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. 2001 Mar;157(3):1117–1140. doi: 10.1093/genetics/157.3.1117

Overlapping functions of the yeast oxysterol-binding protein homologues.

C T Beh 1, L Cool 1, J Phillips 1, J Rine 1
PMCID: PMC1461579  PMID: 11238399

Abstract

The Saccharomyces cerevisiae genome encodes seven homologues of the mammalian oxysterol-binding protein (OSBP), a protein implicated in lipid trafficking and sterol homeostasis. To determine the functions of the yeast OSBP gene family (OSH1-OSH7), we used a combination of genetics, genomics, and sterol lipid analysis to characterize OSH deletion mutants. All 127 combinations and permutations of OSH deletion alleles were constructed. Individual OSH genes were not essential for yeast viability, but the elimination of the entire gene family was lethal. Thus, the family members shared an essential function. In addition, the in vivo depletion of all Osh proteins disrupted sterol homeostasis. Like mutants that affect ergosterol production, the viable combinations of OSH deletion alleles exhibited specific sterol-related defects. Although none of the single OSH deletion mutants was defective for growth, gene expression profiles revealed that each mutant had a characteristic molecular phenotype. Therefore, each gene performed distinct nonessential functions and contributed to a common essential function. Our findings indicated that OSH genes performed a multitude of nonessential roles defined by specific subsets of the genes and that most shared at least one essential role potentially linked to changes in sterol lipid levels.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Adams M. D., Celniker S. E., Holt R. A., Evans C. A., Gocayne J. D., Amanatides P. G., Scherer S. E., Li P. W., Hoskins R. A., Galle R. F. The genome sequence of Drosophila melanogaster. Science. 2000 Mar 24;287(5461):2185–2195. doi: 10.1126/science.287.5461.2185. [DOI] [PubMed] [Google Scholar]
  2. Alberts A. W., Chen J., Kuron G., Hunt V., Huff J., Hoffman C., Rothrock J., Lopez M., Joshua H., Harris E. Mevinolin: a highly potent competitive inhibitor of hydroxymethylglutaryl-coenzyme A reductase and a cholesterol-lowering agent. Proc Natl Acad Sci U S A. 1980 Jul;77(7):3957–3961. doi: 10.1073/pnas.77.7.3957. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Alphey L., Jimenez J., Glover D. A Drosophila homologue of oxysterol binding protein (OSBP)--implications for the role of OSBP. Biochim Biophys Acta. 1998 Jan 21;1395(2):159–164. doi: 10.1016/s0167-4781(97)00159-0. [DOI] [PubMed] [Google Scholar]
  4. Altschul S. F., Gish W., Miller W., Myers E. W., Lipman D. J. Basic local alignment search tool. J Mol Biol. 1990 Oct 5;215(3):403–410. doi: 10.1016/S0022-2836(05)80360-2. [DOI] [PubMed] [Google Scholar]
  5. Bankaitis V. A., Malehorn D. E., Emr S. D., Greene R. The Saccharomyces cerevisiae SEC14 gene encodes a cytosolic factor that is required for transport of secretory proteins from the yeast Golgi complex. J Cell Biol. 1989 Apr;108(4):1271–1281. doi: 10.1083/jcb.108.4.1271. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Bard M., Woods R. A., Bartón D. H., Corrie J. E., Widdowson D. A. Sterol mutants of Saccharomyces cerevisiae: chromatographic analyses. Lipids. 1977 Aug;12(8):645–654. doi: 10.1007/BF02533759. [DOI] [PubMed] [Google Scholar]
