultracentrifugation in Biochemistry and Polymer Science. Cambridge: Royal Society of Chemistry, 1992:90–125.Google Scholar
  12. 12.
    Rowe AJ. The concentration dependence of sedimentation. In: Harding SE, Rowe AJ, Horton JC, eds. Analytical Ultracentrifugation in Biochemistry and Polymer Science. Cambridge: Royal Society of Chemistry, 1992.Google Scholar
  13. 13.
    Demeler B, Saber H, Hansen JC. Identification and interpretation of complexity in sedimentation velocity boundaries. Biophys J 1997; 72:397–407.PubMedCrossRefGoogle Scholar
  14. 14.
    Stafford WF. Sedimentation boundary analysis of interactiong systems: use of the apparent sedimentation coefficient distribution function. In: Shuster TM, Laue TM, eds. Modern Analytical Ultracentrifugation. Boston: Birkhauser, 1994:119–137.CrossRefGoogle Scholar
  15. 15.
    Cole JL. Characterization of human cytomegalovirus protease dimerization by analytical centrifugation. Biochemistry 1996; 35:15601–15610.PubMedCrossRefGoogle Scholar
  16. 16.
    Ali SA, Iwabuchi N, Matsui T et al. Reversible and fast association equilibria of a molecular chaperone, gp57A, of bacteriophage T4. Biophys J 2003; 85:2606–2618.PubMedCrossRefGoogle Scholar
  17. 17.
    Zhao H, Beckett D. Kinetic partitioning between alternative protein-protein interactions controls a transcriptional switch. J Mol Biol 2008; 380:223–236.PubMedCrossRefGoogle Scholar
  18. 18.
    Nan R, Gor J, Perkins SJ. Implications of the progressive self-association of wild-type human factor H for complement regulation and disease. J Mol Biol 2008; 375:891–900.PubMedCrossRefGoogle Scholar
  19. 19.
    Waxman E, Laws WR, Laue TM et al. Refining hydrodynamic shapes of proteins: the combination of data from analytical ultracentrifugation and time-resolved fluorescence anisotropy decay. In: Shuster TM, Laue TM, eds. Modern Analytical Ultracentrifugation. Boston: Birkhauser, 1994:189–205.CrossRefGoogle Scholar
  20. 20.
    Burian J, Ausio J, Phipps B et al. Hexamerization of RepA from the Escherichia coli plasmid pKL1. Biochemistry 2003; 42:10282–10287.PubMedCrossRefGoogle Scholar
  21. 21.
    Fleming KG, Hohl TM, Yu RC et al. A revised model for the oligomeric state of the N-ethylmaleimide-sensitive fusion protein, NSF. J Biol Chem 1998; 273:15675–15681.PubMedCrossRefGoogle Scholar
  22. 22.
    Lebowitz J, Lewis MS, Schuck P. Modern analytical ultracentrifugation in protein science: a tutorial review. Protein Sci 2002; 11:2067–2079.PubMedCrossRefGoogle Scholar
  23. 23.
    Gell D, Kong Y, Eaton SA et al. Biophysical characterization of the alpha-globin binding protein alpha-hemoglobin stabilizing protein. J Biol Chem 2002; 277:40602–40609.PubMedCrossRefGoogle Scholar
  24. 24.
    McRorie DK, Voelker PJ. Self-associating systems in the analytical ultracentrifuge. Beckman Instruments, Fullerton, CA: Beckman Instruments, Fullerton, CA, 1993.Google Scholar
  25. 25.
    Folta-Stogniew E, Williams KR. Determination of molecular masses of proteins in solution: implementation of an HPLC size exclusion chromatography and laser light scattering service in a core laboratory. J Biomol Tech 1999; 10:51–63.PubMedGoogle Scholar
  26. 26.
    Wyatt PJ. Light scattering and the absolute characterization of macromolecules. Anal Chim Acta 1993; 272:1–40.CrossRefGoogle Scholar
  27. 27.
    Philo JS, Aoki KH, Arakawa T et al. Dimerization of the extracellular domain of the erythropoietin (EPO) receptor by EPO: one high-affinity and one low-affinity interaction. Biochemistry 1996; 35:1681–1691.PubMedCrossRefGoogle Scholar
  28. 28.
    White JF, Grodnitzky J, Louis JM et al. Dimerization of the class A G protein-coupled neurotensin receptor NTS1 alters G protein interaction. Proc Natl Acad Sci USA 2007; 104:12199–12204.PubMedCrossRefGoogle Scholar
  29. 29.
