Skip to main content
NCBI home page
Nucleic Acids Research logoLink to Nucleic Acids Research
. 1992 Jul 25;20(14):3721–3724. doi: 10.1093/nar/20.14.3721

Role of the conserved leucines in the leucine zipper dimerization motif of yeast GCN4.

W J van Heeckeren 1, J W Sellers 1, K Struhl 1
PMCID: PMC334023  PMID: 1641337

Abstract

Yeast GCN4 belongs to the class of eukaryotic transcription factors whose bZIP DNA-binding domains dimerize via a leucine zipper motif that structurally resembles a coiled coil. The leucine zipper contains 4-5 highly conserved leucine residues spaced exactly 7 residues apart that are located within the alpha-helical hydrophobic interface between protein monomers. Here, we investigate the role of the four canonical leucines in the GCN4 leucine zipper by analyzing a series of mutated derivatives for their ability to activate transcription in vivo and to bind DNA in vitro. The GCN4 leucine zipper is surprisingly tolerant of mutations, with a wide variety of single substitutions at any of the four leucines including basic and acidic amino acids behaving indistinguishably from wild-type GCN4. Moreover, some derivatives containing two leucine substitutions display detectable though reduced function. These results indicate that other residues within the coiled coil are crucial for efficient dimerization, and they suggest that some eukaryotic transcriptional regulatory proteins lacking the conserved leucine repeat will dimerize through a structurally homologous motif. Interestingly, our results differ in several respects from those obtained by analyzing mutations in the GCN4 leucine zipper in the context of a lambda repressor-GCN4 zipper hybrid protein. These apparent differences may reflect a functional interrelationship between the leucine zipper and basic region subdomains for DNA-binding by bZIP proteins.

