The world's first wiki where authorship really matters (Nature Genetics, 2008). Due credit and reputation for authors. Imagine a global collaborative knowledge base for original thoughts. Search thousands of articles and collaborate with scientists around the globe.

wikigene or wiki gene protein drug chemical gene disease author authorship tracking collaborative publishing evolutionary knowledge reputation system wiki2.0 global collaboration genes proteins drugs chemicals diseases compound
Hoffmann, R. A wiki for the life sciences where authorship matters. Nature Genetics (2008)



Gene Review

SEC7  -  Sec7p

Saccharomyces cerevisiae S288c

Synonyms: Protein transport protein SEC7, YD9395.01C, YD9489.05C, YDR170C
Welcome! If you are familiar with the subject of this article, you can contribute to this open access knowledge base by deleting incorrect information, restructuring or completely rewriting any text. Read more.

Disease relevance of SEC7

  • The His6-tagged Sec7 domain from ySec7p (rySec7d) synthesized in Escherichia coli enhanced binding of guanosine 5'-[gamma-[35S]thio]triphosphate by recombinant yeast ARF1 (ryARF1) and ryARF2 but not by ryARF3 [1].

High impact information on SEC7

  • EMB30 is essential for normal cell division, cell expansion, and cell adhesion in Arabidopsis and encodes a protein that has similarity to Sec7 [2].
  • Vps1p-specific antibody labels punctate cytoplasmic structures that condense to larger structures in a Golgi-accumulating sec7 mutant; thus, Vps1p may associate with an intermediate organelle of the secretory pathway [3].
  • The glycosylated precursor first experiences proteolytic processing when accumulated in a mutant (sec7) blocked at the stage of the Golgi apparatus [4].
  • Gea1 contains a domain that is similar to a domain of Sec7, a protein necessary for intra-Golgi transport [5].
  • Mutations in the yeast SEC7 gene disrupt protein transport in the secretory pathway at the nonpermissive temperature [6].

Biological context of SEC7

  • A single copy of the authentic SEC7 gene permits growth of mutant cells, whereas the other gene suppresses growth deficiency only when expressed from a multicopy plasmid [7].
  • These results suggest a requirement for Sec7p cycling on and off of the membranes for cell growth and vesicular traffic [8].
  • To identify mammalian homologs of Sec7p and its interacting proteins, we used a genetic selection strategy in which a human HepG2 cDNA library was transformed into conditional-lethal yeast sec7 mutants [8].
  • Yeast Ysl2p, homologous to Sec7 domain guanine nucleotide exchange factors, functions in endocytosis and maintenance of vacuole integrity and interacts with the Arf-Like small GTPase Arl1p [9].
  • We show that the target of BFA inhibition of ARF exchange activity is an ARF-GDP-Sec7 domain protein complex, and that BFA acts to stabilize this complex to a greater extent for a BFA-sensitive Sec7 domain than for a resistant one [10].

Anatomical context of SEC7


Associations of SEC7 with chemical compounds

  • Interestingly, the Sec7 domain activity is inhibited by brefeldin A (BFA), a fungal metabolite that inhibits some of the Arf-GEFs, indicating that this domain is a target for BFA [14].
  • Conversion of A into B was also prevented in sec7 cells by the presence of dinitrophenol, a poison that depletes ATP levels, indicating that processing is dependent upon intracellular transport which involves ER --> Golgi and/or, at least, one intra-Golgi step(s) [12].
  • When the supply of newly synthesized exoglucanase was prevented by the addition of cycloheximide, the accumulated A was transformed into B in the presence of altered Sec7p that still prevented secretion [12].
  • Brefeldin A acts to stabilize an abortive ARF-GDP-Sec7 domain protein complex: involvement of specific residues of the Sec7 domain [10].
  • The addition of mannose is completely abolished in the early secretory mutant sec53, attenuated in the late-endoplasmic reticulum-blocked sec18, and unaffected in sec7, which is blocked late in the Golgi phase of secretion [15].

Physical interactions of SEC7

  • A 50-amino acid region near the Sec7 C terminus is required for Rsp5 binding and for normal Sec7 localization [16].

Co-localisations of SEC7

  • Ric1p largely colocalizes with the late Golgi marker Sec7p [17].
  • Furthermore, we demonstrate that Trs120p largely colocalizes with the late Golgi marker Sec7p [18].

Other interactions of SEC7

  • In double-immunofluorescence labeling experiments, significant colocalization of Sec7 and Kex2 proteins was found [19].
  • The GFP-Ysl2p staining is sensitive to a mutation in VPS27 resulting in the formation of an aberrant class E compartment, but it is not affected by a sec7 mutation [9].
  • However, PMR1 shows only partial colocalization with known Golgi markers, KEX2 and SEC7, in double-label immunofluorescence experiments [20].
  • Several proteins that belong to the Sec7-domain family, including the yeast Gea1p, have recently been shown to stimulate nucleotide exchange by Arf GTPases [14].
  • Soluble fractions prepared from temperature-sensitive mutants revealed requirements for the Ypt1p, Sec19p, Sly1p, Sec7p, and Uso1 proteins [21].

