Toxicological Reviews

, Volume 22, Issue 1, pp 53–64 | Cite as


Mechanisms of Cytotoxicity
  • Michael J. Lord
  • Nicholas A. Jolliffe
  • Catherine J. Marsden
  • Cassandra S. C. Pateman
  • Daniel C. Smith
  • Robert A. Spooner
  • Peter D. Watson
  • Lynne M. Roberts
Review Article


Ricin is a heterodimeric protein produced in the seeds of the castor oil plant (Ricinus communis). It is exquisitely potent to mammalian cells, being able to fatally disrupt protein synthesis by attacking the Achilles heel of the ribosome. For this enzyme to reach its substrate, it must not only negotiate the endomembrane system but it must also cross an internal membrane and avoid complete degradation without compromising its activity in any way. Cell entry by ricin involves a series of steps: (i) binding, via the ricin B chain (RTB), to a range of cell surface glycolipids or glycoproteins having β-1,4-linked galactose residues; (ii) uptake into the cell by endocytosis; (iii) entry of the toxin into early endosomes; (iv) transfer, by vesicular transport, of ricin from early endosomes to the trans-Golgi network; (v) retrograde vesicular transport through the Golgi complex to reach the endoplasmic reticulum; (vi) reduction of the disulphide bond connecting the ricin A chain (RTA) and the RTB; (vii) partial unfolding of the RTA to render it translocationally-competent to cross the endoplasmic reticulum (ER) membrane via the Sec61p translocon in a manner similar to that followed by misfolded ER proteins that, once recognised, are targeted to the ER-associated protein degradation (ERAD) machinery; (viii) avoiding, at least in part, ubiquitination that would lead to rapid degradation by cytosolic proteasomes immediately after membrane translocation when it is still partially unfolded; (ix) refolding into its protease-resistant, biologically active conformation; and (x) interaction with the ribosome to catalyse the depurination reaction.

It is clear that ricin can take advantage of many target cell molecules, pathways and processes. It has been reported that a single molecule of ricin reaching the cytosol can kill that cell as a consequence of protein synthesis inhibition. The ready availability of ricin, coupled to its extreme potency when administered intravenously or if inhaled, has identified this protein toxin as a potential biological warfare agent. Therapeutically, its cytotoxicity has encouraged the use of ricin in ‘magic bullets’ to specifically target and destroy cancer cells, and the unusual intracellular trafficking properties of ricin potentially permit its development as a vaccine vector.

Combining our understanding of the ricin structure with ways to cripple its unwanted properties (its enzymatic activity and promotion of vascular leak whilst retaining protein stability and important immunodominant epitopes), will also be crucial in the development of a long awaited protective vaccine against this toxin.


Endoplasmic Reticulum Late Endosome Shiga Toxin Endoplasmic Reticulum Lumen Coatomer Protein 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


  1. 1.
    Lord JM, Roberts LM. Toxin entry: retrograde transport through the secretory pathway. J Cell Biol 1998; 140: 733–6PubMedCrossRefGoogle Scholar
  2. 2.
    Eiklid K, Olsnes S, Pihl A. Entry of lethal doses of abrin, ricin and modeccin into the cytosol of HeLa cells. Exp Cell Res 1980; 126: 321–6PubMedCrossRefGoogle Scholar
  3. 3.
    Olsnes S, Pihl A. Toxic lectins and related proteins. In: Cohen P, van Heyningen S, editors. Molecular action of toxins and viruses. Amsterdam: Elsevier, 1982: 51–105CrossRefGoogle Scholar
  4. 4.
    Griffiths GD, Rice P, Allenby AC, et al. Inhalation toxicology and histopathology of ricin and abrin toxins. Inhal Toxicol 1995; 7: 269–88CrossRefGoogle Scholar
  5. 5.
    United Nations Convention on the prohibition of the development, production, stockpiling and use of chemical weapons and on their destruction; 1993 Jan 13; ParisGoogle Scholar
  6. 6.
    Kreitman RJ. Immunotoxins in cancer therapy. Curr Opin Immunol 1999; 11: 570–8PubMedCrossRefGoogle Scholar
  7. 7.
    Frankel AE, Kreitman RJ, Sausville EA. Targeted toxins. Clin Cancer Res 2000; 6: 326–34PubMedGoogle Scholar
  8. 8.
    Smith DC, Gallimore A, Jones E, et al. Exogenous peptides delivered by ricin require processing by signal peptidase for transporter associated with antigen processing-independent MHC class 1-restricted presentation. J Immunol 2002; 169: 99–107PubMedGoogle Scholar
  9. 9.
    Smith DC, Lord JM, Roberts LM, et al. 1st class ticket to class 1: protein toxins as pathfinders for antigen presentation. Traffic 2002; 3: 697–704PubMedCrossRefGoogle Scholar
  10. 10.
    Stirpe F, Barbieri L, Battelli MG, et al. Ribosome inactivating proteins from plants: present studies and future prospects. Biotechnology (N Y) 1992; 10: 405–11CrossRefGoogle Scholar
  11. 11.
