Skip to main content
PMC home page
Proceedings of the National Academy of Sciences of the United States of America logoLink to Proceedings of the National Academy of Sciences of the United States of America
. 1995 Sep 26;92(20):9107–9111. doi: 10.1073/pnas.92.20.9107

An alternatively spliced form of the transcription factor Sp1 containing only a single glutamine-rich transactivation domain.

S P Persengiev 1, J D Saffer 1, D L Kilpatrick 1
PMCID: PMC40933  PMID: 7568082

Abstract

Protein-protein interactions involving specific transactivation domains play a central role in gene transcription and its regulation. The promoter-specific transcription factor Sp1 contains two glutamine-rich transcriptional activation domains (A and B) that mediate direct interactions with the transcription factor TFIID complex associated with RNA polymerase II and synergistic effects involving multiple Sp1 molecules. In the present study, we report the complementary DNA sequence for an alternatively spliced form of mouse Sp1 (mSp1-S) that lacks one of the two glutamine-rich activation regions present in the full-length protein. Corresponding transcripts were identified in mouse tissues and cell lines, and an Sp1-related protein identical in size to that predicted for mSp1-S was detected in mouse nuclear extracts. Cotransfection analysis revealed that mSp1-S lacks appreciable activity at promoters containing a single Sp1 response element but is active when multiple Sp1 sites are present, suggesting synergistic interactions between multiple mSp1-S molecules. The absence of a single glutamine-rich domain does not fully explain the properties of the smaller protein and indicates that additional structural features account for its unique transcriptional activity. The functional implications of this alternatively spliced form of Sp1 are discussed.

Full text

PDF
9108

Images in this article

9109Fig. 2
on p.9109
9109Fig. 3
on p.9109
9109Fig. 4
on p.9109
9110Fig. 5
on p.9110

