Sp1 in Astrocyte Is Important for Neurite Outgrowth and Synaptogenesis

  • Chia-Yang Hung
  • Tsung-I Hsu
  • Jian-Ying Chuang
  • Tsung-Ping Su
  • Wen-Chang Chang
  • Jan-Jong HungEmail author


In this study, we found that Sp1 was highly expressed in astrocytes, implying that Sp1 might be important for the function of astrocytes. Sp1/GFAP-Cre-ERT2 conditional knockout mice were constructed to study the role of Sp1 in astrocytes. Knockout of Sp1 in astrocytes altered astrocytic morphology and decreased GFAP expression in the cortex and hippocampus but did not affect cell viability. Loss of Sp1 in astrocytes decreased the number of neurons in the cortex and hippocampus. Conditioned medium from primary astrocytes with Sp1 knockout disrupted neuronal dendritic outgrowth and synapse formation, resulting in abnormal learning, memory, and motor behavior. Sp1 knockout in astrocytes altered gene expression, including decreasing the expression of Toll-like receptor 2 and Cfb and increasing the expression of C1q and C4Bp, thereby affecting neurite outgrowth and synapse formation, resulting in disordered neuron function. Studying these gene regulations might be beneficial to understanding neuronal development and brain injury prevention.


Sp1 Astrocyte Neurite outgrowth Synaptogenesis 



We are grateful for the support of clinical specimens from the Human Biobank, Research Center of Clinical Medicine, and National Cheng Kung University Hospital.

Funding Information

This work was supported by the grants (106-2320-B-006-065-MY3, 106-2320-B-006-020-MY3, and 104-2923-B-038-002-MY3) obtained from the Ministry of Science and Technology, Taiwan.

Supplementary material

12035_2019_1694_MOESM1_ESM.jpg (468 kb)
Supplementary figure 1 Sp1 expression level in Sp1 knockout mice. Wild type, Sp1f/+ and Sp1f/f mice were treated with tamoxifen and then sacrificed. The Sp1 level was studied by Western blot with anti-Sp1 antibodies. The Sp1 level was quantified and statistical assay by t-test, *<0.05, **<0.01. (JPG 467 kb)
12035_2019_1694_MOESM2_ESM.jpg (760 kb)
Supplementary figure 2 Sp1-mediated pathway and molecular function in astrocyte. Sp1 was knockout from astrocyte by tamoxifen treatment, and then the RNA was isolated for performing the cDNA array. The gene expression involved in pathways (A) and molecular function (B) was analysis by Gene Ontology analysis. (JPG 760 kb)
12035_2019_1694_MOESM3_ESM.jpg (1 mb)
Supplementary figure 3 Sp1 in astrocyte regulates the pathways and various biological processes in neurons. Conditional medium was collected from wild type astrocyte or Sp1 knockout astrocyte, and then treated the neurons. The RNA was isolated for performing the cDNA array. The gene expression involved in pathways (A) and biological processes (B) was analysis by Gene Ontology analysis. (JPG 1038 kb)
12035_2019_1694_MOESM4_ESM.jpg (1 mb)
Supplementary figure 4 Sp1 in astrocyte regulates the group of proteins in neurons. The proteomic clusters was analyzed in neuron treated with conditional medium from astrocytes with or without Sp1 knockout. (JPG 1042 kb)