    Philo JS. Is any measurement method optimal for all aggregate sizes and types? AAPS J 2006; 8:E564–571.PubMedCrossRefGoogle Scholar
  30. 30.
    Papish AL, Tari LW, Vogel HJ. Dynamic light scattering study of calmodulin-target peptide complexes. Biophys J 2002; 83:1455–1464.PubMedCrossRefGoogle Scholar
  31. 31.
    Khanova HA, Markossian KA, Kurganov BI et al. Mechanism of chaperone-like activity. Suppression of thermal aggregation of betaL-crystallin by alpha-crystallin. Biochemistry 2005; 44:15480–15487.PubMedCrossRefGoogle Scholar
  32. 32.
    Habel JE, Ohren JF, Borgstahl GEO. Dynamic light-scattering analysis of full-length human RPA14/32 dimer: purification, crystallization and self-association. Acta Crystallogr D 2001; 57:254–259.PubMedCrossRefGoogle Scholar
  33. 33.
    Lipfert J, Doniach S. Small-angle X-ray scattering from RNA, proteins and protein complexes. Annu Rev Biophys Biomol Struct 2007; 36:307–327.PubMedCrossRefGoogle Scholar
  34. 34.
    Koch MH, Vachette P, Svergun DI. Small-angle scattering: a view on the properties, structures and structural changes of biological macromolecules in solution. Q Rev Biophys 2003; 36:147–227.PubMedCrossRefGoogle Scholar
  35. 35.
    Jánosi A. The exponential distribution in small angle X-ray scattering. Theory and practice. Monatshefte für Chemie/Chemical Monthly 1993; 124:815–826.CrossRefGoogle Scholar
  36. 36.
    Rescic J, Vlachy V, Jamnik A et al. Osmotic Pressure, small-angle X-ray and dynamic light scattering studies of human serum albumin in aqueous solutions. J Colloid Interf Sci 2001; 239:49–57.CrossRefGoogle Scholar
  37. 37.
    Bada M, Walther D, Arcangioli B et al. Solution structural studies and low-resolution model of the Schizosaccharomyces pombe sap1 protein. J Mol Biol 2000; 300:563–574.PubMedCrossRefGoogle Scholar
  38. 38.
    Whitten AE, Jacques DA, Hammouda B et al. The structure of the KinA-Sda complex suggests an allosteric mechanism of histidine kinase inhibition. J Mol Biol 2007; 368:407–420.PubMedCrossRefGoogle Scholar
  39. 39.
    Schroder E, Willis AC, Ponting CP. Porcine natural-killer-enhancing factor-B: oligomerisation and identification as a calpain substrate in vitro. Biochim Biophys Acta 1998; 1383:279–291.PubMedCrossRefGoogle Scholar
  40. 40.
    Tang KH, Guo H, Yi W et al. Investigation of the conformational states of Wzz and the Wzz.O-antigen complex under near-physiological conditions. Biochemistry 2007; 46:11744–11752.PubMedCrossRefGoogle Scholar
  41. 41.
    Velazquez-Campoy A, Leavitt SA, Freire E. Characterization of protein-protein interactions by isothermal titration calorimetry. Methods Mol Biol 2004; 261:35–54.PubMedGoogle Scholar
  42. 42.
    Burrows SD, Doyle ML, Murphy KP et al. Determination of the monomer-dimer equilibrium of interleukin-8 reveals it is a monomer at physiological concentrations. Biochemistry 1994; 33:12741–12745.PubMedCrossRefGoogle Scholar
  43. 43.
    Schulte A, Czudnochowski N, Barboric M et al. Identification of a cyclin T-binding domain in Hexim1 and biochemical analysis of its binding competition with HIV-1 Tat. J Biol Chem 2005; 280:24968–24977.PubMedCrossRefGoogle Scholar
  44. 44.
    McPhail D, Cooper A. Thermodynamics and kinetics of dissociation of ligand-induced dimers of vancomycin antibiotics. J Chem Soc, Faraday Trans 1997; 93:2283–2289.CrossRefGoogle Scholar
  45. 45.
    Dingley AJ, Mackay JP, Chapman BE et al. Measuring protein self-association using pulsed-field-gradient NMR spectroscopy: application to myosin light chain 2. J Biomol NMR 1995; 6:321–328.PubMedCrossRefGoogle Scholar
  46. 46.
    Baden HA, Sarma SP, Kapust RB et al. The amino-terminal domain of human STAT4. Overproduction, purification and biophysical characterization. J Biol Chem 1998; 273:17109–17114.PubMedCrossRefGoogle Scholar
  47. 47.
