Skip to main content
The Journal of Cell Biology logoLink to The Journal of Cell Biology
. 1995 Jul 2;130(2):299–312. doi: 10.1083/jcb.130.2.299

Sec6, Sec8, and Sec15 are components of a multisubunit complex which localizes to small bud tips in Saccharomyces cerevisiae

PMCID: PMC2199927  PMID: 7615633

Abstract

In the yeast Saccharomyces cerevisiae, the products of at least 14 genes are involved specifically in vesicular transport from the Golgi apparatus to the plasma membrane. Two of these genes, SEC8 and SEC15, encode components of a 1-2-million D multi-subunit complex that is found in the cytoplasm and associated with the plasma membrane. In this study, oligonucleotide-directed mutagenesis is used to alter the COOH- terminal portion of Sec8 with a 6-histidine tag, a 9E10 c-myc epitope, or both, to allow the isolation of the Sec8/15 complex from yeast lysates either by immobilized metal affinity chromatography or by immunoprecipitation. Sec6 cofractionates with Sec8/15 by immobilized metal affinity chromatography, gel filtration chromatography, and by sucrose velocity centrifugation. Sec6 and Sec15 coimmunoprecipitate from lysates with c-myc-tagged Sec8. These data indicate that the Sec8/15 complex contains Sec6 as a stable component. Additional proteins associated with Sec6/8/15 were identified by immunoprecipitations from radiolabeled lysates. The entire Sec6/8/15 complex contains at least eight polypeptides which range in molecular mass from 70 to 144 kD. Yeast strains containing temperature sensitive mutations in the SEC genes were also transformed with the SEC8-c-myc-6- histidine construct and analyzed by immunoprecipitation. The composition of the Sec6/8/15 complex is disrupted specifically in the sec3-2, sec5-24, and sec10-2 strain backgrounds. The c-myc-Sec8 protein is localized by immunofluorescence to small bud tips indicating that the Sec6/8/15 complex may function at sites of exocytosis.

Full Text

The Full Text of this article is available as a PDF (2.5 MB).

