Structural basis for ligand regulation of the fatty acidbinding protein 5, peroxisome proliferator-activated receptor β/δ (FABP5-PPARβ/ δ) signaling pathway

Journal of Biological Chemistry

Volumn 289, Issue 21, 2014, Pages 14941-14954

  Armstrong, Eric H ^a   Goswami, Devrishi ^b   Griffin, Patrick R ^b   Noy, Noa ^c   Ortlund, Eric A ^a  

^a EMORY UNIVERSITY SCHOOL OF MEDICINE   (United States)

^b SCRIPPS RESEARCH INSTITUTE   (United States)

^c CASE WESTERN RESERVE UNIVERSITY SCHOOL OF MEDICINE   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

CHEMICAL ACTIVATION; CYTOLOGY; LIGANDS; PIGMENTS; POLYUNSATURATED FATTY ACIDS; PROTEINS;

ALLOSTERIC COMMUNICATION; BIOCHEMICAL TECHNIQUES; CELLULAR FATTY ACIDS; FATTY ACID-BINDING PROTEINS; LONG CHAIN FATTY ACID; NUCLEAR LOCALIZATION SIGNAL; NUCLEAR TRANSLOCATIONS; PEROXISOME PROLIFERATOR-ACTIVATED RECEPTOR;

FATTY ACIDS;

ARACHIDONIC ACID; FATTY ACID BINDING PROTEIN; FATTY ACID BINDING PROTEIN 5; LINOLEIC ACID; PEROXISOME PROLIFERATOR ACTIVATED RECEPTOR DELTA; UNCLASSIFIED DRUG;

ALLOSTERISM; ALPHA HELIX; ARTICLE; CELLULAR DISTRIBUTION; CONTROLLED STUDY; LIGAND BINDING; NUCLEAR LOCALIZATION SIGNAL; OLIGOMERIZATION; PRIORITY JOURNAL; PROTEIN CONFORMATION; PROTEIN STABILITY; SIGNAL TRANSDUCTION; TRANSACTIVATION; X RAY CRYSTALLOGRAPHY;

FATTY ACID; FATTY ACID-BINDING PROTEIN; LIPIDS; NUCLEAR RECEPTORS; POLYUNSATURATED FATTY ACIDS; STRUCTURAL BIOLOGY;

ANIMALS; ARACHIDONIC ACID; BINDING SITES; CELL NUCLEUS; CERCOPITHECUS AETHIOPS; COS CELLS; CYTOPLASM; FATTY ACID-BINDING PROTEINS; FATTY ACIDS; HUMANS; LIGANDS; LINOLEIC ACID; MCF-7 CELLS; MODELS, MOLECULAR; MOLECULAR STRUCTURE; MUTATION; NUCLEAR LOCALIZATION SIGNALS; PPAR GAMMA; PPAR-BETA; PROTEIN BINDING; PROTEIN STRUCTURE, SECONDARY; PROTEIN STRUCTURE, TERTIARY; PROTEIN TRANSPORT; TRANSCRIPTIONAL ACTIVATION;

EID: 84901449113     PISSN: 00219258     EISSN: 1083351X     Source Type: Journal    
DOI: 10.1074/jbc.M113.514646     Document Type: Article

References (75)

