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. 2005 Jun;6(4):236–243. doi: 10.1002/cfg.477

Proteomic Analysis of Colorectal Cancer: Prefractionation Strategies Using two-Dimensional Free-Flow Electrophoresis

Robert L Moritz 1, Anita R Skandarajah 1, Hong Ji 1, Richard J Simpson 1,✉
PMCID: PMC2447484  PMID: 18629191

Abstract

This review deals with the application of a new prefractionation tool, free-flow electrophoresis (FFE), for proteomic analysis of colorectal cancer (CRC). CRC is a leading cause of cancer death in the Western world. Early detection is the single most important factor influencing outcome of CRC patients. If identified while the disease is still localized, CRC is treatable. To improve outcomes for CRC patients there is a pressing need to identify biomarkers for early detection (diagnostic markers), prognosis (prognostic indicators), tumour responses (predictive markers) and disease recurrence (monitoring markers). Despite recent advances in the use of genomic analysis for risk assessment, in the area of biomarker identification genomic methods alone have yet to produce reliable candidate markers for CRC. For this reason, attention is being directed towards proteomics as a complementary analytical tool for biomarker identification. Here we describe a proteomics separation tool, which uses a combination of continuous FFE, a liquid-based isoelectric focusing technique, in the first dimension, followed by rapid reversed-phase HPLC (1–6 min/analysis) in the second dimension. We have optimized imaging software to present the FFE/RP-HPLC data in a virtual 2D gel-like format. The advantage of this liquid based fractionation system over traditional gel-based fractionation systems is the ability to fractionate large quantity protein samples. Unlike 2D gels, the method is applicable to both high-Mr proteins and small peptides, which are difficult to separate, and in the case of peptides, are not retained in standard 2D gels.

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Selected References

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  1. Akerström B., Brodin T., Reis K., Björck L. Protein G: a powerful tool for binding and detection of monoclonal and polyclonal antibodies. J Immunol. 1985 Oct;135(4):2589–2592. [PubMed] [Google Scholar]
  2. Anderson N. Leigh, Polanski Malu, Pieper Rembert, Gatlin Tina, Tirumalai Radhakrishna S., Conrads Thomas P., Veenstra Timothy D., Adkins Joshua N., Pounds Joel G., Fagan Richard. The human plasma proteome: a nonredundant list developed by combination of four separate sources. Mol Cell Proteomics. 2004 Jan 12;3(4):311–326. doi: 10.1074/mcp.M300127-MCP200. [DOI] [PubMed] [Google Scholar]
  3. Balk Steven P., Ko Yoo-Joung, Bubley Glenn J. Biology of prostate-specific antigen. J Clin Oncol. 2003 Jan 15;21(2):383–391. doi: 10.1200/JCO.2003.02.083. [DOI] [PubMed] [Google Scholar]
  4. Bier M., Long T. Recycling isoelectric focusing: use of simple buffers. J Chromatogr. 1992 Jun 26;604(1):73–83. doi: 10.1016/0021-9673(92)85530-7. [DOI] [PubMed] [Google Scholar]
  5. Bjellqvist B., Ek K., Righetti P. G., Gianazza E., Görg A., Westermeier R., Postel W. Isoelectric focusing in immobilized pH gradients: principle, methodology and some applications. J Biochem Biophys Methods. 1982 Sep;6(4):317–339. doi: 10.1016/0165-022x(82)90013-6. [DOI] [PubMed] [Google Scholar]
  6. Björck L., Kronvall G. Purification and some properties of streptococcal protein G, a novel IgG-binding reagent. J Immunol. 1984 Aug;133(2):969–974. [PubMed] [Google Scholar]