Selected References

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

  1. Aalto M. K., Ronne H., Keränen S. Yeast syntaxins Sso1p and Sso2p belong to a family of related membrane proteins that function in vesicular transport. EMBO J. 1993 Nov;12(11):4095–4104. doi: 10.1002/j.1460-2075.1993.tb06093.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Baumert M., Maycox P. R., Navone F., De Camilli P., Jahn R. Synaptobrevin: an integral membrane protein of 18,000 daltons present in small synaptic vesicles of rat brain. EMBO J. 1989 Feb;8(2):379–384. doi: 10.1002/j.1460-2075.1989.tb03388.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Bennett M. K., Calakos N., Scheller R. H. Syntaxin: a synaptic protein implicated in docking of synaptic vesicles at presynaptic active zones. Science. 1992 Jul 10;257(5067):255–259. doi: 10.1126/science.1321498. [DOI] [PubMed] [Google Scholar]
  4. Bennett M. K., Scheller R. H. The molecular machinery for secretion is conserved from yeast to neurons. Proc Natl Acad Sci U S A. 1993 Apr 1;90(7):2559–2563. doi: 10.1073/pnas.90.7.2559. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Bourne H. R. Do GTPases direct membrane traffic in secretion? Cell. 1988 Jun 3;53(5):669–671. doi: 10.1016/0092-8674(88)90081-5. [DOI] [PubMed] [Google Scholar]
  6. Bowser R., Müller H., Govindan B., Novick P. Sec8p and Sec15p are components of a plasma membrane-associated 19.5S particle that may function downstream of Sec4p to control exocytosis. J Cell Biol. 1992 Sep;118(5):1041–1056. doi: 10.1083/jcb.118.5.1041. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. Bowser R., Novick P. Sec15 protein, an essential component of the exocytotic apparatus, is associated with the plasma membrane and with a soluble 19.5S particle. J Cell Biol. 1991 Mar;112(6):1117–1131. doi: 10.1083/jcb.112.6.1117. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. Bradford M. M. A rapid and sensitive method for the quantitation of microgram quantities of protein utilizing the principle of protein-dye binding. Anal Biochem. 1976 May 7;72:248–254. doi: 10.1006/abio.1976.9999. [DOI] [PubMed] [Google Scholar]
  9. Brennwald P., Kearns B., Champion K., Keränen S., Bankaitis V., Novick P. Sec9 is a SNAP-25-like component of a yeast SNARE complex that may be the effector of Sec4 function in exocytosis. Cell. 1994 Oct 21;79(2):245–258. doi: 10.1016/0092-8674(94)90194-5. [DOI] [PubMed] [Google Scholar]
  10. Brennwald P., Novick P. Interactions of three domains distinguishing the Ras-related GTP-binding proteins Ypt1 and Sec4. Nature. 1993 Apr 8;362(6420):560–563. doi: 10.1038/362560a0. [DOI] [PubMed] [Google Scholar]
  11. Brockerhoff S. E., Stevens R. C., Davis T. N. The unconventional myosin, Myo2p, is a calmodulin target at sites of cell growth in Saccharomyces cerevisiae. J Cell Biol. 1994 Feb;124(3):315–323. doi: 10.1083/jcb.124.3.315. [DOI] [PMC free article] [PubMed] [Google Scholar]
  12. Calakos N., Bennett M. K., Peterson K. E., Scheller R. H. Protein-protein interactions contributing to the specificity of intracellular vesicular trafficking. Science. 1994 Feb 25;263(5150):1146–1149. doi: 10.1126/science.8108733. [DOI] [PubMed] [Google Scholar]
  13. Carlson M., Botstein D. Two differentially regulated mRNAs with different 5' ends encode secreted with intracellular forms of yeast invertase. Cell. 1982 Jan;28(1):145–154. doi: 10.1016/0092-8674(82)90384-1. [DOI] [PubMed] [Google Scholar]
  14. Evan G. I., Lewis G. K., Ramsay G., Bishop J. M. Isolation of monoclonal antibodies specific for human c-myc proto-oncogene product. Mol Cell Biol. 1985 Dec;5(12):3610–3616. doi: 10.1128/mcb.5.12.3610. [DOI] [PMC free article] [PubMed] [Google Scholar]
  15. Ferro-Novick S., Jahn R. Vesicle fusion from yeast to man. Nature. 1994 Jul 21;370(6486):191–193. doi: 10.1038/370191a0. [DOI] [PubMed] [Google Scholar]
  16. Garrett M. D., Kabcenell A. K., Zahner J. E., Kaibuchi K., Sasaki T., Takai Y., Cheney C. M., Novick P. J. Interaction of Sec4 with GDI proteins from bovine brain, Drosophila melanogaster and Saccharomyces cerevisiae. Conservation of GDI membrane dissociation activity. FEBS Lett. 1993 Oct 4;331(3):233–238. doi: 10.1016/0014-5793(93)80343-s. [DOI] [PubMed] [Google Scholar]