1. Göttlicher, M., Widmark, E., Li, Q., and Gustafsson, J. A. (1992) Fatty acids activate a chimera of the clofibric acid-activated receptor and the glucocorticoid receptor. Proc. Natl. Acad. Sci. U.S.A. 89, 4653-4657
2. Banner, C. D., Göttlicher, M., Widmark, E., Sjövall, J., Rafter, J. J., and Gustafsson, J. A. (1993) A systematic analytical chemistry/cell assay approach to isolate activators of orphan nuclear receptors from biological extracts: characterization of peroxisome proliferator-activated receptor activators in plasma. J. Lipid Res. 34, 1583-1591 (Pubitemid 23264331)
3. Amri, E. Z., Bonino, F., Ailhaud, G., Abumrad, N. A., and Grimaldi, P. A. (1995) Cloning of a protein that mediates transcriptional effects of fatty acids in preadipocytes. Homology to peroxisome proliferator-activated receptors. J. Biol. Chem. 270, 2367-2371
4. Forman, B. M., Chen, J., and Evans, R. M. (1997) Hypolipidemic drugs, polyunsaturated fatty acids, and eicosanoids are ligands for peroxisome proliferator-activated receptors α and δ. Proc. Natl. Acad. Sci. U.S.A. 94, 4312-4317 (Pubitemid 27194238)
5. Kliewer, S. A., Sundseth, S. S., Jones, S. A., Brown, P. J., Wisely, G. B., Koble, C. S., Devchand, P., Wahli, W., Willson, T. M., Lenhard, J. M., and Lehmann, J. M. (1997) Fatty acids and eicosanoids regulate gene expression through direct interactions with peroxisome proliferator-activated receptors α and δ. Proc. Natl. Acad. Sci. U.S.A. 94, 4318-4323 (Pubitemid 27194239)
6. Xu, H. E., Lambert, M. H., Montana, V. G., Parks, D. J., Blanchard, S. G., Brown, P. J., Sternbach, D. D., Lehmann, J. M., Wisely, G. B., Willson, T. M., Kliewer, S. A., and Milburn, M. V. (1999) Molecular recognition of fatty acids by peroxisome proliferator-activated receptors. Mol. Cell 3, 397-403 (Pubitemid 29290680)
7. Kersten, S., Desvergne, B., and Wahli, W. (2000) Roles of PPARs in health and disease. Nature 405, 421-424 (Pubitemid 30367411)
8. Willson, T. M., Brown, P. J., Sternbach, D. D., and Henke, B. R. (2000) The PPARs: from orphan receptors to drug discovery. J. Med. Chem. 43, 527-550 (Pubitemid 30127149)
9. Furuhashi, M., and Hotamisligil, G. S. (2008) Fatty acid-binding proteins: role in metabolic diseases and potential as drug targets. Nat. Rev. Drug. Discov. 7, 489-503 (Pubitemid 351767117)
10. Smathers, R. L., and Petersen, D. R. (2011) The human fatty acid-binding protein family: evolutionary divergences and functions. Hum. Genomics 5, 170-191
11. Storch, J., and McDermott, L. (2009) Structural and functional analysis of fatty acid-binding proteins. J. Lipid Res. 50, S126-S131
12. Chmurzyńska, A. (2006) The multigene family of fatty acid-binding proteins (FABPs): function, structure and polymorphism. J. Appl. Genet. 47, 39-48 (Pubitemid 43232158)
13. Ong, D. E., Newcomer, M. E., and Chytil, F. (1994) in The Retinoids: Biology, Chemistry, and Medicine (Sporn, M. B., Roberts, A. B., Goodman, D. S., eds) pp. 288-317, Raven Press, Ltd., New York
14. Storch, J., and Thumser, A. E. (2000) The fatty acid transport function of fatty acid-binding proteins. Biochim. Biophys. Acta 1486, 28-44 (Pubitemid 30336790)
15. Petrescu, A. D., Huang, H., Martin, G. G., McIntosh, A. L., Storey, S. M., Landrock, D., Kier, A. B., and Schroeder, F. (2013) Impact of L-FABP and glucose on polyunsaturated fatty acid induction of PPARα-regulatedβ- oxidative enzymes. Am. J. Physiol. Gastrointest. Liver Physiol. 304, G241-G256
16. Petrescu, A. D., McIntosh, A. L., Storey, S. M., Huang, H., Martin, G. G., Landrock, D., Kier, A. B., and Schroeder, F. (2013) High glucose potentiates L-FABP mediated fibrate induction of PPARα in mouse hepatocytes. Biochim. Biophys. Acta 1831, 1412-1425