  7. Blackstock W. P., Weir M. P. Proteomics: quantitative and physical mapping of cellular proteins. Trends Biotechnol. 1999 Mar;17(3):121–127. doi: 10.1016/s0167-7799(98)01245-1. [DOI] [PubMed] [Google Scholar]
  8. Brunet Sylvain, Thibault Pierre, Gagnon Etienne, Kearney Paul, Bergeron John J. M., Desjardins Michel. Organelle proteomics: looking at less to see more. Trends Cell Biol. 2003 Dec;13(12):629–638. doi: 10.1016/j.tcb.2003.10.006. [DOI] [PubMed] [Google Scholar]
  9. Burggraf D., Weber G., Lottspeich F. Free flow-isoelectric focusing of human cellular lysates as sample preparation for protein analysis. Electrophoresis. 1995 Jun;16(6):1010–1015. doi: 10.1002/elps.11501601169. [DOI] [PubMed] [Google Scholar]
  10. Bushey M. M., Jorgenson J. W. Automated instrumentation for comprehensive two-dimensional high-performance liquid chromatography of proteins. Anal Chem. 1990 Jan 15;62(2):161–167. doi: 10.1021/ac00201a015. [DOI] [PubMed] [Google Scholar]
  11. Cargile Benjamin J., Stephenson James L., Jr An alternative to tandem mass spectrometry: isoelectric point and accurate mass for the identification of peptides. Anal Chem. 2004 Jan 15;76(2):267–275. doi: 10.1021/ac0352070. [DOI] [PubMed] [Google Scholar]
  12. Celis J. E., Ostergaard M., Rasmussen H. H., Gromov P., Gromova I., Varmark H., Palsdottir H., Magnusson N., Andersen I., Basse B. A comprehensive protein resource for the study of bladder cancer: http://biobase.dk/cgi-bin/celis. Electrophoresis. 1999 Feb;20(2):300–309. doi: 10.1002/(SICI)1522-2683(19990201)20:2<300::AID-ELPS300>3.0.CO;2-Q. [DOI] [PubMed] [Google Scholar]
  13. Celis J. E., Wolf H., Ostergaard M. Bladder squamous cell carcinoma biomarkers derived from proteomics. Electrophoresis. 2000 Jun;21(11):2115–2121. doi: 10.1002/1522-2683(20000601)21:11<2115::AID-ELPS2115>3.0.CO;2-K. [DOI] [PubMed] [Google Scholar]
  14. Chung D. C. The genetic basis of colorectal cancer: insights into critical pathways of tumorigenesis. Gastroenterology. 2000 Sep;119(3):854–865. doi: 10.1053/gast.2000.16507. [DOI] [PubMed] [Google Scholar]
  15. Collins Judith F., Lieberman David A., Durbin Theodore E., Weiss David G., Veterans Affairs Cooperative Study #380 Group Accuracy of screening for fecal occult blood on a single stool sample obtained by digital rectal examination: a comparison with recommended sampling practice. Ann Intern Med. 2005 Jan 18;142(2):81–85. doi: 10.7326/0003-4819-142-2-200501180-00006. [DOI] [PubMed] [Google Scholar]
  16. Cox Brian, Kislinger Thomas, Emili Andrew. Integrating gene and protein expression data: pattern analysis and profile mining. Methods. 2005 Jan 12;35(3):303–314. doi: 10.1016/j.ymeth.2004.08.021. [DOI] [PubMed] [Google Scholar]
  17. Crawford Nigel P. S., Colliver Daniel W., Galandiuk Susan. Tumor markers and colorectal cancer: utility in management. J Surg Oncol. 2003 Dec;84(4):239–248. doi: 10.1002/jso.10325. [DOI] [PubMed] [Google Scholar]
  18. Domon Bruno, Alving Kim, He Tao, Ryan Terence E., Patterson Scott D. Enabling parallel protein analysis through mass spectrometry. Curr Opin Mol Ther. 2002 Dec;4(6):577–586. [PubMed] [Google Scholar]
  19. Duffy M. J., van Dalen A., Haglund C., Hansson L., Klapdor R., Lamerz R., Nilsson O., Sturgeon C., Topolcan O. Clinical utility of biochemical markers in colorectal cancer: European Group on Tumour Markers (EGTM) guidelines. Eur J Cancer. 2003 Apr;39(6):718–727. doi: 10.1016/s0959-8049(02)00811-0. [DOI] [PubMed] [Google Scholar]