  17. Garrett M. D., Zahner J. E., Cheney C. M., Novick P. J. GDI1 encodes a GDP dissociation inhibitor that plays an essential role in the yeast secretory pathway. EMBO J. 1994 Apr 1;13(7):1718–1728. doi: 10.1002/j.1460-2075.1994.tb06436.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  18. Gerst J. E., Rodgers L., Riggs M., Wigler M. SNC1, a yeast homolog of the synaptic vesicle-associated membrane protein/synaptobrevin gene family: genetic interactions with the RAS and CAP genes. Proc Natl Acad Sci U S A. 1992 May 15;89(10):4338–4342. doi: 10.1073/pnas.89.10.4338. [DOI] [PMC free article] [PubMed] [Google Scholar]
  19. Goud B., Salminen A., Walworth N. C., Novick P. J. A GTP-binding protein required for secretion rapidly associates with secretory vesicles and the plasma membrane in yeast. Cell. 1988 Jun 3;53(5):753–768. doi: 10.1016/0092-8674(88)90093-1. [DOI] [PubMed] [Google Scholar]
  20. Griff I. C., Schekman R., Rothman J. E., Kaiser C. A. The yeast SEC17 gene product is functionally equivalent to mammalian alpha-SNAP protein. J Biol Chem. 1992 Jun 15;267(17):12106–12115. [PubMed] [Google Scholar]
  21. Ito H., Fukuda Y., Murata K., Kimura A. Transformation of intact yeast cells treated with alkali cations. J Bacteriol. 1983 Jan;153(1):163–168. doi: 10.1128/jb.153.1.163-168.1983. [DOI] [PMC free article] [PubMed] [Google Scholar]
  22. Kunkel T. A., Roberts J. D., Zakour R. A. Rapid and efficient site-specific mutagenesis without phenotypic selection. Methods Enzymol. 1987;154:367–382. doi: 10.1016/0076-6879(87)54085-x. [DOI] [PubMed] [Google Scholar]
  23. Laemmli U. K. Cleavage of structural proteins during the assembly of the head of bacteriophage T4. Nature. 1970 Aug 15;227(5259):680–685. doi: 10.1038/227680a0. [DOI] [PubMed] [Google Scholar]
  24. Lapetina E. G., Reep B. R. Specific binding of [alpha-32P]GTP to cytosolic and membrane-bound proteins of human platelets correlates with the activation of phospholipase C. Proc Natl Acad Sci U S A. 1987 Apr;84(8):2261–2265. doi: 10.1073/pnas.84.8.2261. [DOI] [PMC free article] [PubMed] [Google Scholar]
  25. Lian J. P., Stone S., Jiang Y., Lyons P., Ferro-Novick S. Ypt1p implicated in v-SNARE activation. Nature. 1994 Dec 15;372(6507):698–701. doi: 10.1038/372698a0. [DOI] [PubMed] [Google Scholar]
  26. Lillie S. H., Brown S. S. Immunofluorescence localization of the unconventional myosin, Myo2p, and the putative kinesin-related protein, Smy1p, to the same regions of polarized growth in Saccharomyces cerevisiae. J Cell Biol. 1994 May;125(4):825–842. doi: 10.1083/jcb.125.4.825. [DOI] [PMC free article] [PubMed] [Google Scholar]
  27. Nair J., Müller H., Peterson M., Novick P. Sec2 protein contains a coiled-coil domain essential for vesicular transport and a dispensable carboxy terminal domain. J Cell Biol. 1990 Jun;110(6):1897–1909. doi: 10.1083/jcb.110.6.1897. [DOI] [PMC free article] [PubMed] [Google Scholar]
  28. Novick P., Brennwald P. Friends and family: the role of the Rab GTPases in vesicular traffic. Cell. 1993 Nov 19;75(4):597–601. doi: 10.1016/0092-8674(93)90478-9. [DOI] [PubMed] [Google Scholar]
  29. Novick P., Ferro S., Schekman R. Order of events in the yeast secretory pathway. Cell. 1981 Aug;25(2):461–469. doi: 10.1016/0092-8674(81)90064-7. [DOI] [PubMed] [Google Scholar]
  30. Oyler G. A., Higgins G. A., Hart R. A., Battenberg E., Billingsley M., Bloom F. E., Wilson M. C. The identification of a novel synaptosomal-associated protein, SNAP-25, differentially expressed by neuronal subpopulations. J Cell Biol. 1989 Dec;109(6 Pt 1):3039–3052. doi: 10.1083/jcb.109.6.3039. [DOI] [PMC free article] [PubMed] [Google Scholar]
  31. Potenza M., Bowser R., Müller H., Novick P. SEC6 encodes an 85 kDa soluble protein required for exocytosis in yeast. Yeast. 1992 Jul;8(7):549–558. doi: 10.1002/yea.320080706. [DOI] [PubMed] [Google Scholar]
  32. Protopopov V., Govindan B., Novick P., Gerst J. E. Homologs of the synaptobrevin/VAMP family of synaptic vesicle proteins function on the late secretory pathway in S. cerevisiae. Cell. 1993 Sep 10;74(5):855–861. doi: 10.1016/0092-8674(93)90465-3. [DOI] [PubMed] [Google Scholar]