17. Hostetler, H. A., McIntosh, A. L., Atshaves, B. P., Storey, S. M., Payne, H. R., Kier, A. B., and Schroeder, F. (2009) L-FABP directly interacts with PPARα in cultured primary hepatocytes. J. Lipid Res. 50, 1663-1675
18. Tan, N. S., Shaw, N. S., Vinckenbosch, N., Liu, P., Yasmin, R., Desvergne, B., Wahli, W., and Noy, N. (2002) Selective cooperation between fatty acid binding proteins and peroxisome proliferator-activated receptors in regulating transcription. Mol. Cell. Biol. 22, 5114-5127 (Pubitemid 34700702)
19. Ayers, S. D., Nedrow, K. L., Gillilan, R. E., and Noy, N. (2007) Continuous nucleocytoplasmic shuttling underlies transcriptional activation of PPARα by FABP4. Biochemistry 46, 6744-6752 (Pubitemid 46906405)
20. Kaczocha, M., Glaser, S. T., and Deutsch, D. G. (2009) Identification of intracellular carriers for the endocannabinoid anandamide. Proc. Natl. Acad. Sci. U.S.A. 106, 6375-6380
21. Kaczocha, M., Vivieca, S., Sun, J., Glaser, S. T., and Deutsch, D. G. (2012) Fatty acid-binding proteins transport N-acylethanolamines to nuclear receptors and are targets of endocannabinoid transport inhibitors. J. Biol. Chem. 287, 3415-3424
22. Siegenthaler, G., Hotz, R., Chatellard-Gruaz, D., Didierjean, L., Hellman, U., and Saurat, J. H. (1994) Purification and characterization of the human epidermal fatty acid-binding protein: localization during epidermal cell differentiation in vivo and in vitro. Biochem. J. 302, 363-371 (Pubitemid 24280086)
23. Marcelino, A. M., Smock, R. G., and Gierasch, L. M. (2006) Evolutionary coupling of structural and functional sequence information in the intracellular lipid-binding protein family. Proteins 63, 373-384
24. Simpson, M. A., LiCata, V. J., Ribarik Coe, N., and Bernlohr, D. A. (1999) Biochemical and biophysical analysis of the intracellular lipid binding proteins of adipocytes. Mol. Cell. Biochem. 192, 33-40 (Pubitemid 29171451)
25. Schug, T. T., Berry, D. C., Shaw, N. S., Travis, S. N., and Noy, N. (2007) Opposing effects of retinoic acid on cell growth result from alternate activation of two different nuclear receptors. Cell 129, 723-733 (Pubitemid 46802374)
26. Maeda, K., Uysal, K. T., Makowski, L., Görgün, C. Z., Atsumi, G., Parker, R. A., Brüning, J., Hertzel, A. V., Bernlohr, D. A., and Hotamisligil, G. S. (2003) Role of the fatty acid binding protein mal1 in obesity and insulin resistance. Diabetes 52, 300-307 (Pubitemid 36173182)
27. Hong, J., Gu, W., Zhang, Y., Yan, Q., Dai, M., Shi, J., Zhai, Y., Wang, W., Li, X., and Ning, G. (2011) Different association of circulating levels of adipocyte and epidermal fatty acid-binding proteins with metabolic syndrome and coronary atherosclerosis in Chinese adults. Atherosclerosis 217, 194-200
28. Yeung, D. C., Wang, Y., Xu, A., Cheung, S. C., Wat, N. M., Fong, D. Y., Fong, C. H., Chau, M. T., Sham, P. C., and Lam, K. S. (2008) Epidermal fatty-acid-binding protein: a new circulating biomarker associated with cardio-metabolic risk factors and carotid atherosclerosis. Eur. Heart J. 29, 2156-2163
29. Schug, T. T., Berry, D. C., Toshkov, I. A., Cheng, L., Nikitin, A. Y., and Noy, N. (2008) Overcoming retinoic acid-resistance of mammary carcinomas by diverting retinoic acid from PPARβ/ δ to RAR. Proc. Natl. Acad. Sci. U.S.A. 105, 7546-7551 (Pubitemid 351830055)
30. Morgan, E., Kannan-Thulasiraman, P., and Noy, N. (2010) Involvement of fatty acid binding protein 5 and PPARβ/δ in prostate cancer cell growth. PPAR Res. 2010 pii: 234629