  20. Egen N. B., Bliss M., Mayersohn M., Owens S. M., Arnold L., Bier M. Isolation of monoclonal antibodies to phencyclidine from ascites fluid by preparative isoelectric focusing in the Rotofor. Anal Biochem. 1988 Aug 1;172(2):488–494. doi: 10.1016/0003-2697(88)90472-1. [DOI] [PubMed] [Google Scholar]
  21. Etzioni Ruth, Urban Nicole, Ramsey Scott, McIntosh Martin, Schwartz Stephen, Reid Brian, Radich Jerald, Anderson Garnet, Hartwell Leland. The case for early detection. Nat Rev Cancer. 2003 Apr;3(4):243–252. doi: 10.1038/nrc1041. [DOI] [PubMed] [Google Scholar]
  22. Faupel M., Barzaghi B., Gelfi C., Righetti P. G. Isoelectric protein purification by orthogonally coupled hydraulic and electric transports in a segmented immobilized pH gradient. J Biochem Biophys Methods. 1987 Dec;15(3-4):147–161. doi: 10.1016/0165-022x(87)90114-x. [DOI] [PubMed] [Google Scholar]
  23. Fearon E. R. Molecular genetic studies of the adenoma-carcinoma sequence. Adv Intern Med. 1994;39:123–147. [PubMed] [Google Scholar]
  24. Fearon E. R., Vogelstein B. A genetic model for colorectal tumorigenesis. Cell. 1990 Jun 1;61(5):759–767. doi: 10.1016/0092-8674(90)90186-i. [DOI] [PubMed] [Google Scholar]
  25. Ferguson P. Lee, Smith Richard D. Proteome analysis by mass spectrometry. Annu Rev Biophys Biomol Struct. 2003 Jan 28;32:399–424. doi: 10.1146/annurev.biophys.32.110601.141854. [DOI] [PubMed] [Google Scholar]
  26. Fountoulakis Michael, Juranville Jean François. Enrichment of low-abundance brain proteins by preparative electrophoresis. Anal Biochem. 2003 Feb 15;313(2):267–282. doi: 10.1016/s0003-2697(02)00617-6. [DOI] [PubMed] [Google Scholar]
  27. Govorukhina N. I., Keizer-Gunnink A., van der Zee A. G. J., de Jong S., de Bruijn H. W. A., Bischoff R. Sample preparation of human serum for the analysis of tumor markers. Comparison of different approaches for albumin and gamma-globulin depletion. J Chromatogr A. 2003 Aug 15;1009(1-2):171–178. doi: 10.1016/s0021-9673(03)00921-x. [DOI] [PubMed] [Google Scholar]
  28. Guss B., Eliasson M., Olsson A., Uhlén M., Frej A. K., Jörnvall H., Flock J. I., Lindberg M. Structure of the IgG-binding regions of streptococcal protein G. EMBO J. 1986 Jul;5(7):1567–1575. doi: 10.1002/j.1460-2075.1986.tb04398.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  29. Gygi S. P., Rochon Y., Franza B. R., Aebersold R. Correlation between protein and mRNA abundance in yeast. Mol Cell Biol. 1999 Mar;19(3):1720–1730. doi: 10.1128/mcb.19.3.1720. [DOI] [PMC free article] [PubMed] [Google Scholar]
  30. Görg A., Boguth G., Obermaier C., Weiss W. Two-dimensional electrophoresis of proteins in an immobilized pH 4-12 gradient. Electrophoresis. 1998 Jun;19(8-9):1516–1519. doi: 10.1002/elps.1150190850. [DOI] [PubMed] [Google Scholar]
  31. Görg A., Obermaier C., Boguth G., Harder A., Scheibe B., Wildgruber R., Weiss W. The current state of two-dimensional electrophoresis with immobilized pH gradients. Electrophoresis. 2000 Apr;21(6):1037–1053. doi: 10.1002/(SICI)1522-2683(20000401)21:6<1037::AID-ELPS1037>3.0.CO;2-V. [DOI] [PubMed] [Google Scholar]
  32. Hall N. R., Finan P. J., Stephenson B. M., Purves D. A., Cooper E. H. The role of CA-242 and CEA in surveillance following curative resection for colorectal cancer. Br J Cancer. 1994 Sep;70(3):549–553. doi: 10.1038/bjc.1994.343. [DOI] [PMC free article] [PubMed] [Google Scholar]
  33. Henzel W. J., Billeci T. M., Stults J. T., Wong S. C., Grimley C., Watanabe C. Identifying proteins from two-dimensional gels by molecular mass searching of peptide fragments in protein sequence databases. Proc Natl Acad Sci U S A. 1993 Jun 1;90(11):5011–5015. doi: 10.1073/pnas.90.11.5011. [DOI] [PMC free article] [PubMed] [Google Scholar]