Full text

PDF
3721

Images in this article

3722Image
on p.3722
3723Image
on p.3723

Selected References

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

  1. Agre P., Johnson P. F., McKnight S. L. Cognate DNA binding specificity retained after leucine zipper exchange between GCN4 and C/EBP. Science. 1989 Nov 17;246(4932):922–926. doi: 10.1126/science.2530632. [DOI] [PubMed] [Google Scholar]
  2. Arndt K., Fink G. R. GCN4 protein, a positive transcription factor in yeast, binds general control promoters at all 5' TGACTC 3' sequences. Proc Natl Acad Sci U S A. 1986 Nov;83(22):8516–8520. doi: 10.1073/pnas.83.22.8516. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Gentz R., Rauscher F. J., 3rd, Abate C., Curran T. Parallel association of Fos and Jun leucine zippers juxtaposes DNA binding domains. Science. 1989 Mar 31;243(4899):1695–1699. doi: 10.1126/science.2494702. [DOI] [PubMed] [Google Scholar]
  4. Hill D. E., Hope I. A., Macke J. P., Struhl K. Saturation mutagenesis of the yeast his3 regulatory site: requirements for transcriptional induction and for binding by GCN4 activator protein. Science. 1986 Oct 24;234(4775):451–457. doi: 10.1126/science.3532321. [DOI] [PubMed] [Google Scholar]
  5. Hope I. A., Struhl K. Functional dissection of a eukaryotic transcriptional activator protein, GCN4 of yeast. Cell. 1986 Sep 12;46(6):885–894. doi: 10.1016/0092-8674(86)90070-x. [DOI] [PubMed] [Google Scholar]
  6. Hope I. A., Struhl K. GCN4 protein, synthesized in vitro, binds HIS3 regulatory sequences: implications for general control of amino acid biosynthetic genes in yeast. Cell. 1985 Nov;43(1):177–188. doi: 10.1016/0092-8674(85)90022-4. [DOI] [PubMed] [Google Scholar]
  7. Hope I. A., Struhl K. GCN4, a eukaryotic transcriptional activator protein, binds as a dimer to target DNA. EMBO J. 1987 Sep;6(9):2781–2784. doi: 10.1002/j.1460-2075.1987.tb02573.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. Hu J. C., O'Shea E. K., Kim P. S., Sauer R. T. Sequence requirements for coiled-coils: analysis with lambda repressor-GCN4 leucine zipper fusions. Science. 1990 Dec 7;250(4986):1400–1403. doi: 10.1126/science.2147779. [DOI] [PubMed] [Google Scholar]
  9. Kouzarides T., Ziff E. Leucine zippers of fos, jun and GCN4 dictate dimerization specificity and thereby control DNA binding. Nature. 1989 Aug 17;340(6234):568–571. doi: 10.1038/340568a0. [DOI] [PubMed] [Google Scholar]
  10. Kouzarides T., Ziff E. The role of the leucine zipper in the fos-jun interaction. Nature. 1988 Dec 15;336(6200):646–651. doi: 10.1038/336646a0. [DOI] [PubMed] [Google Scholar]
  11. 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]
  12. Landschulz W. H., Johnson P. F., McKnight S. L. The DNA binding domain of the rat liver nuclear protein C/EBP is bipartite. Science. 1989 Mar 31;243(4899):1681–1688. doi: 10.1126/science.2494700. [DOI] [PubMed] [Google Scholar]
  13. Landschulz W. H., Johnson P. F., McKnight S. L. The leucine zipper: a hypothetical structure common to a new class of DNA binding proteins. Science. 1988 Jun 24;240(4860):1759–1764. doi: 10.1126/science.3289117. [DOI] [PubMed] [Google Scholar]
  14. O'Neil K. T., Hoess R. H., DeGrado W. F. Design of DNA-binding peptides based on the leucine zipper motif. Science. 1990 Aug 17;249(4970):774–778. doi: 10.1126/science.2389143. [DOI] [PubMed] [Google Scholar]
  15. O'Shea E. K., Klemm J. D., Kim P. S., Alber T. X-ray structure of the GCN4 leucine zipper, a two-stranded, parallel coiled coil. Science. 1991 Oct 25;254(5031):539–544. doi: 10.1126/science.1948029. [DOI] [PubMed] [Google Scholar]
  16. O'Shea E. K., Rutkowski R., Kim P. S. Evidence that the leucine zipper is a coiled coil. Science. 1989 Jan 27;243(4890):538–542. doi: 10.1126/science.2911757. [DOI] [PubMed] [Google Scholar]
  17. O'Shea E. K., Rutkowski R., Stafford W. F., 3rd, Kim P. S. Preferential heterodimer formation by isolated leucine zippers from fos and jun. Science. 1989 Aug 11;245(4918):646–648. doi: 10.1126/science.2503872. [DOI] [PubMed] [Google Scholar]
  18. Oliphant A. R., Brandl C. J., Struhl K. Defining the sequence specificity of DNA-binding proteins by selecting binding sites from random-sequence oligonucleotides: analysis of yeast GCN4 protein. Mol Cell Biol. 1989 Jul;9(7):2944–2949. doi: 10.1128/mcb.9.7.2944. [DOI] [PMC free article] [PubMed] [Google Scholar]
  19. Patel L., Abate C., Curran T. Altered protein conformation on DNA binding by Fos and Jun. Nature. 1990 Oct 11;347(6293):572–575. doi: 10.1038/347572a0. [DOI] [PubMed] [Google Scholar]
  20. Pu W. T., Struhl K. Highly conserved residues in the bZIP domain of yeast GCN4 are not essential for DNA binding. Mol Cell Biol. 1991 Oct;11(10):4918–4926. doi: 10.1128/mcb.11.10.4918. [DOI] [PMC free article] [PubMed] [Google Scholar]
  21. Pu W. T., Struhl K. The leucine zipper symmetrically positions the adjacent basic regions for specific DNA binding. Proc Natl Acad Sci U S A. 1991 Aug 15;88(16):6901–6905. doi: 10.1073/pnas.88.16.6901. [DOI] [PMC free article] [PubMed] [Google Scholar]
  22. Rasmussen R., Benvegnu D., O'Shea E. K., Kim P. S., Alber T. X-ray scattering indicates that the leucine zipper is a coiled coil. Proc Natl Acad Sci U S A. 1991 Jan 15;88(2):561–564. doi: 10.1073/pnas.88.2.561. [DOI] [PMC free article] [PubMed] [Google Scholar]
  23. Schuermann M., Neuberg M., Hunter J. B., Jenuwein T., Ryseck R. P., Bravo R., Müller R. The leucine repeat motif in Fos protein mediates complex formation with Jun/AP-1 and is required for transformation. Cell. 1989 Feb 10;56(3):507–516. doi: 10.1016/0092-8674(89)90253-5. [DOI] [PubMed] [Google Scholar]
  24. Sellers J. W., Struhl K. Changing fos oncoprotein to a jun-independent DNA binding protein with GCN4 dimerization specificity by swapping "leucine zippers". Nature. 1989 Sep 7;341(6237):74–76. doi: 10.1038/341074a0. [DOI] [PubMed] [Google Scholar]
  25. Sellers J. W., Vincent A. C., Struhl K. Mutations that define the optimal half-site for binding yeast GCN4 activator protein and identify an ATF/CREB-like repressor that recognizes similar DNA sites. Mol Cell Biol. 1990 Oct;10(10):5077–5086. doi: 10.1128/mcb.10.10.5077. [DOI] [PMC free article] [PubMed] [Google Scholar]
  26. Talanian R. V., McKnight C. J., Kim P. S. Sequence-specific DNA binding by a short peptide dimer. Science. 1990 Aug 17;249(4970):769–771. doi: 10.1126/science.2389142. [DOI] [PubMed] [Google Scholar]
  27. Turner R., Tjian R. Leucine repeats and an adjacent DNA binding domain mediate the formation of functional cFos-cJun heterodimers. Science. 1989 Mar 31;243(4899):1689–1694. doi: 10.1126/science.2494701. [DOI] [PubMed] [Google Scholar]
  28. Weiss M. A., Ellenberger T., Wobbe C. R., Lee J. P., Harrison S. C., Struhl K. Folding transition in the DNA-binding domain of GCN4 on specific binding to DNA. Nature. 1990 Oct 11;347(6293):575–578. doi: 10.1038/347575a0. [DOI] [PubMed] [Google Scholar]

Articles from Nucleic Acids Research are provided here courtesy of Oxford University Press

RESOURCES