31. Jeong, C. Y., Hah, Y. S., Cho, B. I., Lee, S. M., Joo, Y. T., Jung, E. J., Jeong, S. H., Lee, Y. J., Choi, S. K., Ha, W. S., Park, S. T., and Hong, S. C. (2012) Fatty acid-binding protein 5 promotes cell proliferation and invasion in human intrahepatic cholangiocarcinoma. Oncol. Rep. 28, 1283-1292
32. Kannan-Thulasiraman, P., Seachrist, D. D., Mahabeleshwar, G. H., Jain, M. K., and Noy, N. (2010) Fatty acid-binding protein 5 and PPARβ/δ are critical mediators of epidermal growth factor receptor-induced carcinoma cell growth. J. Biol. Chem. 285, 19106-19115
33. Levi, L., Lobo, G., Doud, M. K., von Lintig, J., Seachrist, D., Tochtrop, G. P., and Noy, N. (2013) Genetic ablation of the fatty acid-binding protein FABP5 suppresses HER2-induced mammary tumorigenesis. Cancer Res. 73, 4770-4780
34. Cologna, S. M., Jiang, X. S., Backlund, P. S., Cluzeau, C. V., Dail, M. K., Yanjanin, N. M., Siebel, S., Toth, C. L., Jun, H. S., Wassif, C. A., Yergey, A. L., and Porter, F. D. (2012) Quantitative proteomic analysis of Niemann-Pick disease, type C1 cerebellum identifies protein biomarkers and provides pathological insight. PLoS One 7, e47845
35. Barak, Y., Liao, D., He, W., Ong, E. S., Nelson, M. C., Olefsky, J. M., Boland, R., and Evans, R. M. (2002) Effects of peroxisome proliferator-activated receptor δ on placentation, adiposity, and colorectal cancer. Proc. Natl. Acad. Sci. U.S.A. 99, 303-308 (Pubitemid 34060358)
36. Akiyama, T. E., Lambert, G., Nicol, C. J., Matsusue, K., Peters, J. M., Brewer, H. B., Jr., and Gonzalez, F. J. (2004) Peroxisome proliferator-activated receptor β/δ regulates very low density lipoprotein production and catabolism in mice on a Western diet. J. Biol. Chem. 279, 20874-20881 (Pubitemid 38656484)
37. Lee, C. H., Olson, P., Hevener, A., Mehl, I., Chong, L. W., Olefsky, J. M., Gonzalez, F. J., Ham, J., Kang, H., Peters, J. M., and Evans, R. M. (2006) PPARδ regulates glucose metabolism and insulin sensitivity. Proc. Natl. Acad. Sci. U.S.A. 103, 3444-3449 (Pubitemid 43346488)
38. Nadra, K., Anghel, S. I., Joye, E., Tan, N. S., Basu-Modak, S., Trono, D., Wahli, W., and Desvergne, B. (2006) Differentiation of trophoblast giant cells and their metabolic functions are dependent on peroxisome proliferator-activated receptor β/δ. Mol. Cell. Biol. 26, 3266-3281
39. Tan, N. S., Michalik, L., Noy, N., Yasmin, R., Pacot, C., Heim, M., Flühmann, B., Desvergne, B., and Wahli, W. (2001) Critical roles of PPARβ/δ in keratinocyte response to inflammation. Genes Dev. 15, 3263-3277 (Pubitemid 34008192)
40. Di-Poï, N., Tan, N. S., Michalik, L., Wahli, W., and Desvergne, B. (2002) Antiapoptotic role of PPARδ in keratinocytes via transcriptional control of the Akt1 signaling pathway. Mol. Cell 10, 721-733 (Pubitemid 35335629)
41. Gillilan, R. E., Ayers, S. D., and Noy, N. (2007) Structural basis for activation of fatty acid-binding protein 4. J. Mol. Biol. 372, 1246-1260 (Pubitemid 47374720)
42. Bligh, E. G., and Dyer, W. J. (1959) A rapid method of total lipid extraction and purification. Can. J. Biochem. Physiol. 37, 911-917
43. Otwinowski, Z., and Minor, W. (1997) Processing of x-ray diffraction data collected in oscillation mode. Methods Enzymol. 276, 307-326 (Pubitemid 27085611)
44. McCoy, A. J., Grosse-Kunstleve, R. W., Adams, P. D., Winn, M. D., Storoni, L. C., and Read, R. J. (2007) Phaser crystallographic software. J. Appl. Crystallogr. 40, 658-674 (Pubitemid 47080256)
45. Emsley, P., and Cowtan, K. (2004) Coot: model-building tools for molecular graphics. Acta Crystallogr. D Biol. Crystallogr. 60, 2126-2132 (Pubitemid 41742764)
