The protein encoded by this gene is a zinc fingertranscription factor that binds to GC-rich motifs of many promoters. The encoded protein is involved in many cellular processes, including cell differentiation, cell growth, apoptosis, immune responses, response to DNA damage, and chromatin remodeling. Post-translational modifications such as phosphorylation, acetylation, glycosylation, and proteolytic processing significantly affect the activity of this protein, which can be an activator or a repressor.[1]
In the SV40 virus, Sp1 binds to the GC boxes in the regulatory region (RR) of the genome.
Structure
SP1 belongs to the Sp/KLF family of transcription factors. The protein is 785 amino acids long, with a molecular weight of 81 kDA. The SP1 transcription factor contains a zinc finger protein motif, by which it binds directly to DNA and enhances gene transcription. Its zinc fingers are of the Cys2/His2 type and bind the consensus sequence 5'-(G/T)GGGCGG(G/A)(G/A)(C/T)-3' (GC box element).
Applications
Sp1 has been used as a control protein to compare with when studying the increase or decrease of the aryl hydrocarbon receptor and/or the estrogen receptor, since it binds to both and generally remains at a relatively constant level.[2]
↑ 4.04.1Di Padova M, Bruno T, De Nicola F, Iezzi S, D'Angelo C, Gallo R, Nicosia D, Corbi N, Biroccio A, Floridi A, Passananti C, Fanciulli M (2003). "Che-1 arrests human colon carcinoma cell proliferation by displacing HDAC1 from the p21WAF1/CIP1 promoter". J. Biol. Chem. 278 (38): 36496–504. doi:10.1074/jbc.M306694200. PMID12847090.
↑Liu YW, Tseng HP, Chen LC, Chen BK, Chang WC (2003). "Functional cooperation of simian virus 40 promoter factor 1 and CCAAT/enhancer-binding protein beta and delta in lipopolysaccharide-induced gene activation of IL-10 in mouse macrophages". J. Immunol. 171 (2): 821–8. doi:10.4049/jimmunol.171.2.821. PMID12847250.
↑Rotheneder H, Geymayer S, Haidweger E (1999). "Transcription factors of the Sp1 family: interaction with E2F and regulation of the murine thymidine kinase promoter". J. Mol. Biol. 293 (5): 1005–15. doi:10.1006/jmbi.1999.3213. PMID10547281.
↑Galvagni F, Capo S, Oliviero S (2001). "Sp1 and Sp3 physically interact and co-operate with GABP for the activation of the utrophin promoter". J. Mol. Biol. 306 (5): 985–96. doi:10.1006/jmbi.2000.4335. PMID11237613.
↑Singh J, Murata K, Itahana Y, Desprez PY (2002). "Constitutive expression of the Id-1 promoter in human metastatic breast cancer cells is linked with the loss of NF-1/Rb/HDAC-1 transcription repressor complex". Oncogene. 21 (12): 1812–22. doi:10.1038/sj.onc.1205252. PMID11896613.
↑ 14.014.1Zhang Y, Dufau ML (2002). "Silencing of transcription of the human luteinizing hormone receptor gene by histone deacetylase-mSin3A complex". J. Biol. Chem. 277 (36): 33431–8. doi:10.1074/jbc.M204417200. PMID12091390.
↑ 15.015.1Sun JM, Chen HY, Moniwa M, Litchfield DW, Seto E, Davie JR (2002). "The transcriptional repressor Sp3 is associated with CK2-phosphorylated histone deacetylase 2". J. Biol. Chem. 277 (39): 35783–6. doi:10.1074/jbc.C200378200. PMID12176973.
↑Won J, Yim J, Kim TK (2002). "Sp1 and Sp3 recruit histone deacetylase to repress transcription of human telomerase reverse transcriptase (hTERT) promoter in normal human somatic cells". J. Biol. Chem. 277 (41): 38230–8. doi:10.1074/jbc.M206064200. PMID12151407.
