Axel H. Schönthal

Department of Molecular Microbiology and Immunology, K. Norris Jr. Comprehensive Cancer Center, University of Southern California, 2011 Zonal Ave., HMR-405, Los Angeles, CA 90033

Received 8/25/98 Accepted 12/2/98

9. REFERENCES

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12. Schönthal, A.: Okadaic acid: A valuable new tool to study signal transduction and cell cycle regulation? New Biologist 4, 16-21 (1992)

13. Cohen, P. T. W., M. X. Chen & C. G. Armstrong: Novel protein phosphatases that may participate in cell signaling. In: H. Hidaka and A. C. Nairn (eds.), Advances in Pharmacology: Intracellular Signal Transduction, Vol. 36, pp. 67-89. Boston: Academic Press (1996)

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18. Honkanen, R. E., J. Zwiller, S. L. Daily, B. S. Khatra, M. Dukelow & A. L. Boynton: Identification, purification, and characterization of a novel serine/threonine protein phosphatase from bovine brain. J. Biol. Chem. 266, 6614-6619 (1991)

19. Brewis, N. D., A. J. Street, A. R. Prescott & P. T. W. Cohen: PPX, a novel protein serine/threonine phosphatase localized to centrosomes. EMBO J. 12, 987-996 (1993)

20. Chen, M. X., A. E. McPartlin, L. Brown, Y. H. Chen, H. M. Barker & P. T. W. Cohen: A novel human protein serine/threonine phosphatase, which possesses four tetratricopeptide repeat motifs and localizes to the nucleus. EMBO J. 13, 4278-4290 (1994)

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23. Fiscella, M., H. Zhang, S. Fan, K. Sakaguchi, S. Shen, W. E. Mercer, G. F. Vande Woude, P. M. O'Connor & E. Appella: Wip1, a novel human protein phosphatase that is induced in response to ionizing radiation in a p53-dependent manner. Proc. Natl. Acad. Sci. USA 94, 6048-6058 (1997)

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25. Chen, M. X., Y. H. Chen & P. T. W. Cohen: Polymerase chain reactions using Saccharomyces, Drosophila and human DNA predict a larger family of protein serine/threonine phosphatases. FEBS L. 306, 54-58 (1992)

26. Nagao, M., H. Shima, M. Nakayasu & T. Sugimura: Protein serine/threonine phosphatases as binding proteins for okadaic acid. Mutation Res. 333, 173-179 (1995)

27. Bagu, J. R., B. D. Sykes, M. M. Craig & C. F. Holmes: A molecular basis for different interactions of marine toxins with protein phosphatase-1. Molecular models for bound motuporin, microcystins, okadaic acid, and calyculin A. J. Biol. Chem. 272, 5087-5097 (1997)

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29. Schönthal, A. H.: Analyzing gene expression with the use of serine/threonine phosphatase inhibitors. In: J. W. Ludlow (ed.) Methods in Molecular Biology: Protein Phosphatase Protocols, Vol. 93, pp. 35-40. Totowa, N.J.: Humana Press (1998)

30. Cohen, P., S. Klumpp & D. L. Schelling: An improved procedure for identifying and quantitating protein phosphatases in mammalian tissues. FEBS L. 250, 596-600 (1989)

31. Honkanen, R. E., B. A. Codispoti, K. Tse & A. L. Boynton: Characterization of natural toxins with inhibitory activity against serine/threonine protein phosphatases. Toxicon 32, 339-350 (1994)

32. Honkanen, R. E., M. Dukelow, J. Zwiller, R. E. Moore, B. S. Khatra & A. L. Boynton: Cyanobacterial nodularin is a potent inhibitor of type 1 and type 2A protein phosphatases. Mol. Pharmacol. 40, 577-583 (1991)

33. Takai, A., K. Sasaki, H. Nagai, G. Mieskes, M. Isobe, K. Isono & T. Yasumoto: Inhibition of specific binding of okadaic acid to protein phosphatase 2A by microcystin-LR, calyculin A and tautomycin. Biochem. J. 306, 657-665 (1995)

34. MacKintosh, C., K. A. Beattie, S. Klumpp, P. Cohen & G. A. Codd: Cyanobacterial microcystin-LR is a potent and specific inhibitor of protein phosphatases 1 and 2A from both mammals and higher plants. Fed. Eur. Biochem. Soc. Lett. 264, 187-192 (1990)

35. Honkanen, R. E., J. Zwiller, R. E. Moore, S. L. Daily, B. S. Khatra, M. Dukelow & A. L. Boynton: Characterization of microcystin-LR, a potent inhibitor of type 1 and type 2A protein phosphatases. J. Biol. Chem. 265, 19401-19404 (1990)

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37. Suganuma, M., S. Okabe, E. Sueoka, R. Nishiwaki, A. Komori, N. Uda, K. Isono & H. Fujiki: Tautomycin: an inhibitor of protein phosphatases 1 and 2A but not a tumor promoter on mouse skin and in rat glandular stomach. J. Cancer Res. Clin. Oncol. 121, 621-627 (1995)

38. Fukuda, H., H. Shima, R. F. Vesonder, H. Tokuda, H. Nishio, S. Katoh, S. Tamura, T. Sugimura & M. Nagao: Inhibition of protein serine/threonine phosphatases by fumonisin B1, a mycotoxin. Biochem. Biophys. Res. Comm. 220, 160-165 (1996)

39. Li, Y. M. & J. E. Casida: Cantharidin-binding protein: identification as protein phosphatase 2A. Proc. Nat. Acad. Sci. USA 89, 11867-11870 (1992)