Selected References

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

  1. Bach I., Yaniv M. More potent transcriptional activators or a transdominant inhibitor of the HNF1 homeoprotein family are generated by alternative RNA processing. EMBO J. 1993 Nov;12(11):4229–4242. doi: 10.1002/j.1460-2075.1993.tb06107.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Brönner G., Chu-LaGraff Q., Doe C. Q., Cohen B., Weigel D., Taubert H., Jäckle H. Sp1/egr-like zinc-finger protein required for endoderm specification and germ-layer formation in Drosophila. Nature. 1994 Jun 23;369(6482):664–668. doi: 10.1038/369664a0. [DOI] [PubMed] [Google Scholar]
  3. Chen L. I., Nishinaka T., Kwan K., Kitabayashi I., Yokoyama K., Fu Y. H., Grünwald S., Chiu R. The retinoblastoma gene product RB stimulates Sp1-mediated transcription by liberating Sp1 from a negative regulator. Mol Cell Biol. 1994 Jul;14(7):4380–4389. doi: 10.1128/mcb.14.7.4380. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Chiang C. M., Roeder R. G. Cloning of an intrinsic human TFIID subunit that interacts with multiple transcriptional activators. Science. 1995 Jan 27;267(5197):531–536. doi: 10.1126/science.7824954. [DOI] [PubMed] [Google Scholar]
  5. Courey A. J., Holtzman D. A., Jackson S. P., Tjian R. Synergistic activation by the glutamine-rich domains of human transcription factor Sp1. Cell. 1989 Dec 1;59(5):827–836. doi: 10.1016/0092-8674(89)90606-5. [DOI] [PubMed] [Google Scholar]
  6. Courey A. J., Tjian R. Analysis of Sp1 in vivo reveals multiple transcriptional domains, including a novel glutamine-rich activation motif. Cell. 1988 Dec 2;55(5):887–898. doi: 10.1016/0092-8674(88)90144-4. [DOI] [PubMed] [Google Scholar]
  7. Delmas V., Laoide B. M., Masquilier D., de Groot R. P., Foulkes N. S., Sassone-Corsi P. Alternative usage of initiation codons in mRNA encoding the cAMP-responsive-element modulator generates regulators with opposite functions. Proc Natl Acad Sci U S A. 1992 May 15;89(10):4226–4230. doi: 10.1073/pnas.89.10.4226. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. Drapkin R., Reardon J. T., Ansari A., Huang J. C., Zawel L., Ahn K., Sancar A., Reinberg D. Dual role of TFIIH in DNA excision repair and in transcription by RNA polymerase II. Nature. 1994 Apr 21;368(6473):769–772. doi: 10.1038/368769a0. [DOI] [PubMed] [Google Scholar]
  9. Foulkes N. S., Borrelli E., Sassone-Corsi P. CREM gene: use of alternative DNA-binding domains generates multiple antagonists of cAMP-induced transcription. Cell. 1991 Feb 22;64(4):739–749. doi: 10.1016/0092-8674(91)90503-q. [DOI] [PubMed] [Google Scholar]
  10. Foulkes N. S., Mellström B., Benusiglio E., Sassone-Corsi P. Developmental switch of CREM function during spermatogenesis: from antagonist to activator. Nature. 1992 Jan 2;355(6355):80–84. doi: 10.1038/355080a0. [DOI] [PubMed] [Google Scholar]
  11. Galcheva-Gargova Z., Tokeson J. P., Karagyosov L. K., Ebert K. M., Kilpatrick D. L. The rat proenkephalin germ line promoter contains multiple binding sites for spermatogenic cell nuclear proteins. Mol Endocrinol. 1993 Aug;7(8):979–991. doi: 10.1210/mend.7.8.8232318. [DOI] [PubMed] [Google Scholar]
  12. Gill G., Pascal E., Tseng Z. H., Tjian R. A glutamine-rich hydrophobic patch in transcription factor Sp1 contacts the dTAFII110 component of the Drosophila TFIID complex and mediates transcriptional activation. Proc Natl Acad Sci U S A. 1994 Jan 4;91(1):192–196. doi: 10.1073/pnas.91.1.192. [DOI] [PMC free article] [PubMed] [Google Scholar]
  13. Gogos J. A., Hsu T., Bolton J., Kafatos F. C. Sequence discrimination by alternatively spliced isoforms of a DNA binding zinc finger domain. Science. 1992 Sep 25;257(5078):1951–1955. doi: 10.1126/science.1290524. [DOI] [PubMed] [Google Scholar]
  14. Hoey T., Weinzierl R. O., Gill G., Chen J. L., Dynlacht B. D., Tjian R. Molecular cloning and functional analysis of Drosophila TAF110 reveal properties expected of coactivators. Cell. 1993 Jan 29;72(2):247–260. doi: 10.1016/0092-8674(93)90664-c. [DOI] [PubMed] [Google Scholar]
  15. Imataka H., Sogawa K., Yasumoto K., Kikuchi Y., Sasano K., Kobayashi A., Hayami M., Fujii-Kuriyama Y. Two regulatory proteins that bind to the basic transcription element (BTE), a GC box sequence in the promoter region of the rat P-4501A1 gene. EMBO J. 1992 Oct;11(10):3663–3671. doi: 10.1002/j.1460-2075.1992.tb05451.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  16. Jackson S. P., MacDonald J. J., Lees-Miller S., Tjian R. GC box binding induces phosphorylation of Sp1 by a DNA-dependent protein kinase. Cell. 1990 Oct 5;63(1):155–165. doi: 10.1016/0092-8674(90)90296-q. [DOI] [PubMed] [Google Scholar]