↑ 17.017.1Gunther M, Laithier M, Brison O (2000). "A set of proteins interacting with transcription factor Sp1 identified in a two-hybrid screening". Mol. Cell. Biochem. 210 (1–2): 131–42. doi:10.1023/A:1007177623283. PMID10976766.
↑Botella LM, Sánchez-Elsner T, Sanz-Rodriguez F, Kojima S, Shimada J, Guerrero-Esteo M, Cooreman MP, Ratziu V, Langa C, Vary CP, Ramirez JR, Friedman S, Bernabéu C (2002). "Transcriptional activation of endoglin and transforming growth factor-beta signaling components by cooperative interaction between Sp1 and KLF6: their potential role in the response to vascular injury". Blood. 100 (12): 4001–10. doi:10.1182/blood.V100.12.4001. PMID12433697.
↑Krainc D, Bai G, Okamoto S, Carles M, Kusiak JW, Brent RN, Lipton SA (1998). "Synergistic activation of the N-methyl-D-aspartate receptor subunit 1 promoter by myocyte enhancer factor 2C and Sp1". J. Biol. Chem. 273 (40): 26218–24. doi:10.1074/jbc.273.40.26218. PMID9748305.
↑Park SY, Shin HM, Han TH (2002). "Synergistic interaction of MEF2D and Sp1 in activation of the CD14 promoter". Mol. Immunol. 39 (1–2): 25–30. doi:10.1016/S0161-5890(02)00055-X. PMID12213324.
↑ 27.027.127.2Wang YT, Chuang JY, Shen MR, Yang WB, Chang WC, Hung JJ (2008). "Sumoylation of specificity protein 1 augments its degradation by changing the localization and increasing the specificity protein 1 proteolytic process". J. Mol. Biol. 380 (5): 869–85. doi:10.1016/j.jmb.2008.05.043. PMID18572193.
↑Botella LM, Sánchez-Elsner T, Rius C, Corbí A, Bernabéu C (2001). "Identification of a critical Sp1 site within the endoglin promoter and its involvement in the transforming growth factor-beta stimulation". J. Biol. Chem. 276 (37): 34486–94. doi:10.1074/jbc.M011611200. PMID11432852.
↑Poncelet AC, Schnaper HW (2001). "Sp1 and Smad proteins cooperate to mediate transforming growth factor-beta 1-induced alpha 2(I) collagen expression in human glomerular mesangial cells". J. Biol. Chem. 276 (10): 6983–92. doi:10.1074/jbc.M006442200. PMID11114293.
↑Sugawara T, Saito M, Fujimoto S (2000). "Sp1 and SF-1 interact and cooperate in the regulation of human steroidogenic acute regulatory protein gene expression". Endocrinology. 141 (8): 2895–903. doi:10.1210/en.141.8.2895. PMID10919277.
↑Lécuyer E, Herblot S, Saint-Denis M, Martin R, Begley CG, Porcher C, Orkin SH, Hoang T (2002). "The SCL complex regulates c-kit expression in hematopoietic cells through functional interaction with Sp1". Blood. 100 (7): 2430–40. doi:10.1182/blood-2002-02-0568. PMID12239153.
Further reading
Dreier B, Beerli RR, Segal DJ, Flippin JD, Barbas CF (2001). "Development of zinc finger domains for recognition of the 5'-ANN-3' family of DNA sequences and their use in the construction of artificial transcription factors". J. Biol. Chem. 276 (31): 29466–78. doi:10.1074/jbc.M102604200. PMID11340073.
Tseng L, Gao J, Mazella J, Zhu HH, Lane B (1997). "Differentiation-dependent and cell-specific regulation of the hIGFBP-1 gene in human endometrium". Ann. N. Y. Acad. Sci. 828: 27–37. doi:10.1111/j.1749-6632.1997.tb48521.x. PMID9329821.
Zhang Y, Dufau ML (2003). "Dual mechanisms of regulation of transcription of luteinizing hormone receptor gene by nuclear orphan receptors and histone deacetylase complexes". J. Steroid Biochem. Mol. Biol. 85 (2–5): 401–14. doi:10.1016/S0960-0760(03)00230-9. PMID12943729.