    Nilges M. A calculation strategy for the structure determination of symmetric dimers by 1H NMR. Proteins 1993; 17:297–309.PubMedCrossRefGoogle Scholar
  48. 48.
    Lee W, Harvey TS, Yin Y et al. Solution structure of the tetrameric minimum transforming domain of p53. Nat Struct Biol 1994; 1:877–890.PubMedCrossRefGoogle Scholar
  49. 49.
    O’Donoghue SI, Chang X, Abseher R et al. Unraveling the symmetry ambiguity in a hexamer: calculation of the R6 human insulin structure. J Biomol NMR 2000; 16:93–108.PubMedCrossRefGoogle Scholar
  50. 50.
    Folkers PJM, Folmer RHA, Konings RNH et al. Overcoming the ambiguity problem encountered in the analysis of nuclear overhauser magnetic resonance spectra of symmetric dimer proteins. J Am Chem Soc 1993; 115:3798–3799.CrossRefGoogle Scholar
  51. 51.
    Otting G, Wüthrich K. Extended heteronuclear editing of 2D 1H NMR spectra of isotope-labeled proteins, using the X([omega]1, [omega]2) double half filter. J Magn Reson 1989; 85:586–594.Google Scholar
  52. 52.
    Drohat AC, Amburgey JC, Abildgaard F et al. Solution structure of rat apo-S100B(beta beta) as determined by NMR spectroscopy. Biochemistry 1996; 35:11577–11588.PubMedCrossRefGoogle Scholar
  53. 53.
    Jasanoff A, Fersht AR. Quantitative determination of helical propensities from trifluoroethanol titration curves. Biochemistry 1994; 33:2129–2135.PubMedCrossRefGoogle Scholar
  54. 54.
    Light-Wahl KJ, Schwartz BL, Smith RD. Observation of the noncovalent quaternary associations of proteins by electrospray ionization mass spectrometry. J Am Chem Soc 1994; 116:5271–5278.CrossRefGoogle Scholar
  55. 55.
    Keetch CA, Bromley EH, McCammon MG et al. L55P transthyretin accelerates subunit exchange and leads to rapid formation of hybrid tetramers. J Biol Chem 2005; 280:41667–41674.PubMedCrossRefGoogle Scholar
  56. 56.
    Rostom AA, Robinson CV. Detection of the intact GroEL chaperonin assembly by mass spectrometry. J Am Chem Soc 1999; 121:4718–4719.CrossRefGoogle Scholar
  57. 57.
    Hernandez H, Robinson CV. Determining the stoichiometry and interactions of macromolecular assemblies from mass spectrometry. Nat Protocols 2007; 2:715–726.CrossRefGoogle Scholar
  58. 58.
    Jameson DM, Seifried SE. Quantification of protein-protein interactions using fluorescence polarization. Methods 1999; 19:222–233.PubMedCrossRefGoogle Scholar
  59. 59.
    Maleki SJ, Royer CA, Hurlburt BK. MyoD-E12 heterodimers and MyoD-MyoD homodimers are equally stable. Biochemistry 1997; 36:6762–6767.PubMedCrossRefGoogle Scholar
  60. 60.
    Ryan DP, Duncan JL, Lee C et al. Assembly of the oncogenic DNA-binding complex LMO2-Ldb1-TAL1-E12. Proteins 2008; 70:1461–1474.PubMedCrossRefGoogle Scholar
  61. 61.
    de Lumley M, Hart DJ, Cooper MA et al. A biophysical characterisation of factors controlling dimerisation and selectivity in the NF-kappaB and NFAT families. J Mol Biol 2004; 339:1059–1075.PubMedCrossRefGoogle Scholar
  62. 62.
    Bakkenist CJ, Kastan MB. DNA damage activates ATM through intermolecular autophosphorylation and dimer dissociation. Nature 2003; 421:499–506.PubMedCrossRefGoogle Scholar
  63. 63.
    Hillar A, Culham DE, Vernikovska YI et al. Formation of an antiparallel, intermolecular coiled coil is associated with in vivo dimerization of osmosensor and osmoprotectant transporter ProP in Escherichia coli. Biochemistry 2005; 44:10170–10180.PubMedCrossRefGoogle Scholar
  64. 64.
    Westphal V, Rizzoli SO, Lauterbach MA et al. Video-rate far-field optical nanoscopy dissects synaptic vesicle movement. Science 2008; 320:246–249.PubMedCrossRefGoogle Scholar
  65. 65.