    Barbieri L, Battelli MG, Stirpe F. Ribosome inactivating proteins from plants. Biochim Biophys Acta 1993; 1154: 237–82PubMedCrossRefGoogle Scholar
  12. 12.
    Hartley MR, Chaddock JA, Bonness MS. The structure and function of ribosome inactivating proteins. Trends Plant Sci 1996; 1: 254–9CrossRefGoogle Scholar
  13. 13.
    Peumans WJ, Hao Q, van Damme EJ. Ribosome-inactivating proteins from plants: more that RNA N-glycosidases? FASEB J 2001; 15: 1493–506PubMedCrossRefGoogle Scholar
  14. 14.
    Montford W, Villafranca JE, Monzingo AF, et al. The three-dimensional structure of ricin at 2.8A resolution. J Biol Chem 1987; 262: 5398–403Google Scholar
  15. 15.
    Rutenber E, Katzin BJ, Ernst S, et al. Crystallographic refinement of ricin to 2.5Å. Proteins 1991; 10: 240–50PubMedCrossRefGoogle Scholar
  16. 16.
    Rutenber E, Robertus JD. Sructure of ricin B-chain at 2.5Å resolution. Proteins 1991; 10: 260–9PubMedCrossRefGoogle Scholar
  17. 17.
    Villafranca JE, Robertus JD. Ricin B chain is the product of gene duplication. J Biol Chem 1981; 256: 554–6PubMedGoogle Scholar
  18. 18.
    Katzin BJ, Collins EJ, Robertus JD. Structure of ricin A-chain at 2.5 Å. Proteins 1991; 10: 251–9PubMedCrossRefGoogle Scholar
  19. 19.
    Mlsna D, Monzingo AF, Katzin BJ, et al. Structure of recombinant ricin A-chain at 2.3 Å resolution. Protein Sci 1993; 2: 429–35PubMedCrossRefGoogle Scholar
  20. 20.
    Weston SA, Tucker AD, Thatcher DR, et al. X-ray structure of recombinant ricin A-chain at 1.8 Å resolution. J Mol Biol 1994; 244: 410–22PubMedCrossRefGoogle Scholar
  21. 21.
    Monzingo AF, Robertus JD. X-ray analysis of substrate analogs in the ricin A-chain active site. J Mol Biol 1992; 227: 1136–45PubMedCrossRefGoogle Scholar
  22. 22.
    Endo Y, Tsurugi K. RNA N-glycosidase activity of ricin A-chain: mechanism of action of the toxic lectin ricin on eukaryotic ribosomes. J Biol Chem 1987; 262: 8128–30PubMedGoogle Scholar
  23. 23.
    Lewis MS, Youle RJ. Ricin subunit association: thermodynamics and the role of the disulfide bond. J Biol Chem 1986; 261: 11571–7PubMedGoogle Scholar
  24. 24.
    Wright HT, Robertus JD. The intersubunit disulfide bridge of ricin is essential for cytotoxicity. Arch Biochem Biophys 1987; 256: 280–4PubMedCrossRefGoogle Scholar
  25. 25.
    Endo Y, Tsurugi K. The RNA N-glycosidase activity of ricin A-chain. J Biol Chem 1988; 263: 8735–9PubMedGoogle Scholar
  26. 26.
    Wool IG, Correll CC, Yuen-Ling C. Structure and function of the sarcin-ricin domain. In: Garrett J, Douthwaite L, Lilias PJ, et al., editors. The ribosome: structure, function, antibiotics and cellular interactions. Washington, DC: ASM Press, 2000: 461–473Google Scholar
  27. 27.
    Ban N, Nissen P, Hansen J, et al. Placement of protein and RNA structures into a 5Å-resolution map of the 50S ribosomal subunit. Nature 1999; 400: 841–7PubMedCrossRefGoogle Scholar
  28. 28.
    Sperti S, Montanaro L, Mattioli A, et al. Inhibition by ricin of protein synthesis in vitro: 60 S ribosomal subunit as the target of the toxin. Biochem J 1973; 136: 813–5PubMedGoogle Scholar
  29. 29.
    Nilsson L, Nygard O. The mechanism of the protein synthesis elongation cycle in eukaryotes: effect of ricin on the ribosome interaction with elongation factors. Eur J Biochem 1986; 161: 111–7PubMedCrossRefGoogle Scholar
  30. 30.
    Hartley MR, Legname G, Osborn R, et al. Single-chain ribosome-inactivating proteins from plants depurinate Escherichia coli 23S ribosomal RNA. FEBS Lett 1991; 290: 65–8PubMedCrossRefGoogle Scholar
  31. 31.
    Cawley DB, Hedbolm ML, Hoffman EJ, et al. Differential sensitivity of rat liver and wheat germ ribosomes to inhibition of polyuridylic acid translation by ricin A chain. Arch Biochem Biophys 1977; 182: 690–5PubMedCrossRefGoogle Scholar
  32. 32.
    Schlossmann D, Withers D, Welsh P, et al. Role of glutamic acid 177 of the ricin toxin A chain in enzymatic inactivation of ribosomes. Mol Cell Biol 1989; 9: 5012–21Google Scholar
  33. 33.