  17. Jackson S. P., MacDonald J. J., Lees-Miller S., Tjian R. GC box binding induces phosphorylation of Sp1 by a DNA-dependent protein kinase. Cell. 1990 Oct 5;63(1):155–165. doi: 10.1016/0092-8674(90)90296-q. [DOI] [PubMed] [Google Scholar]
  18. Jackson S. P., Tjian R. O-glycosylation of eukaryotic transcription factors: implications for mechanisms of transcriptional regulation. Cell. 1988 Oct 7;55(1):125–133. doi: 10.1016/0092-8674(88)90015-3. [DOI] [PubMed] [Google Scholar]
  19. Kadonaga J. T., Carner K. R., Masiarz F. R., Tjian R. Isolation of cDNA encoding transcription factor Sp1 and functional analysis of the DNA binding domain. Cell. 1987 Dec 24;51(6):1079–1090. doi: 10.1016/0092-8674(87)90594-0. [DOI] [PubMed] [Google Scholar]
  20. Kilpatrick D. L., Zinn S. A., Fitzgerald M., Higuchi H., Sabol S. L., Meyerhardt J. Transcription of the rat and mouse proenkephalin genes is initiated at distinct sites in spermatogenic and somatic cells. Mol Cell Biol. 1990 Jul;10(7):3717–3726. doi: 10.1128/mcb.10.7.3717. [DOI] [PMC free article] [PubMed] [Google Scholar]
  21. Kim S. J., Onwuta U. S., Lee Y. I., Li R., Botchan M. R., Robbins P. D. The retinoblastoma gene product regulates Sp1-mediated transcription. Mol Cell Biol. 1992 Jun;12(6):2455–2463. doi: 10.1128/mcb.12.6.2455. [DOI] [PMC free article] [PubMed] [Google Scholar]
  22. Kozmik Z., Kurzbauer R., Dörfler P., Busslinger M. Alternative splicing of Pax-8 gene transcripts is developmentally regulated and generates isoforms with different transactivation properties. Mol Cell Biol. 1993 Oct;13(10):6024–6035. doi: 10.1128/mcb.13.10.6024. [DOI] [PMC free article] [PubMed] [Google Scholar]
  23. Lee J. S., Galvin K. M., Shi Y. Evidence for physical interaction between the zinc-finger transcription factors YY1 and Sp1. Proc Natl Acad Sci U S A. 1993 Jul 1;90(13):6145–6149. doi: 10.1073/pnas.90.13.6145. [DOI] [PMC free article] [PubMed] [Google Scholar]
  24. Molina C. A., Foulkes N. S., Lalli E., Sassone-Corsi P. Inducibility and negative autoregulation of CREM: an alternative promoter directs the expression of ICER, an early response repressor. Cell. 1993 Dec 3;75(5):875–886. doi: 10.1016/0092-8674(93)90532-u. [DOI] [PubMed] [Google Scholar]
  25. Pascal E., Tjian R. Different activation domains of Sp1 govern formation of multimers and mediate transcriptional synergism. Genes Dev. 1991 Sep;5(9):1646–1656. doi: 10.1101/gad.5.9.1646. [DOI] [PubMed] [Google Scholar]
  26. Rivier D. H., Rine J. An origin of DNA replication and a transcription silencer require a common element. Science. 1992 May 1;256(5057):659–663. doi: 10.1126/science.1585179. [DOI] [PubMed] [Google Scholar]
  27. Saffer J. D., Thurston S. J., Annarella M. B., Compton J. G. Localization of the gene for the trans-acting transcription factor Sp1 to the distal end of mouse chromosome 15. Genomics. 1990 Nov;8(3):571–574. doi: 10.1016/0888-7543(90)90046-w. [DOI] [PubMed] [Google Scholar]
  28. Seed B., Sheen J. Y. A simple phase-extraction assay for chloramphenicol acyltransferase activity. Gene. 1988 Jul 30;67(2):271–277. doi: 10.1016/0378-1119(88)90403-9. [DOI] [PubMed] [Google Scholar]
  29. Szpirer J., Szpirer C., Riviere M., Levan G., Marynen P., Cassiman J. J., Wiese R., DeLuca H. F. The Sp1 transcription factor gene (SP1) and the 1,25-dihydroxyvitamin D3 receptor gene (VDR) are colocalized on human chromosome arm 12q and rat chromosome 7. Genomics. 1991 Sep;11(1):168–173. doi: 10.1016/0888-7543(91)90114-t. [DOI] [PubMed] [Google Scholar]
  30. Takeda H., Matsuzaki T., Oki T., Miyagawa T., Amanuma H. A novel POU domain gene, zebrafish pou2: expression and roles of two alternatively spliced twin products in early development. Genes Dev. 1994 Jan;8(1):45–59. doi: 10.1101/gad.8.1.45. [DOI] [PubMed] [Google Scholar]
  31. Theill L. E., Castrillo J. L., Wu D., Karin M. Dissection of functional domains of the pituitary-specific transcription factor GHF-1. Nature. 1989 Dec 21;342(6252):945–948. doi: 10.1038/342945a0. [DOI] [PubMed] [Google Scholar]
  32. Wimmer E. A., Jäckle H., Pfeifle C., Cohen S. M. A Drosophila homologue of human Sp1 is a head-specific segmentation gene. Nature. 1993 Dec 16;366(6456):690–694. doi: 10.1038/366690a0. [DOI] [PubMed] [Google Scholar]

Articles from Proceedings of the National Academy of Sciences of the United States of America are provided here courtesy of National Academy of Sciences

RESOURCES