  1. 1.
    Li L, Davie JR (2010) The role of Sp1 and Sp3 in normal and cancer cell biology. Ann Anat 192(5):275–283. CrossRefGoogle Scholar
  2. 2.
    Wang SA, Chuang JY, Yeh SH, Wang YT, Liu YW, Chang WC, Hung JJ (2009) Heat shock protein 90 is important for Sp1 stability during mitosis. J Mol Biol 387(5):1106–1119. CrossRefGoogle Scholar
  3. 3.
    Lagger G, Doetzlhofer A, Schuettengruber B, Haidweger E, Simboeck E, Tischler J, Chiocca S, Suske G et al (2003) The tumor suppressor p53 and histone deacetylase 1 are antagonistic regulators of the cyclin-dependent kinase inhibitor p21/WAF1/CIP1 gene. Mol Cell Biol 23(8):2669–2679CrossRefGoogle Scholar
  4. 4.
    Opitz OG, Rustgi AK (2000) Interaction between Sp1 and cell cycle regulatory proteins is important in transactivation of a differentiation-related gene. Cancer Res 60(11):2825–2830Google Scholar
  5. 5.
    Wei C, Zhang W, Zhou Q, Zhao C, Du Y, Yan Q, Li Z, Miao J (2016) Mithramycin A alleviates cognitive deficits and reduces neuropathology in a transgenic mouse model of Alzheimer’s disease. Neurochem Res 41(8):1924–1938. CrossRefGoogle Scholar
  6. 6.
    Wang J, Song W (2016) Regulation of LRRK2 promoter activity and gene expression by Sp1. Mol Brain 9:33. CrossRefGoogle Scholar
  7. 7.
    Citron BA, Saykally JN, Cao C, Dennis JS, Runfeldt M, Arendash GW (2015) Transcription factor Sp1 inhibition, memory, and cytokines in a mouse model of Alzheimer’s disease. Am J Neurodegener Dis 4(2):40–48Google Scholar
  8. 8.
    Chuang JY, Kao TJ, Lin SH, Wu AC, Lee PT, Su TP, Yeh SH, Lee YC et al (2017) Specificity protein 1-zinc finger protein 179 pathway is involved in the attenuation of oxidative stress following brain injury. Redox Biol 11:135–143. CrossRefGoogle Scholar
  9. 9.
    Miras-Portugal MT, Gomez-Villafuertes R, Gualix J, Diaz-Hernandez JI, Artalejo AR, Ortega F, Delicado EG, Perez-Sen R (2016) Nucleotides in neuroregeneration and neuroprotection. Neuropharmacology 104:243–254. CrossRefGoogle Scholar
  10. 10.
    Simard JM, Chen M, Tarasov KV, Bhatta S, Ivanova S, Melnitchenko L, Tsymbalyuk N, West GA et al (2006) Newly expressed SUR1-regulated NC(Ca-ATP) channel mediates cerebral edema after ischemic stroke. Nat Med 12(4):433–440. CrossRefGoogle Scholar
  11. 11.
    Yeh SH, Yang WB, Gean PW, Hsu CY, Tseng JT, Su TP, Chang WC, Hung JJ (2011) Translational and transcriptional control of Sp1 against ischaemia through a hydrogen peroxide-activated internal ribosomal entry site pathway. Nucleic Acids Res 39(13):5412–5423. CrossRefGoogle Scholar
  12. 12.
    Eroglu C, Barres BA (2010) Regulation of synaptic connectivity by glia. Nature 468(7321):223–231. CrossRefGoogle Scholar
  13. 13.
    Chung WS, Allen NJ, Eroglu C (2015) Astrocytes control synapse formation, function, and elimination. Cold Spring Harb Perspect Biol 7(9):a020370. CrossRefGoogle Scholar
  14. 14.
    Malarkey EB, Parpura V (2008) Mechanisms of glutamate release from astrocytes. Neurochem Int 52(1–2):142–154. CrossRefGoogle Scholar
  15. 15.
    Haydon PG, Carmignoto G (2006) Astrocyte control of synaptic transmission and neurovascular coupling. Physiol Rev 86(3):1009–1031. CrossRefGoogle Scholar
  16. 16.
    Allen NJ, Eroglu C (2017) Cell biology of astrocyte-synapse interactions. Neuron 96(3):697–708. CrossRefGoogle Scholar
  17. 17.
    Li B, Chen P, Qu J, Shi L, Zhuang W, Fu J, Li J, Zhang X et al (2014) Activation of LTBP3 gene by a long noncoding RNA (lncRNA) MALAT1 transcript in mesenchymal stem cells from multiple myeloma. J Biol Chem 289(42):29365–29375. CrossRefGoogle Scholar
  18. 18.
    Yang WB, Chen PH, Hsu TS, Fu TF, Su WC, Liaw H, Chang WC, Hung JJ (2014) Sp1-mediated microRNA-182 expression regulates lung cancer progression. Oncotarget 5(3):740–753. CrossRefGoogle Scholar