    Frankel A, Welsh P, Richardson J, et al. Role of arginine 180 and glutamic acid 177 of ricin toxin A chain in enzymatic inactivation of ribosomes. Mol Cell Biol 1990 Dec; 10: 6257–63PubMedGoogle Scholar
  34. 34.
    Ready MP, Kim Y, Robertus JD. Site-directed mutagenesis of ricin A-chain and implications for the mechanism of action. Proteins 1991; 10: 270–8PubMedCrossRefGoogle Scholar
  35. 35.
    Kim Y, Robertus JD. Analysis of several active site resiues of ricin A chain by mutagenesis and x-ray crystallography. Protein Eng 1992; 5: 775–9PubMedCrossRefGoogle Scholar
  36. 36.
    Chaddock JA, Roberts LM. Mutagenesis and kinetic analysis of the active site Glu177 of ricin A-chain. Protein Eng 1993; 6: 425–31PubMedCrossRefGoogle Scholar
  37. 37.
    Barbieri L, Valbonesi P, Bonora E, et al. Polynucleotide: adenosine glycosidase activity of ribosome-inactivating proteins: effect on DNA, RNA and poly A. Nucleic Acids Res 1997; 25: 518–22PubMedCrossRefGoogle Scholar
  38. 38.
    Brigotti M, Alfies R, Sestili P, et al. Damage to nuclear DNA induced by Shiga toxin 1 and ricin in human endothelial cells. FASEB J 2002; 16: 365–72PubMedCrossRefGoogle Scholar
  39. 39.
    Komatsu N, Oda T, Muramatsu T. Involvement of both caspase-like proteases and serine proteases in apoptotic cell death induced by ricin, modeccin, diphtheria toxin and Pseudomonas toxin. J Biochem (Tokyo) 1998; 124: 1038–44CrossRefGoogle Scholar
  40. 40.
    Hu R, Zhai Q, Liu W, et al. An insight into the mechanism of cytotoxicity of ricin to hepatoma cells: roles of Bcl-2 family proteins, caspases, Ca2+-dependent proteases and protein kinase C. J Cell Biochem 2001; 81: 583–93PubMedCrossRefGoogle Scholar
  41. 41.
    Barbieri L, Valbonesi P, Righi F, et al. Polynucleotide: adenosine glycosidase is the sole activity of ribosome-inactivating proteins on DNA. J Biochem (Tokyo) 2000; 128: 883–9CrossRefGoogle Scholar
  42. 42.
    Day PJ, Lord JM, Roberts LM. The deoxyribonuclease activity attributed to ribosome-inactivating proteins is due to contamination. Eur J Biochem 1999; 258: 540–5CrossRefGoogle Scholar
  43. 43.
    van Damme EJM, Hao Q, Chen Y, et al. Ribosome-inactivating proteins: a family of plant proteins that do more than inactivate ribosomes. Crit Rev Plant Sci 2001; 20: 395–465Google Scholar
  44. 44.
    Barbieri L, Valbonesi P, Bonora E. Polynucleotide:adenosine glycosidase activity of ribosome-inactivating proteins: effect on DNA, RNA and poly A. Nucleic Acids Res 1997; 25: 519–22CrossRefGoogle Scholar
  45. 45.
    Morlon-Guyot J, Helmy M, Lombard-Frasca S, et al. Ricin lipase activity: identification of the catalytic site and implication in cytotoxicity. J Biol Chem 2003; 278: 17006–11PubMedCrossRefGoogle Scholar
  46. 46.
    Lord JM, Roberts LM, Robertus JD. Ricin: structure, mode of action, and some current applications. FASEB J 1994; 8: 201–8PubMedGoogle Scholar
  47. 47.
    Butterworth AG, Lord JM. Ricin and Ricinus communis agglutinin subunits are all derived from a single-size polypeptide precursor. Eur J Biochem 1983; 137: 57–65PubMedCrossRefGoogle Scholar
  48. 48.
    Ferrini JB, Martin M, Taupiac MP, et al. Expression of functional ricin B chain using the baculovirus system. Eur J Biochem 1995; 233: 772–7PubMedCrossRefGoogle Scholar
  49. 49.
    Lamb FI, Roberts LM, Lord JM. Nucleotide sequence of cloned cDNA coding for preproricin. Eur J Biochem 1985; 148: 265–70PubMedCrossRefGoogle Scholar
  50. 50.
    Lord JM. Precursors of ricin and Ricinus communis agglutinin: glycosylation and processing during synthesis and intracellular transport. Eur J Biochem 1985; 146: 411–6PubMedCrossRefGoogle Scholar
  51. 51.
    Roberts LM, Lord JM. The synthesis of Ricinus communis agglutinin. Eur J Biochem 1981; 119: 31–4PubMedCrossRefGoogle Scholar
  52. 52.
    Lord JM. Synthesis and intracellular transport of lectin and storage protein precursors in endosperm from castor bean. Eur J Biochem 1985; 146: 403–9PubMedCrossRefGoogle Scholar
  53. 53.