  7. Brown M. S., Goldstein J. L. A proteolytic pathway that controls the cholesterol content of membranes, cells, and blood. Proc Natl Acad Sci U S A. 1999 Sep 28;96(20):11041–11048. doi: 10.1073/pnas.96.20.11041. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. Brown M. S., Goldstein J. L. The SREBP pathway: regulation of cholesterol metabolism by proteolysis of a membrane-bound transcription factor. Cell. 1997 May 2;89(3):331–340. doi: 10.1016/s0092-8674(00)80213-5. [DOI] [PubMed] [Google Scholar]
  9. C. elegans Sequencing Consortium Genome sequence of the nematode C. elegans: a platform for investigating biology. Science. 1998 Dec 11;282(5396):2012–2018. doi: 10.1126/science.282.5396.2012. [DOI] [PubMed] [Google Scholar]
  10. Chou P. Y., Fasman G. D. Prediction of the secondary structure of proteins from their amino acid sequence. Adv Enzymol Relat Areas Mol Biol. 1978;47:45–148. doi: 10.1002/9780470122921.ch2. [DOI] [PubMed] [Google Scholar]
  11. Daum G., Tuller G., Nemec T., Hrastnik C., Balliano G., Cattel L., Milla P., Rocco F., Conzelmann A., Vionnet C. Systematic analysis of yeast strains with possible defects in lipid metabolism. Yeast. 1999 May;15(7):601–614. doi: 10.1002/(SICI)1097-0061(199905)15:7<601::AID-YEA390>3.0.CO;2-N. [DOI] [PubMed] [Google Scholar]
  12. Dawson P. A., Ridgway N. D., Slaughter C. A., Brown M. S., Goldstein J. L. cDNA cloning and expression of oxysterol-binding protein, an oligomer with a potential leucine zipper. J Biol Chem. 1989 Oct 5;264(28):16798–16803. [PubMed] [Google Scholar]
  13. Dawson P. A., Van der Westhuyzen D. R., Goldstein J. L., Brown M. S. Purification of oxysterol binding protein from hamster liver cytosol. J Biol Chem. 1989 May 25;264(15):9046–9052. [PubMed] [Google Scholar]
  14. Dimster-Denk D., Thorsness M. K., Rine J. Feedback regulation of 3-hydroxy-3-methylglutaryl coenzyme A reductase in Saccharomyces cerevisiae. Mol Biol Cell. 1994 Jun;5(6):655–665. doi: 10.1091/mbc.5.6.655. [DOI] [PMC free article] [PubMed] [Google Scholar]
  15. Dutcher S. K. Internuclear transfer of genetic information in kar1-1/KAR1 heterokaryons in Saccharomyces cerevisiae. Mol Cell Biol. 1981 Mar;1(3):245–253. doi: 10.1128/mcb.1.3.245. [DOI] [PMC free article] [PubMed] [Google Scholar]
  16. Fang M., Kearns B. G., Gedvilaite A., Kagiwada S., Kearns M., Fung M. K., Bankaitis V. A. Kes1p shares homology with human oxysterol binding protein and participates in a novel regulatory pathway for yeast Golgi-derived transport vesicle biogenesis. EMBO J. 1996 Dec 2;15(23):6447–6459. [PMC free article] [PubMed] [Google Scholar]
  17. Fournier M. V., Guimarães da Costa F., Paschoal M. E., Ronco L. V., Carvalho M. G., Pardee A. B., Giumaraes F. C. Identification of a gene encoding a human oxysterol-binding protein-homologue: a potential general molecular marker for blood dissemination of solid tumors. Cancer Res. 1999 Aug 1;59(15):3748–3753. [PubMed] [Google Scholar]
  18. Gaber R. F., Copple D. M., Kennedy B. K., Vidal M., Bard M. The yeast gene ERG6 is required for normal membrane function but is not essential for biosynthesis of the cell-cycle-sparking sterol. Mol Cell Biol. 1989 Aug;9(8):3447–3456. doi: 10.1128/mcb.9.8.3447. [DOI] [PMC free article] [PubMed] [Google Scholar]
  19. Goffeau A., Barrell B. G., Bussey H., Davis R. W., Dujon B., Feldmann H., Galibert F., Hoheisel J. D., Jacq C., Johnston M. Life with 6000 genes. Science. 1996 Oct 25;274(5287):546, 563-7. doi: 10.1126/science.274.5287.546. [DOI] [PubMed] [Google Scholar]
  20. Goldstein J. L., Brown M. S. Regulation of the mevalonate pathway. Nature. 1990 Feb 1;343(6257):425–430. doi: 10.1038/343425a0. [DOI] [PubMed] [Google Scholar]
  21. Hemmings B. A. PH domains--a universal membrane adapter. Science. 1997 Mar 28;275(5308):1899–1899. doi: 10.1126/science.275.5308.1899. [DOI] [PubMed] [Google Scholar]