Analytical, diagnostic and therapeutic context of SEC7


  1. Brefeldin A-inhibited guanine nucleotide-exchange activity of Sec7 domain from yeast Sec7 with yeast and mammalian ADP ribosylation factors. Sata, M., Donaldson, J.G., Moss, J., Vaughan, M. Proc. Natl. Acad. Sci. U.S.A. (1998) [Pubmed]
  2. EMB30 is essential for normal cell division, cell expansion, and cell adhesion in Arabidopsis and encodes a protein that has similarity to Sec7. Shevell, D.E., Leu, W.M., Gillmor, C.S., Xia, G., Feldmann, K.A., Chua, N.H. Cell (1994) [Pubmed]
  3. A putative GTP binding protein homologous to interferon-inducible Mx proteins performs an essential function in yeast protein sorting. Rothman, J.H., Raymond, C.K., Gilbert, T., O'Hara, P.J., Stevens, T.H. Cell (1990) [Pubmed]
  4. Glycosylation and processing of prepro-alpha-factor through the yeast secretory pathway. Julius, D., Schekman, R., Thorner, J. Cell (1984) [Pubmed]
  5. Nucleotide exchange on ARF mediated by yeast Gea1 protein. Peyroche, A., Paris, S., Jackson, C.L. Nature (1996) [Pubmed]
  6. Immuno-isolation of Sec7p-coated transport vesicles from the yeast secretory pathway. Franzusoff, A., Lauzé, E., Howell, K.E. Nature (1992) [Pubmed]
  7. SEC7 encodes an unusual, high molecular weight protein required for membrane traffic from the yeast Golgi apparatus. Achstetter, T., Franzusoff, A., Field, C., Schekman, R. J. Biol. Chem. (1988) [Pubmed]
  8. Human ARF4 expression rescues sec7 mutant yeast cells. Deitz, S.B., Wu, C., Silve, S., Howell, K.E., Melançon, P., Kahn, R.A., Franzusoff, A. Mol. Cell. Biol. (1996) [Pubmed]
  9. Yeast Ysl2p, homologous to Sec7 domain guanine nucleotide exchange factors, functions in endocytosis and maintenance of vacuole integrity and interacts with the Arf-Like small GTPase Arl1p. Jochum, A., Jackson, D., Schwarz, H., Pipkorn, R., Singer-Krüger, B. Mol. Cell. Biol. (2002) [Pubmed]
  10. Brefeldin A acts to stabilize an abortive ARF-GDP-Sec7 domain protein complex: involvement of specific residues of the Sec7 domain. Peyroche, A., Antonny, B., Robineau, S., Acker, J., Cherfils, J., Jackson, C.L. Mol. Cell (1999) [Pubmed]
  11. Cloning and sequencing of a human cDNA from cytolytic NK/T cells with homology to yeast SEC7. Liu, L., Pohajdak, B. Biochim. Biophys. Acta (1992) [Pubmed]
  12. In vivo processing of the precursor of the major exoglucanase by KEX2 endoprotease in the Saccharomyces cerevisiae secretory pathway. Basco, R.D., Cueva, R., Andaluz, E., Larriba, G. Biochim. Biophys. Acta (1996) [Pubmed]
  13. Structure, biosynthesis, and localization of dipeptidyl aminopeptidase B, an integral membrane glycoprotein of the yeast vacuole. Roberts, C.J., Pohlig, G., Rothman, J.H., Stevens, T.H. J. Cell Biol. (1989) [Pubmed]
  14. Genetic interactions in yeast between Ypt GTPases and Arf guanine nucleotide exchangers. Jones, S., Jedd, G., Kahn, R.A., Franzusoff, A., Bartolini, F., Segev, N. Genetics (1999) [Pubmed]
  15. The yeast cell fusion protein FUS1 is O-glycosylated and spans the plasma membrane. Trueheart, J., Fink, G.R. Proc. Natl. Acad. Sci. U.S.A. (1989) [Pubmed]
  16. A C-terminal sequence in the guanine nucleotide exchange factor Sec7 mediates Golgi association and interaction with the Rsp5 ubiquitin ligase. Dehring, D.A., Adler, A.S., Hosseini, A., Hicke, L. J. Biol. Chem. (2008) [Pubmed]
  17. Ric1p and Rgp1p form a complex that catalyses nucleotide exchange on Ypt6p. Siniossoglou, S., Peak-Chew, S.Y., Pelham, H.R. EMBO J. (2000) [Pubmed]
  18. Mutants in trs120 disrupt traffic from the early endosome to the late Golgi. Cai, H., Zhang, Y., Pypaert, M., Walker, L., Ferro-Novick, S. J. Cell Biol. (2005) [Pubmed]
  19. Localization of components involved in protein transport and processing through the yeast Golgi apparatus. Franzusoff, A., Redding, K., Crosby, J., Fuller, R.S., Schekman, R. J. Cell Biol. (1991) [Pubmed]
  20. The yeast Ca(2+)-ATPase homologue, PMR1, is required for normal Golgi function and localizes in a novel Golgi-like distribution. Antebi, A., Fink, G.R. Mol. Biol. Cell (1992) [Pubmed]
  21. Biochemical requirements for the targeting and fusion of ER-derived transport vesicles with purified yeast Golgi membranes. Lupashin, V.V., Hamamoto, S., Schekman, R.W. J. Cell Biol. (1996) [Pubmed]
  22. Yeast Kex1p is a Golgi-associated membrane protein: deletions in a cytoplasmic targeting domain result in mislocalization to the vacuolar membrane. Cooper, A., Bussey, H. J. Cell Biol. (1992) [Pubmed]
  23. Modulation of the Golgi apparatus in Saccharomyces cerevisiae sec7 mutants as seen by three-dimensional electron microscopy. Rambourg, A., Clermont, Y., Képès, F. Anat. Rec. (1993) [Pubmed]
WikiGenes - Universities