40. Honkanen, R. E.: Cantharidin, another natural toxin that inhibits the activity of serine/threonine protein phosphatases types 1 and 2A. Fed. Eur. Biochem. Soc. Lett. 330, 283-286 (1993)

41. Matsuzawa, S., T. Suzuki, M. Suzuki, A. Matsuda, T. Kawamura, Y. Mizuno & K. Kikuchi: Thyrsiferyl 23-acetate is a novel specific inhibitor of protein phosphatase PP2A. Fed. Eur. Biochem. Soc. Lett. 356, 272-274 (1994)

42. Craig, M., H. A. Luu, T. L. McCready, D. Williams, R. J. Anderson & C. F. Holmes: Molecular mechanisms underlying he interaction of motuporin and microcystins with type-1 and type-2A protein phosphatases. Biochem. Cell Biol. 74, 569-578 (1996)

43. Roberge, M., C. Tudan, S. M. Hung, K. W. Harder, F. R. Jirik & H. Anderson: Antitumor drug fostriecin inhibits the mitotic entry checkpoint and protein phosphatases 1 and 2A. Cancer Res. 54, 6115-6121 (1994)

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46. Jaramillo-Babb, V., J. L. Sugarman, R. Scavetta, S.-J. Wang, N. Berndt, T. L. Born, C. K. Glass & A. H. Schönthal: Positive regulation of cdc2 gene activity by protein phosphatase type 2A. J. Biol. Chem. 271, 5988-5992 (1996)

47. Boritzki, T. J., T. S. Wolfard, J. A. Besserer, R. C. Jackson & D. W. Fry: Inhibition of type II topoisomerase by fostriecin. Biochem. Pharmacol. 37, 4063-4068 (1988)

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49. Ohta, T., E. Sueoka, N. Iida, A. Komori, M. Suganuma, R. Nishiwaki, M. Tatematsu, S. J. Kim, W. W. Carmichael & H. Fujiki: Nodularin, a potent inhibitor of protein phosphatases 1 and 2A, is a new environmental carcinogen in male F344 rat liver. Cancer Res. 54, 6402-6406 (1994)

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63. Schönthal, A., Y. Tsukitani & J. R. Feramisco: Transcriptional and post-transcriptional regulation of c-fos expression by the tumor promoter okadaic acid. Oncogene 6, 423-430 (1991)

64. Schönthal, A., A. S. Alberts, J. A. Frost & J. R. Feramisco: Differential regulation of jun family gene expression by the tumor promoter okadaic acid. New Biologist 3, 977-986 (1991)

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69. Rosenberger, S. F. & G. T. Bowden: Okadaic acid stimulated TRE binding activity in a papilloma producing mouse keratinocyte cell line involves increased AP-1 expression. Oncogene 12, 2301-2308 (1996)

70. Thévenin, C., S. J. Kim & J. H. Kehrl: Inhibition of protein phosphatases by okadaic acid induces AP1 in human T cells. J. Biol. Chem. 266, 9363-9366 (1991)

71. Schönthal, A. H.: Regulation of gene expression by serine/threonine protein phosphatases. Sem. Cancer Biol. 6, 239-248 (1995)

72. Hipskind, R. A., M. Baccarini & A. Nordheim: Transient activation of RAF-1, MEK, and ERK2 coincides kinetically with ternary complex factor phosphorylation and immediate-early gene promoter activity in vivo. Mol. Cell. Biol. 14, 6219-6231 (1994)

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78. Sontag, E., S. Fedorov, C. Kamibayashi, D. Robbins, M. Cobb & M. Mumby: The interaction of SV40 small tumor antigen with protein phosphatase 2A stimulates the MAP kinase pathway and induces cell proliferation. Cell 75, 887-897 (1993)

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90. Sugarman, J. L., A. R. Thompson, R. Scavetta, C. K. Glass & A. H. Schönthal: Differential effects of two types of tumor promoters, okadaic acid and 12-O-tetradecanoyl-phorbol-13-acetate, on growth and differentiation of human myeloid leukemia cells. Mol. Cell. Diff. 3, 51-71 (1995)

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106. Zheng, B., T. C. Chambers, R. L. Raynor, P. N. Markham, H. M. Gebel, W. R. Vogler & J. F. Kuo: Human leukemia K562 cell mutant (K562/OA200) selected for resistance to okadaic acid (protein phosphatase inhibitor) lacks protein kinase C-, exhibits multidrug resistance phenotype, and expresses drug pump P-glycoprotein. J. Biol. Chem. 269, 12332-12338 (1994)

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108. Ritz, V., J. Marwitz, E. Richter, C. Ziemann, I. Quentin & H. J. Steinfelder: Characterization of two pituitary GH3 cell sublines partially resistant to apoptosis induction by okadaic acid. Biochem. Pharmacol. 54, 967-971 (1997)

109. Chambers, T. C., B. Zheng & J. F. Kuo: Regulation by phorbol ester and protein kinase C inhibitors, and by a protein phosphatase inhibitor (okadaic acid), of P-glycoprotein phosphorylation and relationship to drug accumulation in multidrug-resistant human KB cells. Mol. Pharmacol. 41, 1008-1015 (1992)

110. Tohda, H., M. Takao, A. Kikuchi, T. Yasumoto & A. Yasui: Unstable expression of the multi-drug-resistant phenotype in Chinese hamster ovary cells resistant to okadaic acid. Biochem.Biophys. Res. Comm. 232, 398-402 (1997)

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