    Lord JM, Harley SM. Ricinus communis agglutinin B chain contains a fucosylated oligosaccharide side chain not present on ricin B chain. FEBS Lett 1985: 189; 72–6CrossRefGoogle Scholar
  54. 54.
    Harley SM, Lord JM. In vitro endoproteolytic cleavage of castor bean lectin precursors. Plant Sci 1985; 41: 111–6CrossRefGoogle Scholar
  55. 55.
    Frigerio L, Vitale A, Lord JM, et al. Free ricin A chain, proricin and native toxin have different cellular fates when expressed in tobacco protoplasts. J Biol Chem 1998; 273: 14194–9PubMedCrossRefGoogle Scholar
  56. 56.
    Frigerio L, Jolliffe NA, Di Cola A, et al. The internal propeptide of the ricin precursor carries a sequence-specific determinant for vacuolar sorting. Plant Physiol 2001; 126: 167–75PubMedCrossRefGoogle Scholar
  57. 57.
    Jolliffe NA, Ceriotti A, Frigerio L, et al. The position of the proricin vacuolar targeting signal is functionally important. Plant Mol Biol 2003; 41: 825–35Google Scholar
  58. 58.
    Richardson PT, Westby M, Roberts LM, et al. Recombinant proricin binds galactose but does not depurinate 28S ribosomal RNA. FEBS Lett 1989; 255: 15–20PubMedCrossRefGoogle Scholar
  59. 59.
    Harley SM, Beevers H. Ricin inhibition of in vivo protein synthesis by plant ribosomes. Proc Natl Acad Sci U S A 1982; 79: 5935–8PubMedCrossRefGoogle Scholar
  60. 60.
    Taylor S, Massiah A, Lomonossoff G, et al. Correlation between the activities of five ribosome-inactivating proteins in depurination of tobacco ribosomes and inhibition of tobacco mosaic virus infection. Plant J 1994; 5: 827–35PubMedCrossRefGoogle Scholar
  61. 61.
    Sandvig K, Olsnes S, Pihl A. Kinetics of binding of the toxic lectins abrin and ricin to surface receptors of human cells. J Biol Chem 1976; 251: 3977–84PubMedGoogle Scholar
  62. 62.
    Spilsberg B, van Meer G, Sandvig K. Role of lipids in the retrograde pathway of ricin intoxication. Traffic 2003; 4: 544–52PubMedCrossRefGoogle Scholar
  63. 63.
    Simmons BM, Stahl PD, Russell JH. Mannose receptor-mediated uptake of ricin toxin and ricin A chain by macrophages: multiple intracellular pathways for A chain translocation. J Biol Chem 1986; 261: 7912–20PubMedGoogle Scholar
  64. 64.
    Magnusson S, Kjeken R, Berg T. Characterization of two distinct pathways of endocytosis of ricin by rat liver endothelial cells. Exp Cell Res 1993; 205: 118–25PubMedCrossRefGoogle Scholar
  65. 65.
    Sandvig K, van Deurs B. Endocytosis, intracellular transport, and cytotoxic action of Shiga toxin and ricin. Physiol Rev 1996; 76: 949–66PubMedGoogle Scholar
  66. 66.
    Sandvig K, van Deurs B. Entry of ricin and Shiga toxin into cells: molecular mechanisms and medical perspectives. EMBO J 2000; 19: 5943–50PubMedCrossRefGoogle Scholar
  67. 67.
    Iversen TG, Skretting G, Llorente A, et al. Endosome to Golgi transport of ricin is independent of clathrin and of the Rab9- and Rab11-GTPases. Mol Biol Cell 2001; 12: 2099–107PubMedGoogle Scholar
  68. 68.
    van Deurs B, Petersen OW, Sundan A, et al. receptor-mediated endocytosis of a ricin-colloidal gold conjugate in Vero cells: intracellular routing to vacuolar and tubulo-vesicular portions of the endosomal system. Exp Cell Res 1985; 159: 287–304PubMedCrossRefGoogle Scholar
  69. 69.
    Moya M, Dautry-Varsat A, Goud B, et al. Inhibition of coated pit formation in Hep2 cells blocks the cytotoxicity of diphtheria toxin but not that of ricin toxin. J Cell Biol 1985; 101: 548–59PubMedCrossRefGoogle Scholar
  70. 70.
    Simpson JC, Smith DC, Roberts LM, et al. Expression of mutant dynamin protects cells against diphtheria toxin but not against ricin. Exp Cell Res 1998; 239: 293–300PubMedCrossRefGoogle Scholar
  71. 71.
    Llorente A, Rapak A, Schmid SL, et al. Expression of mutant dynamin inhibits toxicity and transport of endocytosed ricin to the Golgi apparatus. J Cell Biol 1998; 140: 553–63PubMedCrossRefGoogle Scholar
  72. 72.
    Nichols BJ, Lippincott-Schwartz J. Endocytosis without clathrin coats. Trends Cell Biol 2001; 11: 406–12PubMedCrossRefGoogle Scholar
  73. 73.