    Kimura H, Hieda M, Cook PR. Measuring histone and polymerase dynamics in living cells. Methods Enzymol 2003; 375:381–393.CrossRefGoogle Scholar
  66. 66.
    Bacia K, Schwille P. A dynamic view of cellular processes by in vivo fluorescence auto-and cross-correlation spectroscopy. Methods 2003; 29:74–85.PubMedCrossRefGoogle Scholar
  67. 67.
    Philip F, Sengupta P, Scarlata S. Signaling through a G protein-coupled receptor and its corresponding G protein follows a stoichiometrically limited model. J Biol Chem 2007; 282:19203.PubMedCrossRefGoogle Scholar
  68. 68.
    Kask P, Palo K, Ullmann D et al. Fluorescence-intensity distribution analysis and its application in biomolecular detection technology. Proc Natl Acad Sci USA 1999; 96:13756–13761.PubMedCrossRefGoogle Scholar
  69. 69.
    Saffarian S, Li Y, Elson EL et al. Oligomerization of the EGF receptor investigated by live cell fluorescence intensity distribution analysis. Biophys J 2007; 93:1021–1031.PubMedCrossRefGoogle Scholar
  70. 70.
    Förster T. Zwischenmolekulare energiewanderung und fluoreszenz. Ann Phys 1948; 437:55–75.CrossRefGoogle Scholar
  71. 71.
    Sapsford KE, Berti L, Medintz IL. Materials for fluorescence resonance energy transfer analysis: beyond traditional donor-acceptor combinations. Angew Chem Int Ed Engl 2006; 45:4562–4589.PubMedCrossRefGoogle Scholar
  72. 72.
    Rizzo MA, Springer G, Segawa K et al. Optimization of pairings and detection conditions for measurement of FRET between cyan and yellow fluorescent proteins. Microsc Microanal 2006; 12:238–254.PubMedCrossRefGoogle Scholar
  73. 73.
    Chilibeck KA, Wu T, Liang C et al. FRET analysis of in vivo dimerization by RNA-editing enzymes. J Biol Chem 2006; 281:16530–16535.PubMedCrossRefGoogle Scholar
  74. 74.
    Piston DW, Kremers GJ. Fluorescent protein FRET: the good, the bad and the ugly. Trends Biochem Sci 2007; 32:407–414.PubMedCrossRefGoogle Scholar
  75. 75.
    Evans NJ, Walker JW. Endothelin receptor dimers evaluated by FRET, ligand binding and calcium mobilization. Biophys J 2008; 95:483–492.PubMedCrossRefGoogle Scholar
  76. 76.
    Bacart J, Corbel C, Jockers R et al. The BRET technology and its application to screening assays. Biotechnol J 2008; 3:311–324.PubMedCrossRefGoogle Scholar
  77. 77.
    Gandiá J, Lluis C, Ferre S et al. Light resonance energy transfer-based methods in the study of G protein-coupled receptor oligomerization. Bioessays 2008; 30:82–89.PubMedCrossRefGoogle Scholar
  78. 78.
    Storez H, Scott MG, Issafras H et al. Homo-and hetero-oligomerization of beta-arrestins in living cells. J Biol Chem 2005; 280:40210–40215.PubMedCrossRefGoogle Scholar
  79. 79.
    Clayton AH, Walker F, Orchard SG et al. Ligand-induced dimer-tetramer transition during the activation of the cell surface epidermal growth factor receptor-A multidimensional microscopy analysis. J Biol Chem 2005; 280:30392–30399.PubMedCrossRefGoogle Scholar
  80. 80.
    Piston DW, Rizzo MA. FRET by fluorescence polarization microscopy. Methods Cell Biol 2008; 85:415–430.PubMedCrossRefGoogle Scholar
  81. 81.
    Gautier I, Tramier M, Durieux C et al. Homo-FRET microscopy in living cells to measure monomer-dimer transition of GFP-tagged proteins. Biophys J 2001; 80:3000–3008.PubMedCrossRefGoogle Scholar
  82. 82.
    Siemering KR, Golbik R, Sever R et al. Mutations that suppress the thermosensitivity of green fluorescent protein. Curr Biol 1996; 6:1653–1663.PubMedCrossRefGoogle Scholar
  83. 83.
    De Angelis DA, Miesenbock G, Zemelman BV et al. PRIM: proximity imaging of green fluorescent protein-tagged polypeptides. Proc Natl Acad Sci USA 1998; 95:12312–12316.PubMedCrossRefGoogle Scholar
  84. 84.