46. Adams, P. D., Afonine, P. V., Bunkóczi, G., Chen, V. B., Davis, I. W., Echols, N., Headd, J. J., Hung, L. W., Kapral, G. J., Grosse-Kunstleve, R. W., Mc-Coy, A. J., Moriarty, N. W., Oeffner, R., Read, R. J., Richardson, D. C., Richardson, J. S., Terwilliger, T. C., and Zwart, P. H. (2010) PHENIX: a comprehensive Python-based system for macromolecular structure solution. Acta Crystallogr. D Biol. Crystallogr. 66, 213-221
47. Dolinsky, T. J., Nielsen, J. E., McCammon, J. A., and Baker, N. A. (2004) PDB2PQR: an automated pipeline for the setup of Poisson-Boltzmann electrostatics calculations. Nucleic Acids Res. 32, W665-W667 (Pubitemid 38997419)
48. Baker, N. A., Sept, D., Joseph, S., Holst, M. J., and McCammon, J. A. (2001) Electrostatics of nanosystems: application to microtubules and the ribosome. Proc. Natl. Acad. Sci. U.S.A. 98, 10037-10041 (Pubitemid 32802969)
49. Dundas, J., Ouyang, Z., Tseng, J., Binkowski, A., Turpaz, Y., and Liang, J. (2006) CASTp: computed atlas of surface topography of proteins with structural and topographical mapping of functionally annotated residues. Nucleic Acids Res. 34, W116-W118 (Pubitemid 44529746)
50. Chen, V. B., Arendall, W. B., 3rd, Headd, J. J., Keedy, D. A., Immormino, R. M., Kapral, G. J., Murray, L. W., Richardson, J. S., and Richardson, D. C. (2010) Mol Probity: all-atom structure validation for macromolecular crystallography. Acta Crystallogr. D Biol. Crystallogr. 66, 12-21
51. Kane, C. D., and Bernlohr, D. A. (1996) A simple assay for intracellular lipid-binding proteins using displacement of 1-anilinonaphthalene 8-sulfonic acid. Anal. Biochem. 233, 197-204 (Pubitemid 26028229)
52. Chalmers, M. J., Busby, S. A., Pascal, B. D., He, Y., Hendrickson, C. L., Marshall, A. G., and Griffin, P. R. (2006) Probing protein ligand interactions by automated hydrogen/deuterium exchange mass spectrometry. Anal. Chem. 78, 1005-1014 (Pubitemid 43271829)
53. Pascal, B. D., Willis, S., Lauer, J. L., Landgraf, R. R., West, G. M., Marciano, D., Novick, S., Goswami, D., Chalmers, M. J., and Griffin, P. R. (2012)HDX workbench: software for the analysis of H/D exchangeMSdata. J. Am. Soc. Mass Spectrom. 23, 1512-1521
54. Hohoff, C., Börchers, T., Rüstow, B., Spener, F., and van Tilbeurgh, H. (1999) Expression, purification, and crystal structure determination of recombinant human epidermal-type fatty acid binding protein. Biochemistry 38, 12229-12239
55. Gutiérrez-González, L. H., Ludwig, C., Hohoff, C., Rademacher, M., Hanhoff, T., Rüterjans, H., Spener, F., and Lücke, C. (2002) Solution structure and backbone dynamics of human epidermal-type fatty acid-binding protein (E-FABP). Biochem. J. 364, 725-737 (Pubitemid 34680849)
56. Hanhoff, T., Lücke, C., and Spener, F. (2002) Insights into binding of fatty acids by fatty acid binding proteins. Mol. Cell. Biochem. 239, 45-54 (Pubitemid 35385794)
57. Xu, Z., Bernlohr, D. A., and Banaszak, L. J. (1993) The adipocyte lipidbinding protein at 1.6-Å resolution. Crystal structures of the apoprotein and with bound saturated and unsaturated fatty acids. J. Biol. Chem. 268, 7874-7884 (Pubitemid 23120364)
58. Richieri, G. V., Ogata, R. T., and Kleinfeld, A. M. (1994) Equilibrium constants for the binding of fatty acids with fatty acid-binding proteins from adipocyte, intestine, heart, and liver measured with the fluorescent probe ADIFAB. J. Biol. Chem. 269, 23918-23930
59. Richieri, G. V., Ogata, R. T., Zimmerman, A. W., Veerkamp, J. H., and Kleinfeld, A. M. (2000) Fatty acid binding proteins from different tissues show distinct patterns of fatty acid interactions. Biochemistry 39, 7197-7204 (Pubitemid 30413109)