    Rodal SK, Skretting G, Garred O, et al. Extraction of cholesterol with methyl-beta-cyclodextrin perturbs formation of clathrin-coated endocytic vesicles. Mol Biol Cell 1999; 10: 961–74PubMedGoogle Scholar
  74. 74.
    Herskovits JS, Burgess CC, Obar RA, et al. Effects of mutant rat dynamin on endocytosis. J Cell Biol 1993; 122: 565–78PubMedCrossRefGoogle Scholar
  75. 75.
    van der Bliek AM, Redelmeier TE, Damke H, et al. Mutations in human dynamin block an intermediate stage in coated vesicle formation. J Cell Biol 1993; 122: 553–63PubMedCrossRefGoogle Scholar
  76. 76.
    Artalejo CR, Henley JR, McNiven MA, et al. Rapid endocytosis coupled to exocytosis in adrenal chromaffin cells involves Ca2+, GTP, and dynamin but not clathrin. Proc Natl Acad Sci U S A 1995; 92: 8328–32PubMedCrossRefGoogle Scholar
  77. 77.
    Damke H, Baba T, van der Bliek AM, et al. Clathrin-independent pinocytosis is induced in cells overexpressing a temperature-sensitive mutant of dynamin. J Cell Biol 1995; 131: 69–80PubMedCrossRefGoogle Scholar
  78. 78.
    Werbonat Y, Kleutges N, Jakobs KH, et al. Essential role of dynamin in internalization of M2 muscarinic acetylcholine and angiotensin AT1A receptors. J Biol Chem 2000; 275: 21969–74PubMedCrossRefGoogle Scholar
  79. 79.
    Lamaze C, Dujeancourt A, Baba T, et al. Interleukin-2 receptors and detergent-resistant membrane domains define a chlathrin-independent endocytic pathway. Mol Cell 2001; 7: 661–71PubMedCrossRefGoogle Scholar
  80. 80.
    Ray B, Wu HC. Internalization of ricin in chinese hamster ovary cells. Mol Cell Biol 1981; 1: 544–51PubMedGoogle Scholar
  81. 81.
    van Deurs B, Petersen OW, Olsnes S, et al. The ways of endocytosis. Int Rev Cytol 1989; 117: 131–77PubMedCrossRefGoogle Scholar
  82. 82.
    Scherer PE, Tang Z, Chun M, et al. Caveolin isoforms differ in their N-terminal protein sequence and subcellular distribution. J Biol Chem 1995; 270: 16395–401PubMedCrossRefGoogle Scholar
  83. 83.
    van Deurs B, Sandvig K, Petersen OW, et al. Estimation of the amount of internalized ricin that reaches the trans-Golgi network. J Cell Biol 1988; 106: 53–67Google Scholar
  84. 84.
    Rapak A, Falnes PO, Olsnes S. Retrograde transport of mutant ricin to the endoplasmic reticulum with subsequent translocation to cytosol. Proc Natl Acad Sci U S A 1997; 94: 783–8CrossRefGoogle Scholar
  85. 85.
    Ghosh RN, Mallet WG, Soe TT, et al. An endocytosed TGN38 chimeric protein is delivered to the TGN after trafficking through the endocytic recycling compartment in CHO cells. J Cell Biol 1998; 142: 923–36PubMedCrossRefGoogle Scholar
  86. 86.
    Mallard F, Antony C, Tenza D, et al. Direct pathway from early/recycling endosomes to the Golgi apparatus revealed through the study of shiga toxin B-fragment transport. J Cell Biol 1998; 143: 973–90PubMedCrossRefGoogle Scholar
  87. 87.
    Mallet WG, Maxfield FR. Chimeric forms of furin and TGN38 are transported with the plasma membrane in the trans-Golgi network via distinct endosomal pathways. J Cell Biol 1999; 146: 345–59PubMedCrossRefGoogle Scholar
  88. 88.
    Sandvig K, Grimmer S, Lauvrak SU, et al. Pathways followed by ricin and Shiga toxin into cells. Histochem Cell Biol 2002; 117: 131–41PubMedCrossRefGoogle Scholar
  89. 89.
    Lombardi D, Soldati T, Riederer MA, et al. Rab9 functions in the transport between late endosomes and the trans-Golgi network. EMBO J 1993; 12: 677–82PubMedGoogle Scholar
  90. 90.
    Riederer MA, Soldati T, Shapiro AD, et al. Lysosome biogenesis requires Rab9 function and receptor recycling from late endosomes to the trans-Golgi network. J Cell Biol 1994; 125: 573–82PubMedCrossRefGoogle Scholar
  91. 91.
    Clague MJ, Urbe S, Aniento F, et al. Vacuolar ATPase activity is required for endosomal carrier vesicle formation. J Biol Chem 1994; 269: 21–4PubMedGoogle Scholar
  92. 92.
    Melby EL, Prydz K, Olsnes S, et al. Effect of monensin on ricin and fluid phase transport in polarized MDCK cells. J Cell Biochem 1991; 47: 251–60PubMedCrossRefGoogle Scholar
  93. 93.