  34. Henzel William J., Watanabe Colin, Stults John T. Protein identification: the origins of peptide mass fingerprinting. J Am Soc Mass Spectrom. 2003 Sep;14(9):931–942. doi: 10.1016/S1044-0305(03)00214-9. [DOI] [PubMed] [Google Scholar]
  35. Hoffmann P., Ji H., Moritz R. L., Connolly L. M., Frecklington D. F., Layton M. J., Eddes J. S., Simpson R. J. Continuous free-flow electrophoresis separation of cytosolic proteins from the human colon carcinoma cell line LIM 1215: a non two-dimensional gel electrophoresis-based proteome analysis strategy. Proteomics. 2001 Jul;1(7):807–818. doi: 10.1002/1615-9861(200107)1:7<807::AID-PROT807>3.0.CO;2-6. [DOI] [PubMed] [Google Scholar]
  36. Holten-Andersen Mads N., Christensen Ib Jarle, Nielsen Hans Jørgen, Stephens Ross W., Jensen Vibeke, Nielsen Ole Haagen, Sørensen Steen, Overgaard Jens, Lilja Hans, Harris Adrian. Total levels of tissue inhibitor of metalloproteinases 1 in plasma yield high diagnostic sensitivity and specificity in patients with colon cancer. Clin Cancer Res. 2002 Jan;8(1):156–164. [PubMed] [Google Scholar]
  37. Jung E., Heller M., Sanchez J. C., Hochstrasser D. F. Proteomics meets cell biology: the establishment of subcellular proteomes. Electrophoresis. 2000 Oct;21(16):3369–3377. doi: 10.1002/1522-2683(20001001)21:16<3369::AID-ELPS3369>3.0.CO;2-7. [DOI] [PubMed] [Google Scholar]
  38. Klose J. Protein mapping by combined isoelectric focusing and electrophoresis of mouse tissues. A novel approach to testing for induced point mutations in mammals. Humangenetik. 1975;26(3):231–243. doi: 10.1007/BF00281458. [DOI] [PubMed] [Google Scholar]
  39. Lewis T. S., Hunt J. B., Aveline L. D., Jonscher K. R., Louie D. F., Yeh J. M., Nahreini T. S., Resing K. A., Ahn N. G. Identification of novel MAP kinase pathway signaling targets by functional proteomics and mass spectrometry. Mol Cell. 2000 Dec;6(6):1343–1354. doi: 10.1016/s1097-2765(00)00132-5. [DOI] [PubMed] [Google Scholar]
  40. Liotta Lance A., Ferrari Mauro, Petricoin Emanuel. Clinical proteomics: written in blood. Nature. 2003 Oct 30;425(6961):905–905. doi: 10.1038/425905a. [DOI] [PubMed] [Google Scholar]
  41. Lottspeich F. Proteome Analysis: A Pathway to the Functional Analysis of Proteins. Angew Chem Int Ed Engl. 1999 Sep;38(17):2476–2492. doi: 10.1002/(sici)1521-3773(19990903)38:17<2476::aid-anie2476>3.0.co;2-s. [DOI] [PubMed] [Google Scholar]
  42. Moritz Robert L., Ji Hong, Schütz Frédéric, Connolly Lisa M., Kapp Eugene A., Speed Terence P., Simpson Richard J. A proteome strategy for fractionating proteins and peptides using continuous free-flow electrophoresis coupled off-line to reversed-phase high-performance liquid chromatography. Anal Chem. 2004 Aug 15;76(16):4811–4824. doi: 10.1021/ac049717l. [DOI] [PubMed] [Google Scholar]
  43. Nam Myeong J., Kee Mee K., Kuick Rork, Hanash Samir M. Identification of defensin alpha6 as a potential biomarker in colon adenocarcinoma. J Biol Chem. 2004 Dec 21;280(9):8260–8265. doi: 10.1074/jbc.M410054200. [DOI] [PubMed] [Google Scholar]
  44. O'Farrell P. H. High resolution two-dimensional electrophoresis of proteins. J Biol Chem. 1975 May 25;250(10):4007–4021. [PMC free article] [PubMed] [Google Scholar]
  45. Pandey A., Podtelejnikov A. V., Blagoev B., Bustelo X. R., Mann M., Lodish H. F. Analysis of receptor signaling pathways by mass spectrometry: identification of vav-2 as a substrate of the epidermal and platelet-derived growth factor receptors. Proc Natl Acad Sci U S A. 2000 Jan 4;97(1):179–184. doi: 10.1073/pnas.97.1.179. [DOI] [PMC free article] [PubMed] [Google Scholar]