    Patschan S, Li H, Brodsky S et al. Probing lipid rafts with proximity imaging: actions of proatherogenic stimuli. Am J Physiol Heart Circ Physiol 2006; 290:H2210–2219.PubMedCrossRefGoogle Scholar
  85. 85.
    Sprague BL, McNally JG. FRAP analysis of binding: proper and fitting. Trends Cell Biol 2005; 15:84–91.PubMedCrossRefGoogle Scholar
  86. 86.
    Meyer T, Begitt A, Vinkemeier U. Green fluorescent protein-tagging reduces the nucleocytoplasmic shuttling specifically of unphosphorylated STAT1. Febs J 2007; 274:815–826.PubMedCrossRefGoogle Scholar
  87. 87.
    Stavreva DA, McNally JG. Fluorescence recovery after photobleaching (FRAP) methods for visualizing protein dynamics in living mammalian cell nuclei. Methods Enzymol 2004; 375:443–455.PubMedCrossRefGoogle Scholar
  88. 88.
    Fields S, Song O. A novel genetic system to detect protein protein interactions. Nature 1989; 340:245–246.PubMedCrossRefGoogle Scholar
  89. 89.
    MacDonald PN, ed. Two-Hybrid Systems: Methods and Protocols. New York: Springer-Verlag; 2001; No. 177.CrossRefGoogle Scholar
  90. 90.
    Tsai WC, Pan ZJ, Hsiao YY et al. Interactions of B-class complex proteins involved in tepal development in Phalaenopsis orchid. Plant Cell Physiol Vol 49; 2008:814–824.CrossRefGoogle Scholar
  91. 91.
    Stella S, Spurio R, Falconi M et al. Nature and mechanism of the in vivo oligomerization of nucleoid protein H-NS. EMBO J 2005; 24:2896–2905.PubMedCrossRefGoogle Scholar
  92. 92.
    Villalobos V, Naik S, Piwnica-Worms D. Current state of imaging protein-protein interactions in vivo with genetically encoded reporters. Annu Rev Biomed Eng 2007; 9:321–349.PubMedCrossRefGoogle Scholar
  93. 93.
    Benton R, Sachse S, Michnick SW et al. Atypical membrane topology and heteromeric function of Drosophila odorant receptors in vivo. PLoS Biol 2006; 4:e20.PubMedCrossRefGoogle Scholar
  94. 94.
    Saka Y, Hagemann AI, Piepenburg O et al. Nuclear accumulation of Smad complexes occurs only after the midblastula transition in Xenopus. Development 2007; 134:4209–4218.PubMedCrossRefGoogle Scholar
  95. 95.
    Shyu YJ, Hiatt SM, Duren HM et al. Visualization of protein interactions in living Caenorhabditis elegans using bimolecular fluorescence complementation analysis. Nat Protoc 2008; 3:588–596.PubMedCrossRefGoogle Scholar
  96. 96.
    Magliery TJ, Wilson CG, Pan W et al. Detecting protein-protein interactions with a green fluorescent protein fragment reassembly trap: scope and mechanism. J Am Chem Soc 2005; 127:146–157.PubMedCrossRefGoogle Scholar
  97. 97.
    Galarneau A, Primeau M, Trudeau LE et al. Beta-lactamase protein fragment complementation assays as in vivo and in vitro sensors of protein protein interactions. Nat Biotechnol 2002; 20:619–622.PubMedCrossRefGoogle Scholar
  98. 98.
    Donadini R, Liew CW, Kwan AH et al. Crystal and solution structures of a superantigen from Yersinia pseudotuberculosis reveal a jelly-roll fold. Structure 2004; 12:145–156.PubMedCrossRefGoogle Scholar
  99. 99.
    Johnson ML, Correia JJ, Yphantis DA et al. Analysis of data from the analytical ultracentrifuge by nonlinear least-squares techniques. Biophys J 1981; 36:575–588.PubMedCrossRefGoogle Scholar
  100. 100.
    Junius FK, Mackay JP, Bubb WA et al. Nuclear magnetic resonance characterization of the Jun leucine zipper domain: unusual properties of coiled-coil interfacial polar residues. Biochemistry 1995; 34:6164–6174.PubMedCrossRefGoogle Scholar

Copyright information

© Landes Bioscience and Springer Science+Business Media 2012

Authors and Affiliations

  • David A. Gell
    • 1
    • 2
  • Richard P. Grant
    • 1
  • Joel P. Mackay
    • 1
  1. 1.School of Molecular BioscienceUniversity of SydneySydneyAustralia
  2. 2.Menzies Research InstituteUniversity of TasmaniaHobartAustralia

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