    Mallard F, Tang BL, Galli T, et al. Early/recycling endosomes-to-TGN transport involves two SNARE complexes and a Rab6 isoform. J Cell Biol 2002; 156: 653–64PubMedCrossRefGoogle Scholar
  94. 94.
    Johannes L. The epithelial cell cytoskeleton and intracellular trafficking: 1 Shiga toxin B-subunit system, retrograde transport, intracellular vectorization, and more. Am J Physiol Gastroint Liver Physiol 2002; 283: G1–7Google Scholar
  95. 95.
    Grimmer S, Iversen TG, van Deurs B, et al. Endosome to Golgi transport of ricin is regulated by cholesterol. Mol Biol Cell 2000; 11: 4205–16PubMedGoogle Scholar
  96. 96.
    Birkeli KA, Llorente A, Torgersen ML, et al. Endosome-to-Golgi transport is regulated by protein kinase A type II alpha. J Biol Chem 2003; 278: 1991–7PubMedCrossRefGoogle Scholar
  97. 97.
    van Deurs B, Tonnessen TI, Peterson OW, et al. Routing of internalised ricin and ricin conjugates to the Golgi complex. J Cell Biol 1986; 102: 37–47PubMedCrossRefGoogle Scholar
  98. 98.
    Yoshida T, Chen C, Zhang M, et al. Disruption of the Golgi apparatus by brefeldin A inhibits the cytotoxicity of ricin, modeccin and Pseudomonas toxin. Exp Cell Res 1991; 192: 389–95PubMedCrossRefGoogle Scholar
  99. 99.
    Prydz K, Hansen SH, Sandvig K, et al. Effects of brefeldin A on endocytosis, transcytosis and transport to the Golgi complex in polarized MDCK cells. J Cell Biol 1992; 119: 259–72PubMedCrossRefGoogle Scholar
  100. 100.
    Okimoto T, Seguchi T, Ono M, et al. Brefeldin A protects ricin-induced cytotoxicity in human cancer KB cell line, but not in its resistant counterpart with altered Golgi structures. Cell Struct Funct 1993; 18: 241–51PubMedCrossRefGoogle Scholar
  101. 101.
    Boman AL, Kahn RA. Arf proteins: the membrane traffic police? Trends Biochem Sci 1995; 20: 147–50PubMedCrossRefGoogle Scholar
  102. 102.
    Helms JB, Rothman JE. Inhibition by brefeldin A of a Golgi membrane enzyme that catalyses exchange of guanine nucleotide bound to ARF. Nature 1992; 360: 352–4PubMedCrossRefGoogle Scholar
  103. 103.
    Klausner RD, Donaldson JG, Lippincott-Schwartz J. Brefeldin A: insights into the control of membrane traffic and organelle structure. J Cell Biol 1992; 116: 1071–80PubMedCrossRefGoogle Scholar
  104. 104.
    Namibar MP, Wu HC. Ilimaquinone inhibits the cytotoxicities of ricin, diphtheria toxin, and other protein toxins in Vero cells. Exp Cell Res 1995; 219: 671–8CrossRefGoogle Scholar
  105. 105.
    Simpson JC, Dascher C, Roberts LM, et al. Ricin cytotoxicity is sensitive to recycling between the endoplasmic reticulum and the Golgi complex. J Biol Chem 1995; 270: 20078–83PubMedCrossRefGoogle Scholar
  106. 106.
    Wales R, Chaddock JA, Roberts LM, et al. Addition of an ER retention signal to the ricin A chain increases the cytotoxicity of the holotoxin. Exp Cell Res 1992; 203: 1–4PubMedCrossRefGoogle Scholar
  107. 107.
    Wesche J, Rapak A, Olsnes S. Dependence of ricin toxicity on translocation of the toxin A-chain from the endoplasmic reticulum to the cytosol. J Biol Chem 1999; 274: 34443–9PubMedCrossRefGoogle Scholar
  108. 108.
    Wales R, Roberts LM, Lord JM. Addition of an endoplasmic reticulum retrieval sequence to ricin A chain significantly increase its cytotoxicity to mammalian cells. J Biol Chem 1993; 268: 23986–90PubMedGoogle Scholar
  109. 109.
    Zhan J, Stayton P, Press OW. Modification of ricin A chain, by addition of endoplasmic reticulum (KDEL) or Golgi (YQRL) retention sequences, enhances its cytotoxicity and translocation. Cancer Immunol Immunother 1998; 46: 55–60PubMedCrossRefGoogle Scholar
  110. 110.
    Sandvig K, van Deurs B. Selective modulation of the endocytic uptake of ricin and fluid phase markers without alteration in transferring endocytosis. J Biol Chem 1990; 265: 6382–8PubMedGoogle Scholar
  111. 111.
    Day PJ, Owens SR, Wesche J, et al. An interaction between ricin and calreticulin that may have implications for toxin trafficking. J Biol Chem 2001; 276: 7202–8PubMedCrossRefGoogle Scholar
  112. 112.
    Cosson P, Letourneur F. Coatomer interaction with di-lysine endoplasmic reticulum retention motifs. Science 1994; 263: 1629–31PubMedCrossRefGoogle Scholar
  113. 113.