60. Seibel, N. M., Eljouni, J., Nalaskowski, M. M., and Hampe, W. (2007) Nuclear localization of enhanced green fluorescent protein homomultimers. Anal. Biochem. 368, 95-99 (Pubitemid 47058434)
61. Sessler, R. J., and Noy, N. (2005) A ligand-activated nuclear localization signal in cellular retinoic acid binding protein-II. Mol. Cell 18, 343-353 (Pubitemid 41350539)
62. McLane, L. M., and Corbett, A. H. (2009) Nuclear localization signals and human disease. IUBMB Life 61, 697-706
63. Kutay, U., and Güttinger, S. (2005) Leucine-rich nuclear-export signals: born to be weak. Trends Cell Biol. 15, 121-124 (Pubitemid 40332533)
64. Sacchettini, J. C., Gordon, J. I., and Banaszak, L. J. (1989) Refined apoprotein structure of rat intestinal fatty acid binding protein produced in Escherichia coli. Proc. Natl. Acad. Sci. U.S.A. 86, 7736-7740 (Pubitemid 19265262)
65. Ockner, R. K., Manning, J. A., Poppenhausen, R. B., and Ho, W. K. (1972) A binding protein for fatty acids in cytosol of intestinal mucosa, liver, myocardium, and other tissues. Science 177, 56-58
66. Hertzel, A. V., Hellberg, K., Reynolds, J. M., Kruse, A. C., Juhlmann, B. E., Smith, A. J., Sanders, M. A., Ohlendorf, D. H., Suttles, J., and Bernlohr, D. A. (2009) Identification and characterization of a small molecule inhibitor of fatty acid binding proteins. J. Med. Chem. 52, 6024-6031
67. Hostetler, H. A., Balanarasimha, M., Huang, H., Kelzer, M. S., Kaliappan, A., Kier, A. B., and Schroeder, F. (2010) Glucose regulates fatty acid binding protein interaction with lipids and peroxisome proliferator-activated receptorα. J. Lipid Res. 51, 3103-3116
68. Velkov, T. (2013) Interactions between human liver fatty acid binding protein and peroxisome proliferator activated receptor selective drugs. PPAR Res. 2013, 938401
69. Budhu, A. S., and Noy, N. (2002) Direct channeling of retinoic acid between cellular retinoic acid-binding protein II and retinoic acid receptor sensitizes mammary carcinoma cells to retinoic acid-induced growth arrest. Mol. Cell. Biol. 22, 2632-2641 (Pubitemid 34262985)
70. Majumdar, A., Petrescu, A. D., Xiong, Y., and Noy, N. (2011) Nuclear translocation of cellular retinoic acid-binding protein II is regulated by retinoic acid-controlled SUMOylation. J. Biol. Chem. 286, 42749-42757
71. Sievers, F., Wilm, A., Dineen, D., Gibson, T. J., Karplus, K., Li, W., Lopez, R., McWilliam, H., Remmert, M., Söding, J., Thompson, J. D., and Higgins, D. G. (2011) Fast, scalable generation of high-quality protein multiple sequence alignments using Clustal Omega. Mol. Syst. Biol. 7, 539
72. Greenfield, S., Brostoff, S., Eylar, E. H., and Morell, P. (1973) Protein composition of myelin of the peripheral nervous system. J. Neurochem. 20, 1207-1216
73. Berry, D. C., O'Byrne, S. M., Vreeland, A. C., Blaner, W. S., and Noy, N. (2012) Cross talk between signaling and vitamin A transport by the retinol-binding protein receptor STRA6. Mol. Cell. Biol. 32, 3164-3175
74. Liu, R. Z., Li, X., and Godbout, R. (2008)Anovel fatty acid-binding protein (FABP) gene resulting from tandem gene duplication in mammals: transcription in rat retina and testis. Genomics 92, 436-445
75. Angelucci, F., Johnson, K. A., Baiocco, P., Miele, A. E., Brunori, M., Valle, C., Vigorosi, F., Troiani, A. R., Liberti, P., Cioli, D., Klinkert, M. Q., and Bellelli, A. (2004) Schistosoma mansoni fatty acid binding protein: specificity and functional control as revealed by crystallographic structure. Biochemistry 43, 13000-13011 (Pubitemid 39362769)