  22. Hildebrandt E. R., Hoyt M. A. Mitotic motors in Saccharomyces cerevisiae. Biochim Biophys Acta. 2000 Mar 17;1496(1):99–116. doi: 10.1016/s0167-4889(00)00012-4. [DOI] [PubMed] [Google Scholar]
  23. Hull C. M., Johnson A. D. Identification of a mating type-like locus in the asexual pathogenic yeast Candida albicans. Science. 1999 Aug 20;285(5431):1271–1275. doi: 10.1126/science.285.5431.1271. [DOI] [PubMed] [Google Scholar]
  24. Jiang B., Brown J. L., Sheraton J., Fortin N., Bussey H. A new family of yeast genes implicated in ergosterol synthesis is related to the human oxysterol binding protein. Yeast. 1994 Mar;10(3):341–353. doi: 10.1002/yea.320100307. [DOI] [PubMed] [Google Scholar]
  25. Kandutsch A. A., Chen H. W., Heiniger H. J. Biological activity of some oxygenated sterols. Science. 1978 Aug 11;201(4355):498–501. doi: 10.1126/science.663671. [DOI] [PubMed] [Google Scholar]
  26. Kyte J., Doolittle R. F. A simple method for displaying the hydropathic character of a protein. J Mol Biol. 1982 May 5;157(1):105–132. doi: 10.1016/0022-2836(82)90515-0. [DOI] [PubMed] [Google Scholar]
  27. Lagace T. A., Byers D. M., Cook H. W., Ridgway N. D. Altered regulation of cholesterol and cholesteryl ester synthesis in Chinese-hamster ovary cells overexpressing the oxysterol-binding protein is dependent on the pleckstrin homology domain. Biochem J. 1997 Aug 15;326(Pt 1):205–213. doi: 10.1042/bj3260205. [DOI] [PMC free article] [PubMed] [Google Scholar]
  28. Lange Y., Steck T. L. Four cholesterol-sensing proteins. Curr Opin Struct Biol. 1998 Aug;8(4):435–439. doi: 10.1016/s0959-440x(98)80119-x. [DOI] [PubMed] [Google Scholar]
  29. Levanon D., Hsieh C. L., Francke U., Dawson P. A., Ridgway N. D., Brown M. S., Goldstein J. L. cDNA cloning of human oxysterol-binding protein and localization of the gene to human chromosome 11 and mouse chromosome 19. Genomics. 1990 May;7(1):65–74. doi: 10.1016/0888-7543(90)90519-z. [DOI] [PubMed] [Google Scholar]
  30. Levine T. P., Munro S. The pleckstrin homology domain of oxysterol-binding protein recognises a determinant specific to Golgi membranes. Curr Biol. 1998 Jun 18;8(13):729–739. doi: 10.1016/s0960-9822(98)70296-9. [DOI] [PubMed] [Google Scholar]
  31. Li X., Routt S. M., Xie Z., Cui X., Fang M., Kearns M. A., Bard M., Kirsch D. R., Bankaitis V. A. Identification of a novel family of nonclassic yeast phosphatidylinositol transfer proteins whose function modulates phospholipase D activity and Sec14p-independent cell growth. Mol Biol Cell. 2000 Jun;11(6):1989–2005. doi: 10.1091/mbc.11.6.1989. [DOI] [PMC free article] [PubMed] [Google Scholar]
  32. Li X., Xie Z., Bankaitis V. A. Phosphatidylinositol/phosphatidylcholine transfer proteins in yeast. Biochim Biophys Acta. 2000 Jun 26;1486(1):55–71. doi: 10.1016/s1388-1981(00)00048-2. [DOI] [PubMed] [Google Scholar]
  33. Lupas A. Prediction and analysis of coiled-coil structures. Methods Enzymol. 1996;266:513–525. doi: 10.1016/s0076-6879(96)66032-7. [DOI] [PubMed] [Google Scholar]
  34. Nes W. D., Xu S. H., Haddon W. F. Evidence for similarities and differences in the biosynthesis of fungal sterols. Steroids. 1989 Mar-May;53(3-5):533–558. doi: 10.1016/0039-128x(89)90030-5. [DOI] [PubMed] [Google Scholar]
  35. Ridgway N. D., Dawson P. A., Ho Y. K., Brown M. S., Goldstein J. L. Translocation of oxysterol binding protein to Golgi apparatus triggered by ligand binding. J Cell Biol. 1992 Jan;116(2):307–319. doi: 10.1083/jcb.116.2.307. [DOI] [PMC free article] [PubMed] [Google Scholar]