Kino T, Pavlakis GN (2004). "Partner molecules of accessory protein Vpr of the human immunodeficiency virus type 1". DNA Cell Biol. 23 (4): 193–205. doi:10.1089/104454904773819789. PMID15142377.
Seelamgari A, Maddukuri A, Berro R, de la Fuente C, Kehn K, Deng L, Dadgar S, Bottazzi ME, Ghedin E, Pumfery A, Kashanchi F (2004). "Role of viral regulatory and accessory proteins in HIV-1 replication". Front. Biosci. 9: 2388–413. doi:10.2741/1403. PMID15353294.
Szpirer J, Szpirer C, Riviere M, Levan G, Marynen P, Cassiman JJ, Wiese R, DeLuca HF (1991). "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. 11 (1): 168–73. doi:10.1016/0888-7543(91)90114-T. PMID1662663.
Gumucio DL, Rood KL, Blanchard-McQuate KL, Gray TA, Saulino A, Collins FS (1991). "Interaction of Sp1 with the human gamma globin promoter: binding and transactivation of normal and mutant promoters". Blood. 78 (7): 1853–63. PMID1912570.
Courey AJ, Holtzman DA, Jackson SP, Tjian R (1989). "Synergistic activation by the glutamine-rich domains of human transcription factor Sp1". Cell. 59 (5): 827–36. doi:10.1016/0092-8674(89)90606-5. PMID2512012.
Jackson SP, Tjian R (1988). "O-glycosylation of eukaryotic transcription factors: implications for mechanisms of transcriptional regulation". Cell. 55 (1): 125–33. doi:10.1016/0092-8674(88)90015-3. PMID3139301.
Kadonaga JT, Carner KR, Masiarz FR, Tjian R (1987). "Isolation of cDNA encoding transcription factor Sp1 and functional analysis of the DNA binding domain". Cell. 51 (6): 1079–90. doi:10.1016/0092-8674(87)90594-0. PMID3319186.
Zhang R, Min W, Sessa WC (1995). "Functional analysis of the human endothelial nitric oxide synthase promoter. Sp1 and GATA factors are necessary for basal transcription in endothelial cells". J. Biol. Chem. 270 (25): 15320–6. doi:10.1074/jbc.270.25.15320. PMID7541039.
Hagen G, Dennig J, Preiss A, Beato M, Suske G (1995). "Functional analyses of the transcription factor Sp4 reveal properties distinct from Sp1 and Sp3". J. Biol. Chem. 270 (42): 24989–94. doi:10.1074/jbc.270.42.24989. PMID7559627.
Wang L, Mukherjee S, Jia F, Narayan O, Zhao LJ (1995). "Interaction of virion protein Vpr of human immunodeficiency virus type 1 with cellular transcription factor Sp1 and trans-activation of viral long terminal repeat". J. Biol. Chem. 270 (43): 25564–9. doi:10.1074/jbc.270.43.25564. PMID7592727.
Howcroft TK, Palmer LA, Brown J, Rellahan B, Kashanchi F, Brady JN, Singer DS (1995). "HIV Tat represses transcription through Sp1-like elements in the basal promoter". Immunity. 3 (1): 127–38. doi:10.1016/1074-7613(95)90165-5. PMID7621073.
Ferrari N, Desmarais D, Royal A (1995). "Transcriptional activation of the neuronal peripherin-encoding gene depends on a G + C-rich element that binds Sp1 in vitro and in vivo". Gene. 159 (2): 159–65. doi:10.1016/0378-1119(95)00140-2. PMID7622044.
Tan NY, Midgley VC, Kavurma MM, Santiago FS, Luo X, Peden R, Fahmy RG, Berndt MC, Molloy MP, Khachigian LM (2008). "Angiotensin II-inducible platelet-derived growth factor-D transcription requires specific Ser/Thr residues in the second zinc finger region of Sp1". Circ. Res. 102 (4): e38–51. doi:10.1161/CIRCRESAHA.107.167395. PMID18258854.