  33. Redding K., Holcomb C., Fuller R. S. Immunolocalization of Kex2 protease identifies a putative late Golgi compartment in the yeast Saccharomyces cerevisiae. J Cell Biol. 1991 May;113(3):527–538. doi: 10.1083/jcb.113.3.527. [DOI] [PMC free article] [PubMed] [Google Scholar]
  34. Rine J. Gene overexpression in studies of Saccharomyces cerevisiae. Methods Enzymol. 1991;194:239–251. doi: 10.1016/0076-6879(91)94019-9. [DOI] [PubMed] [Google Scholar]
  35. Roberts C. J., Raymond C. K., Yamashiro C. T., Stevens T. H. Methods for studying the yeast vacuole. Methods Enzymol. 1991;194:644–661. doi: 10.1016/0076-6879(91)94047-g. [DOI] [PubMed] [Google Scholar]
  36. Rothman J. E., Warren G. Implications of the SNARE hypothesis for intracellular membrane topology and dynamics. Curr Biol. 1994 Mar 1;4(3):220–233. doi: 10.1016/s0960-9822(00)00051-8. [DOI] [PubMed] [Google Scholar]
  37. Salminen A., Novick P. J. A ras-like protein is required for a post-Golgi event in yeast secretion. Cell. 1987 May 22;49(4):527–538. doi: 10.1016/0092-8674(87)90455-7. [DOI] [PubMed] [Google Scholar]
  38. Salminen A., Novick P. J. The Sec15 protein responds to the function of the GTP binding protein, Sec4, to control vesicular traffic in yeast. J Cell Biol. 1989 Sep;109(3):1023–1036. doi: 10.1083/jcb.109.3.1023. [DOI] [PMC free article] [PubMed] [Google Scholar]
  39. Sanger F., Nicklen S., Coulson A. R. DNA sequencing with chain-terminating inhibitors. Proc Natl Acad Sci U S A. 1977 Dec;74(12):5463–5467. doi: 10.1073/pnas.74.12.5463. [DOI] [PMC free article] [PubMed] [Google Scholar]
  40. 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]
  41. Smith D. B., Johnson K. S. Single-step purification of polypeptides expressed in Escherichia coli as fusions with glutathione S-transferase. Gene. 1988 Jul 15;67(1):31–40. doi: 10.1016/0378-1119(88)90005-4. [DOI] [PubMed] [Google Scholar]
  42. Snyder M., Gehrung S., Page B. D. Studies concerning the temporal and genetic control of cell polarity in Saccharomyces cerevisiae. J Cell Biol. 1991 Aug;114(3):515–532. doi: 10.1083/jcb.114.3.515. [DOI] [PMC free article] [PubMed] [Google Scholar]
  43. Söllner T., Whiteheart S. W., Brunner M., Erdjument-Bromage H., Geromanos S., Tempst P., Rothman J. E. SNAP receptors implicated in vesicle targeting and fusion. Nature. 1993 Mar 25;362(6418):318–324. doi: 10.1038/362318a0. [DOI] [PubMed] [Google Scholar]
  44. Søgaard M., Tani K., Ye R. R., Geromanos S., Tempst P., Kirchhausen T., Rothman J. E., Söllner T. A rab protein is required for the assembly of SNARE complexes in the docking of transport vesicles. Cell. 1994 Sep 23;78(6):937–948. doi: 10.1016/0092-8674(94)90270-4. [DOI] [PubMed] [Google Scholar]
  45. Trimble W. S., Cowan D. M., Scheller R. H. VAMP-1: a synaptic vesicle-associated integral membrane protein. Proc Natl Acad Sci U S A. 1988 Jun;85(12):4538–4542. doi: 10.1073/pnas.85.12.4538. [DOI] [PMC free article] [PubMed] [Google Scholar]
  46. Walworth N. C., Goud B., Kabcenell A. K., Novick P. J. Mutational analysis of SEC4 suggests a cyclical mechanism for the regulation of vesicular traffic. EMBO J. 1989 Jun;8(6):1685–1693. doi: 10.1002/j.1460-2075.1989.tb03560.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  47. Wilson D. W., Wilcox C. A., Flynn G. C., Chen E., Kuang W. J., Henzel W. J., Block M. R., Ullrich A., Rothman J. E. A fusion protein required for vesicle-mediated transport in both mammalian cells and yeast. Nature. 1989 Jun 1;339(6223):355–359. doi: 10.1038/339355a0. [DOI] [PubMed] [Google Scholar]
  48. Ziman M., Preuss D., Mulholland J., O'Brien J. M., Botstein D., Johnson D. I. Subcellular localization of Cdc42p, a Saccharomyces cerevisiae GTP-binding protein involved in the control of cell polarity. Mol Biol Cell. 1993 Dec;4(12):1307–1316. doi: 10.1091/mbc.4.12.1307. [DOI] [PMC free article] [PubMed] [Google Scholar]

Articles from The Journal of Cell Biology are provided here courtesy of The Rockefeller University Press

RESOURCES