    Cosson P, Letourneur F. Coatomer (COP1)-coated vesicles: role in intracellular transport and protein sorting. Curr Opin Cell Biol 1997; 7: 484–7CrossRefGoogle Scholar
  114. 114.
    Girod A, Storrie B, Simpson JC, et al. Evidence for a COP1-independent transport route from the Golgi complex to the endoplasmic reticulum. Nat Cell Biol 1999; 1: 423–30PubMedCrossRefGoogle Scholar
  115. 115.
    White J, Johannes L, Mallard F, et al. Rab6 coordinates a novel Golgi to ER retrograde transport pathway in live cells. J Cell Biol 1999; 147: 743–59PubMedCrossRefGoogle Scholar
  116. 116.
    Chaudhary V, Jinno Y, FitzGerald D, et al. Pseudomonas exotoxin contains a specific sequence at the carboxyl terminus that is required for cytotoxicity. Proc Natl Acad Sci U S A 1990; 87: 308–12PubMedCrossRefGoogle Scholar
  117. 117.
    Lencer WI, Constable C, Moe S, et al. Targeting of cholera toxin and Escherichia coli heat labile toxin in polarized epithelia: role of COOH-terminal KDEL. J Cell Biol 1995; 131: 951–62PubMedCrossRefGoogle Scholar
  118. 118.
    Majoul I, Sohn K, Wieland FT, et al. KDEL receptor (Erd2p)-mediated retrograde transport of the cholera toxin A subunit from the Golgi involves COP1, p23, and the COOH-terminus of Erd2p. J Cell Biol 1998; 143: 601–12PubMedCrossRefGoogle Scholar
  119. 119.
    Jackson ME, Simpson JC, Girod A, et al. The KDEL retrieval system is exploited by Pseudomonas exotoxin A, but not by Shiga-like toxin-1, during retrograde transport from the Golgi complex to the endoplasmic reticulum. J Cell Sci 1999; 112: 467–75PubMedGoogle Scholar
  120. 120.
    Chen A, Hu T, Mikoryak C, et al. Retrograde transport of protein toxins under conditions of COPI disfunction. Biochim Biophys Acta 2002; 1589: 124–39PubMedCrossRefGoogle Scholar
  121. 121.
    Beaumelle B, Alami M, Hopkins CR. ATP-dependent translocation of ricin across the membrane of purified endosomes. J Biol Chem 1993; 268: 23661–9PubMedGoogle Scholar
  122. 122.
    Pelham HRB, Roberts LM, Lord JM. Toxin entry: how reversible is the secretory pathway? Trends Cell Biol 1992; 2: 183–5PubMedCrossRefGoogle Scholar
  123. 123.
    Johnson AE, van Waes MA. The translocon: a dynamic gateway at the ER membrane. Annu Rev Cell Dev Biol 1999; 15: 799–842PubMedCrossRefGoogle Scholar
  124. 124.
    Russ G, Esquivel F, Yewdell JW, et al. Assembly, intracellular localization and nucleotide binding properties of the human peptide transporters TAP1 and TAP2 expressed by recombinant vaccinia viruses. J Biol Chem 1995; 270: 312–24Google Scholar
  125. 125.
    Ivessa NE, Kitzmuller C, de Virgilio M. ER-associated protein degradation inside and outside of the endoplasmic reticulum. Protoplasma 1999; 207: 16–23CrossRefGoogle Scholar
  126. 126.
    Brodsky JL, McCracken AA. ER protein quality control and proteasome-mediated protein degradation. Semin Cell Dev Biol 1999; 10: 507–13PubMedCrossRefGoogle Scholar
  127. 127.
    Tsai B, Ye Y, Rapoport TA. Retro-translocation of proteins from the endoplasmic reticulum to the cytosol. Nat Rev Mol Cell Biol 2002; 3: 246–55PubMedCrossRefGoogle Scholar
  128. 128.
    Jarosch E, Geiss-Friedlander R, Meusser B, et al. Protein dislocation from the endoplasmic reticulum: pulling out the suspect. Traffic 2002; 3: 530–6PubMedCrossRefGoogle Scholar
  129. 129.
    Orlandi PA. Protein disulfide isomerase reduction of the A subunit of cholera toxin in a human intestinal cell line. J Biol Chem 1997; 272: 4591–9PubMedGoogle Scholar
  130. 130.
    Majoul I, Ferrari D, Söling HD. Reduction of protein disulfide bonds in an oxidizing environment: the disulfide bridge of cholera toxin A subunit is reduced in thye endoplasmic reticulum. FEBS Lett 1997; 401: 104–8PubMedCrossRefGoogle Scholar
  131. 131.
    Tsai B, Rapoport TA. Unfolded cholera toxin is transferred to the ER membrane and released from protein disulfide isomerase upon oxidation by Ero1. J Cell Biol 2002; 159: 207–15PubMedCrossRefGoogle Scholar
  132. 132.
    McKee ML, FitzGerald DJ. Reduction of furin-nicked Pseudomonas exotoxin A: an unfolding story. Biochemistry 1999; 38: 16507–5513PubMedCrossRefGoogle Scholar
  133. 133.
