Abstract
The human recessive disorder abetalipoproteinemia is associated with a complete inability to assemble and secrete apo B-containing lipoproteins by both the liver and intestine. The gene responsible for this disease does not co-segregate with the apo a gene suggesting it is caused by the loss of some gene product. To gain an understanding of the apparently unique process necessary for apo a secretion, plasmids expressing apo a were transfected into Chinese hamster ovary fibroblasts. Expression of a truncated form (apo B15, consisting of 15% of the N-terminus of the full length protein), which is too short to assemble lipoproteins, resulted in the accumulation of apo a in both cells and culture medium. In contrast, cells transfected with a plasmid encoding apo B53 (which is sufficiently large to allow the assembly and secretion of lipoproteins when expressed in hepatoma cells) did not contain apo a nor did they secrete it despite the presence of apo a mRNA. Incubation with calpain inhibitor I (ALLN) led to the accumulation of apo B53 in cells, showing that it is synthesized, but completely degraded in the absence of the inhibitor. Despite the accumulation of apo B53 in ALLN-treated cells, none was secreted. The inability of Chinese hamster ovary cells to secrete apo B53 cannot be explained by insufficient lipid since stimulation of triglyceride synthesis did not induce secretion. Essentially all of the apo B53 which accumulated in the microsomes from ALLN-treated cells was bound to microsomal membranes and susceptible to degradation by exogenous trypsin, while the lumenal enzyme protein disulfide isomerase was fully protected. These data suggest that translocation is the step in the secretory pathway responsible for sorting apo a into either the secretory or degradation (i.e. default) pathways. Moreover, it appears that apo B requires a unique process, not expressed in Chinese hamster ovary cells, for its translocation. This process required for translocation may be lacking in abetalipoproteinemia. Based on the findings that essentially no toxicity is associated with either the abetalipoproteinemic phenotype or the phenotype created using fibroblast cells reported here, we propose that agents that would create the abetalipoproteinemic phenotype would be useful in treating hyperlipidemic conditions associated with increased plasma apo a levels.
*
Work supported by NIH grant HL 41624
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
Preview
Unable to display preview. Download preview PDF.
References
Alexander, C.A., Hamilton, R.L. and Havel, RJ. (1976) J. Cell Biol. 69:241–263
Young, S.G. (1990) Circulation 82:1574–1594.
Yao Z., Blackhart, B.D., Linton, M.F., Taylor, S.M., Young, S.G. and McCarthy, B.J. (1991) J. Biol. Chem. 266, 3300–3308.
Kane, J.P. (1983) Apolipoprotein B: structural and metabolic heterogeneity. Ann. Rev. Physiol. 45, 637–650.
Yang, C.-Y., Chen, S.-H., Gianturco, S.H., Bradley, W.A., Sparrow, J.T., Tanimura M., Li, W.-H., Sparrow, D.A., DeLoof H., Rosseneu M., Lee, F.-S., Gu, Z.-W., Gotto, A.M., Chan, L. (1986) Sequence, structure, receptor-binding domains and internal repeats of human apolipoprotein B-100. Nature 323, 738–742.
Yang, C.-Y., Gu, Z.-W., Weng, S.-a, Kim, T.W., Chen, S.-H., Pownall, H.J., Sharp, P.M., Liu, S.-W., Li, W.-H., Gotto, A.M., Chan, L. (1989) Structure of apolipoprotein B-100 of human low density lipoproteins. Arteriosclerosis 9, 96–108.
Chen, G.C., Hardman, D.A., Hamilton, R.L., Mendel, CM., Schilling, J.W., Zhu S., Lau K., Wong, J.S., Kane, J.P. (1989) Distribution of lipid-binding regions in human apolipoprotein B-100. Biochemistry 28, 2477–2484.
Cladaras, C, Hadzopoulou-Cladaras M., Nolte, R.T., Atkinson D., Zannis, V.I. (1986) The complete sequence and structural analysis of human apolipoprotein B-100: relationship between apoB-100 and apoB-48 forms. EMBO Journal 5, 3495–3507.