  46. Pappin D. J., Hojrup P., Bleasby A. J. Rapid identification of proteins by peptide-mass fingerprinting. Curr Biol. 1993 Jun 1;3(6):327–332. doi: 10.1016/0960-9822(93)90195-t. [DOI] [PubMed] [Google Scholar]
  47. Patterson Scott D. Proteomics: evolution of the technology. Biotechniques. 2003 Sep;35(3):440–444. doi: 10.2144/03353ap01. [DOI] [PubMed] [Google Scholar]
  48. Pieper Rembert, Su Qin, Gatlin Christine L., Huang Shih-Ting, Anderson N. Leigh, Steiner Sandra. Multi-component immunoaffinity subtraction chromatography: an innovative step towards a comprehensive survey of the human plasma proteome. Proteomics. 2003 Apr;3(4):422–432. doi: 10.1002/pmic.200390057. [DOI] [PubMed] [Google Scholar]
  49. Ramsby M. L., Makowski G. S. Differential detergent fractionation of eukaryotic cells. Analysis by two-dimensional gel electrophoresis. Methods Mol Biol. 1999;112:53–66. doi: 10.1385/1-59259-584-7:53. [DOI] [PubMed] [Google Scholar]
  50. Ramsby M. L., Makowski G. S., Khairallah E. A. Differential detergent fractionation of isolated hepatocytes: biochemical, immunochemical and two-dimensional gel electrophoresis characterization of cytoskeletal and noncytoskeletal compartments. Electrophoresis. 1994 Feb;15(2):265–277. doi: 10.1002/elps.1150150146. [DOI] [PubMed] [Google Scholar]
  51. Ransohoff David F. Lessons from controversy: ovarian cancer screening and serum proteomics. J Natl Cancer Inst. 2005 Feb 16;97(4):315–319. doi: 10.1093/jnci/dji054. [DOI] [PubMed] [Google Scholar]
  52. Righetti Pier Giorgio, Castagna Annalisa, Antonioli Paolo, Boschetti Egisto. Prefractionation techniques in proteome analysis: the mining tools of the third millennium. Electrophoresis. 2005 Jan;26(2):297–319. doi: 10.1002/elps.200406189. [DOI] [PubMed] [Google Scholar]
  53. Righetti Pier Giorgio, Castagna Annalisa, Herbert Ben, Reymond Frederic, Rossier Joël S. Prefractionation techniques in proteome analysis. Proteomics. 2003 Aug;3(8):1397–1407. doi: 10.1002/pmic.200300472. [DOI] [PubMed] [Google Scholar]
  54. Ross D. T., Scherf U., Eisen M. B., Perou C. M., Rees C., Spellman P., Iyer V., Jeffrey S. S., Van de Rijn M., Waltham M. Systematic variation in gene expression patterns in human cancer cell lines. Nat Genet. 2000 Mar;24(3):227–235. doi: 10.1038/73432. [DOI] [PubMed] [Google Scholar]
  55. Scherf U., Ross D. T., Waltham M., Smith L. H., Lee J. K., Tanabe L., Kohn K. W., Reinhold W. C., Myers T. G., Andrews D. T. A gene expression database for the molecular pharmacology of cancer. Nat Genet. 2000 Mar;24(3):236–244. doi: 10.1038/73439. [DOI] [PubMed] [Google Scholar]
  56. Simpson R. J., Dorow D. S. Cancer proteomics: from signaling networks to tumor markers. Trends Biotechnol. 2001 Oct;19(10 Suppl):S40–S48. doi: 10.1016/S0167-7799(01)01801-7. [DOI] [PubMed] [Google Scholar]
  57. Simpson R. J., Hammacher A., Smith D. K., Matthews J. M., Ward L. D. Interleukin-6: structure-function relationships. Protein Sci. 1997 May;6(5):929–955. doi: 10.1002/pro.5560060501. [DOI] [PMC free article] [PubMed] [Google Scholar]
  58. Tian Qiang, Stepaniants Serguei B., Mao Mao, Weng Lee, Feetham Megan C., Doyle Michelle J., Yi Eugene C., Dai Hongyue, Thorsson Vesteinn, Eng Jimmy. Integrated genomic and proteomic analyses of gene expression in Mammalian cells. Mol Cell Proteomics. 2004 Jul 6;3(10):960–969. doi: 10.1074/mcp.M400055-MCP200. [DOI] [PubMed] [Google Scholar]
  59. Travis J., Pannell R. Selective removal of albumin from plasma by affinity chromatography. Clin Chim Acta. 1973 Nov 23;49(1):49–52. doi: 10.1016/0009-8981(73)90341-0. [DOI] [PubMed] [Google Scholar]