    Mohanraj D, Ramakrishnan D. Cytotoxic effects of ricin without an interchain disulfide bond: genetic modification and chemical crosslinking studies. Biochim Biophys Acta 1995; 1243: 399–406PubMedCrossRefGoogle Scholar
  134. 134.
    Day PJ, Pinheiro TJT, Roberts LM, et al. Binding of ricin A chain to negatively charged phospholipid vesicles leads to protein structural changes and destabilizes the lipid bilayer. Biochemistry 2002; 41: 2836–43PubMedCrossRefGoogle Scholar
  135. 135.
    Tsai B, Rodighero C, Lencer WI, et al. Protein disulfide isomerase acts as a redox-dependent chaperone to unfold cholera toxin. Cell 2001; 104: 937–48PubMedCrossRefGoogle Scholar
  136. 136.
    Teter K, Holmes RK. Inhibition of endoplasmic reticulum-associated degradation in CHO cells resistant to cholera toxin, Pseudomonas aeruginosa exotoxin A, and ricin. Infect Immun 2002; 70: 6172–9PubMedCrossRefGoogle Scholar
  137. 137.
    Hazes B, Read RJ. Accumulating evidence suggests that several A-B toxins subvert the endoplasmic reticulum-associated protein degradation pathway to enter target cells. Biochemistry 1997; 36: 11051–4PubMedCrossRefGoogle Scholar
  138. 138.
    Deeks ED, Cook JP, Day PJ, et al. The low lysine content of ricin A chain reduces the risk of proteolytic degradation after translocation from the endoplasmic reticulum to the cytosol. Biochemistry 2002; 41: 3405–13PubMedCrossRefGoogle Scholar
  139. 139.
    Rodighiero C, Tsai B, Rapoport TA, et al. Role of ubiquitination in retro-translocation of cholera toxin and escape of cytosolic degradation. EMBO Rep 2002; 3: 1222–7PubMedCrossRefGoogle Scholar
  140. 140.
    Argent RH, Parrott AW, Day PJ, et al. Ribosome-mediated folding of partially unfolded ricin A chain. J Biol Chem 2000; 275: 9263–9PubMedCrossRefGoogle Scholar
  141. 141.
    Frankel A, Schlossman D, Welsh P, et al. Selection and characterisation of ricin toxin A-chain mutations in Saccharomyces cerevisiae. Mol Cell Biol 1989; 9: 415–20PubMedGoogle Scholar
  142. 142.
    Pilon M, Shekman R, Römisch K, et al. Sec61p mediates export of a misfolded secretory protein from the endoplasmic reticulum to the cytosol for degradation. EMBO J 1997; 16: 4540–8PubMedCrossRefGoogle Scholar
  143. 143.
    Plemper RK, Böhmler S, Bordallo J, et al. Mutant analysis links to the translocon and BiP to retrograde protein transport for ER degradation. Nature 1997; 388: 891–5PubMedCrossRefGoogle Scholar
  144. 144.
    Simpson JC, Roberts LM, Römisch K, et al. Ricin A chain utilises the endoplasmic reticulum-associated protein degradation pathway to enter the cytosol of yeast. FEBS Lett 1999; 459: 80–4PubMedCrossRefGoogle Scholar
  145. 145.
    Vashist S, Kim W, Belden WJ, et al. Distinct retrieval and retention mechanisms are required for the quality control of endoplasmic reticulum protein folding. J Cell Biol 2001; 155: 355–68PubMedCrossRefGoogle Scholar
  146. 146.
    Caldwell SR, Hill KJ, Cooper AA. Degradation of endoplasmic reticulum (ER) quality control substrates requires transport between the ER and Golgi. J Biol Chem 2001; 276: 23296–303PubMedCrossRefGoogle Scholar
  147. 147.
    Smallshaw JE, Ghetie V, Rizo J, et al. Genetic engineering of an immunotoxin to eliminate pulmonary vascular leak in mice. Nat Biotechnol 2003 Apr; 21(4): 387–91PubMedCrossRefGoogle Scholar
  148. 148.
    Tommasi M, Castelletti D, Pasti M, et al. Identification of ricin A chain HLA class II-restricted epitopes by human T cell clones. Clin Exp Immunol 2001; 125: 391–400PubMedCrossRefGoogle Scholar
  149. 149.
    Smallshaw JE, Firan A, Fulmer TR, et al. A novel recombinant vaccine which protects mice against ricin intoxication. Vaccine 2002; 20: 3422–7PubMedCrossRefGoogle Scholar

Copyright information

© Adis Data Information BV 2003

Authors and Affiliations

  • Michael J. Lord
    • 1
  • Nicholas A. Jolliffe
    • 1
  • Catherine J. Marsden
    • 1
  • Cassandra S. C. Pateman
    • 1
  • Daniel C. Smith
    • 1
  • Robert A. Spooner
    • 1
  • Peter D. Watson
    • 1
  • Lynne M. Roberts
    • 1
  1. 1.Department of Biological SciencesUniversity of WarwickCoventryUK

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