Blobel, G. (1980) Proc. Natl. Acad. Sci. USA 77:1496–1500.
Gething, M.-J. and Sambrook, J. (1982) Nature 200:598–603.
Boeke, J.D. and Model, P. (1982) Proc. Natl. Acad. Sci. USA 79:5200–5204.
Rose, J.K. and Bergmann, J.E. (1982) Cell 30:753–762.
Yost, C.S., Hedgpeth, J. and Lingappa, V.R. (1983) Cell 34:759–766.
Davis, R.A., Thrift, R.N., Wu, C.C. and Howell, K.E. (1990) J. Biol. Chem. 265, 10005–10011.
Leighton, J.K., Joyner J., Zamarripa J., Deines, M. and Davis, R.A. (1990) J. Lipid Res. 31:1663–1668.
Davidson, N.O., Powell, L.M., Wallis, S.C. and Scott, J. (1988) J. Biol. Chem. 203:13482–13485.
Pullinger, C.R., North, J.D., Teng, B.-B., Rifìcini, V.A., Ronhild de Brito, A.E. and Scott, J. (1989) J. Lipid Res. 30:1065–1077.
Borchardt, R.A. and Davis, R.A. (1987) J. Biol. Chem. 262, 16394–21642.
Davis, R.A., Prewett, A.B., Chan, D.C.F., Thompson, J.J., Borchardt, R.A. and Gallaher, W.R. (1989) J. Lipid Res. 30, 1185–1196.
Sato R., Imanaka T., Takatsuki, A. and Takano, T. (1990) J. Biol. Chem. 265, 11880–11884.
Talmud, P.J., Lloyd J.K., Muller, D.R., Collins, D.R., Scott, J. and Humphries, S. (1988) J. Clin. Invest. 82, 1803–1806.
Lackner, K.J., Monge, J.C., Gregg, R.E., Hoeg, J.M., Triche, T.J., Law, S.W. and Brewer, H.B., Jr. (1986) J. Clin. Invest. 78, 1707–1712.
Dullaart, R.P.F., Speelberg B., Schuurman, H.J., Milne, R.W., Havekes, L. Marcel, Y.L., Genze H.J., Hulshox, M.M. and Erkelens, D.W. (1986) J. Clin. Invest 78, 1397–1404.
Bouma, M.E., Beucler I., Pessah M., Heinzmann, C, Lusis, A.J., Nairn, H.Y., Ducastelle T., Leluyer B., Schmitz J., Infante, R. and Aggerbeck, L.P. (1990) J. Lipid Res. 31, 1–15.
Kayden, H.J. (1972) Ann. Rev. Med. 23:285–296.
Herbert, P.N., Assman G., Gotto, A.M. and Fredrickson, D.S. (1983) in Metabolic Basis of Inherited Disease, 5th Edition, eds. Stanbury, J.B., Wyngaarden, J.B., Fredrickson, D.S., Goldstein, J.L., and Brown, M.S., (McGraw-Hill, New York, NY), pp 589–691.
Malloy, M.J. and Kane, J.P. (1982) Med. Clin. N. Am. 66:469–488.
Thrift, R.N., Drisko J., Dueland S., Trawick, J.D. and Davis, R.A. (1992) (In Press).
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 1993 Springer Science+Business Media Dordrecht
About this chapter
Cite this chapter
Davis, R.A. (1993). Lipoprotein Assembly: A Potential Target for Drugs Affecting Lipid Metabolism. In: Catapano, A.L., Gotto, A.M., Smith, L.C., Paoletti, R. (eds) Drugs Affecting Lipid Metabolism. Medical Science Symposia Series, vol 2. Springer, Dordrecht. https://doi.org/10.1007/978-94-011-1703-6_11
Download citation
DOI: https://doi.org/10.1007/978-94-011-1703-6_11
Publisher Name: Springer, Dordrecht
Print ISBN: 978-94-010-4746-3
Online ISBN: 978-94-011-1703-6
eBook Packages: Springer Book Archive