  60. Van Snick J., Cayphas S., Vink A., Uyttenhove C., Coulie P. G., Rubira M. R., Simpson R. J. Purification and NH2-terminal amino acid sequence of a T-cell-derived lymphokine with growth factor activity for B-cell hybridomas. Proc Natl Acad Sci U S A. 1986 Dec;83(24):9679–9683. doi: 10.1073/pnas.83.24.9679. [DOI] [PMC free article] [PubMed] [Google Scholar]
  61. Van Snick J., Vink A., Cayphas S., Uyttenhove C. Interleukin-HP1, a T cell-derived hybridoma growth factor that supports the in vitro growth of murine plasmacytomas. J Exp Med. 1987 Mar 1;165(3):641–649. doi: 10.1084/jem.165.3.641. [DOI] [PMC free article] [PubMed] [Google Scholar]
  62. Verhagen A. M., Ekert P. G., Pakusch M., Silke J., Connolly L. M., Reid G. E., Moritz R. L., Simpson R. J., Vaux D. L. Identification of DIABLO, a mammalian protein that promotes apoptosis by binding to and antagonizing IAP proteins. Cell. 2000 Jul 7;102(1):43–53. doi: 10.1016/s0092-8674(00)00009-x. [DOI] [PubMed] [Google Scholar]
  63. Wagner K., Racaityte K., Unger K. K., Miliotis T., Edholm L. E., Bischoff R., Marko-Varga G. Protein mapping by two-dimensional high performance liquid chromatography. J Chromatogr A. 2000 Oct 6;893(2):293–305. doi: 10.1016/s0021-9673(00)00736-6. [DOI] [PubMed] [Google Scholar]
  64. Washburn M. P., Wolters D., Yates J. R., 3rd Large-scale analysis of the yeast proteome by multidimensional protein identification technology. Nat Biotechnol. 2001 Mar;19(3):242–247. doi: 10.1038/85686. [DOI] [PubMed] [Google Scholar]
  65. Winawer S. J., Zauber A. G., Ho M. N., O'Brien M. J., Gottlieb L. S., Sternberg S. S., Waye J. D., Schapiro M., Bond J. H., Panish J. F. Prevention of colorectal cancer by colonoscopic polypectomy. The National Polyp Study Workgroup. N Engl J Med. 1993 Dec 30;329(27):1977–1981. doi: 10.1056/NEJM199312303292701. [DOI] [PubMed] [Google Scholar]
  66. Wu Christine C., MacCoss Michael J. Shotgun proteomics: tools for the analysis of complex biological systems. Curr Opin Mol Ther. 2002 Jun;4(3):242–250. [PubMed] [Google Scholar]
  67. Zhang J. G., Farley A., Nicholson S. E., Willson T. A., Zugaro L. M., Simpson R. J., Moritz R. L., Cary D., Richardson R., Hausmann G. The conserved SOCS box motif in suppressors of cytokine signaling binds to elongins B and C and may couple bound proteins to proteasomal degradation. Proc Natl Acad Sci U S A. 1999 Mar 2;96(5):2071–2076. doi: 10.1073/pnas.96.5.2071. [DOI] [PMC free article] [PubMed] [Google Scholar]
  68. Zischka Hans, Weber Gerhard, Weber Peter J. A., Posch Anton, Braun Ralf J., Bühringer Dietmute, Schneider Ulrich, Nissum Mikkel, Meitinger Thomas, Ueffing Marius. Improved proteome analysis of Saccharomyces cerevisiae mitochondria by free-flow electrophoresis. Proteomics. 2003 Jun;3(6):906–916. doi: 10.1002/pmic.200300376. [DOI] [PubMed] [Google Scholar]
  69. Zugaro L. M., Reid G. E., Ji H., Eddes J. S., Murphy A. C., Burgess A. W., Simpson R. J. Characterization of rat brain stathmin isoforms by two-dimensional gel electrophoresis-matrix assisted laser desorption/ionization and electrospray ionization-ion trap mass spectrometry. Electrophoresis. 1998 May;19(5):867–876. doi: 10.1002/elps.1150190544. [DOI] [PubMed] [Google Scholar]
  70. Zuo Xun, Speicher David W. Comprehensive analysis of complex proteomes using microscale solution isoelectrofocusing prior to narrow pH range two-dimensional electrophoresis. Proteomics. 2002 Jan;2(1):58–68. [PubMed] [Google Scholar]

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