  36. Ridgway N. D. Interactions between metabolism and intracellular distribution of cholesterol and sphingomyelin. Biochim Biophys Acta. 2000 Apr 12;1484(2-3):129–141. doi: 10.1016/s1388-1981(00)00006-8. [DOI] [PubMed] [Google Scholar]
  37. Robinson J. S., Klionsky D. J., Banta L. M., Emr S. D. Protein sorting in Saccharomyces cerevisiae: isolation of mutants defective in the delivery and processing of multiple vacuolar hydrolases. Mol Cell Biol. 1988 Nov;8(11):4936–4948. doi: 10.1128/mcb.8.11.4936. [DOI] [PMC free article] [PubMed] [Google Scholar]
  38. Russell D. W. Nuclear orphan receptors control cholesterol catabolism. Cell. 1999 May 28;97(5):539–542. doi: 10.1016/s0092-8674(00)80763-1. [DOI] [PubMed] [Google Scholar]
  39. Schmalix W. A., Bandlow W. SWH1 from yeast encodes a candidate nuclear factor containing ankyrin repeats and showing homology to mammalian oxysterol-binding protein. Biochim Biophys Acta. 1994 Sep 13;1219(1):205–210. doi: 10.1016/0167-4781(94)90273-9. [DOI] [PubMed] [Google Scholar]
  40. Schroepfer G. J., Jr Oxysterols: modulators of cholesterol metabolism and other processes. Physiol Rev. 2000 Jan;80(1):361–554. doi: 10.1152/physrev.2000.80.1.361. [DOI] [PubMed] [Google Scholar]
  41. Sikorski R. S., Hieter P. A system of shuttle vectors and yeast host strains designed for efficient manipulation of DNA in Saccharomyces cerevisiae. Genetics. 1989 May;122(1):19–27. doi: 10.1093/genetics/122.1.19. [DOI] [PMC free article] [PubMed] [Google Scholar]
  42. Storey M. K., Byers D. M., Cook H. W., Ridgway N. D. Cholesterol regulates oxysterol binding protein (OSBP) phosphorylation and Golgi localization in Chinese hamster ovary cells: correlation with stimulation of sphingomyelin synthesis by 25-hydroxycholesterol. Biochem J. 1998 Nov 15;336(Pt 1):247–256. doi: 10.1042/bj3360247. [DOI] [PMC free article] [PubMed] [Google Scholar]
  43. Taylor F. R., Saucier S. E., Shown E. P., Parish E. J., Kandutsch A. A. Correlation between oxysterol binding to a cytosolic binding protein and potency in the repression of hydroxymethylglutaryl coenzyme A reductase. J Biol Chem. 1984 Oct 25;259(20):12382–12387. [PubMed] [Google Scholar]
  44. Vallen E. A., Hiller M. A., Scherson T. Y., Rose M. D. Separate domains of KAR1 mediate distinct functions in mitosis and nuclear fusion. J Cell Biol. 1992 Jun;117(6):1277–1287. doi: 10.1083/jcb.117.6.1277. [DOI] [PMC free article] [PubMed] [Google Scholar]
  45. Wach A., Brachat A., Pöhlmann R., Philippsen P. New heterologous modules for classical or PCR-based gene disruptions in Saccharomyces cerevisiae. Yeast. 1994 Dec;10(13):1793–1808. doi: 10.1002/yea.320101310. [DOI] [PubMed] [Google Scholar]
  46. Walker-Caprioglio H. M., MacKenzie J. M., Parks L. W. Antibodies to nystatin demonstrate polyene sterol specificity and allow immunolabeling of sterols in Saccharomyces cerevisiae. Antimicrob Agents Chemother. 1989 Dec;33(12):2092–2095. doi: 10.1128/aac.33.12.2092. [DOI] [PMC free article] [PubMed] [Google Scholar]
  47. Woods R. A. Nystatin-resistant mutants of yeast: alterations in sterol content. J Bacteriol. 1971 Oct;108(1):69–73. doi: 10.1128/jb.108.1.69-73.1971. [DOI] [PMC free article] [PubMed] [Google Scholar]
  48. Zinser E., Sperka-Gottlieb C. D., Fasch E. V., Kohlwein S. D., Paltauf F., Daum G. Phospholipid synthesis and lipid composition of subcellular membranes in the unicellular eukaryote Saccharomyces cerevisiae. J Bacteriol. 1991 Mar;173(6):2026–2034. doi: 10.1128/jb.173.6.2026-2034.1991. [DOI] [PMC free article] [PubMed] [Google Scholar]

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