  19. 19.
    Kruger I, Vollmer M, Simmons DG, Elsasser HP, Philipsen S, Suske G (2007) Sp1/Sp3 compound heterozygous mice are not viable: impaired erythropoiesis and severe placental defects. Dev Dyn 236(8):2235–2244. CrossRefGoogle Scholar
  20. 20.
    Marin M, Karis A, Visser P, Grosveld F, Philipsen S (1997) Transcription factor Sp1 is essential for early embryonic development but dispensable for cell growth and differentiation. Cell 89(4):619–628CrossRefGoogle Scholar
  21. 21.
    Michinaga S, Ishida A, Takeuchi R, Koyama Y (2013) Endothelin-1 stimulates cyclin D1 expression in rat cultured astrocytes via activation of Sp1. Neurochem Int 63(1):25–34. CrossRefGoogle Scholar
  22. 22.
    Jin M, Ande A, Kumar A, Kumar S (2013) Regulation of cytochrome P450 2e1 expression by ethanol: role of oxidative stress-mediated pkc/jnk/sp1 pathway. Cell Death Dis 4:e554. CrossRefGoogle Scholar
  23. 23.
    Loeffler S, Fayard B, Weis J, Weissenberger J (2005) Interleukin-6 induces transcriptional activation of vascular endothelial growth factor (VEGF) in astrocytes in vivo and regulates VEGF promoter activity in glioblastoma cells via direct interaction between STAT3 and Sp1. Int J Cancer 115(2):202–213. CrossRefGoogle Scholar
  24. 24.
    Choi SS, Lee HJ, Lim I, Satoh J, Kim SU (2014) Human astrocytes: secretome profiles of cytokines and chemokines. PLoS One 9(4):e92325. CrossRefGoogle Scholar
  25. 25.
    Jakel S, Dimou L (2017) Glial cells and their function in the adult brain: a journey through the history of their ablation. Front Cell Neurosci 11:24. CrossRefGoogle Scholar
  26. 26.
    Yamakawa H, Cheng J, Penney J, Gao F, Rueda R, Wang J, Yamakawa S, Kritskiy O et al (2017) The transcription factor Sp3 cooperates with HDAC2 to regulate synaptic function and plasticity in neurons. Cell Rep 20(6):1319–1334. CrossRefGoogle Scholar
  27. 27.
    Ishimaru N, Tabuchi A, Hara D, Hayashi H, Sugimoto T, Yasuhara M, Shiota J, Tsuda M (2007) Regulation of neurotrophin-3 gene transcription by Sp3 and Sp4 in neurons. J Neurochem 100(2):520–531. CrossRefGoogle Scholar
  28. 28.
    Mao XR, Moerman-Herzog AM, Chen Y, Barger SW (2009) Unique aspects of transcriptional regulation in neurons—nuances in NFkappaB and Sp1-related factors. J Neuroinflammation 6:16. CrossRefGoogle Scholar
  29. 29.
    Lian H, Yang L, Cole A, Sun L, Chiang AC, Fowler SW, Shim DJ, Rodriguez-Rivera J et al (2015) NFkappaB-activated astroglial release of complement C3 compromises neuronal morphology and function associated with Alzheimer’s disease. Neuron 85(1):101–115. CrossRefGoogle Scholar
  30. 30.
    Shastri A, Bonifati DM, Kishore U (2013) Innate immunity and neuroinflammation. Mediators Inflamm 2013:342931. CrossRefGoogle Scholar
  31. 31.
    Okun E, Griffioen KJ, Lathia JD, Tang SC, Mattson MP, Arumugam TV (2009) Toll-like receptors in neurodegeneration. Brain Res Rev 59(2):278–292. CrossRefGoogle Scholar
  32. 32.
    Gesuete R, Kohama SG, Stenzel-Poore MP (2014) Toll-like receptors and ischemic brain injury. J Neuropathol Exp Neurol 73(5):378–386. CrossRefGoogle Scholar
  33. 33.
    Jacob A, Alexander JJ (2014) Complement and blood-brain barrier integrity. Mol Immunol 61(2):149–152. CrossRefGoogle Scholar
  34. 34.
    Rutkowski MJ, Sughrue ME, Kane AJ, Ahn BJ, Fang S, Parsa AT (2010) The complement cascade as a mediator of tissue growth and regeneration. Inflamm Res 59(11):897–905. CrossRefGoogle Scholar
  35. 35.
    Boulanger LM (2009) Immune proteins in brain development and synaptic plasticity. Neuron 64(1):93–109. CrossRefGoogle Scholar
  36. 36.
    Veerhuis R, Nielsen HM, Tenner AJ (2011) Complement in the brain. Mol Immunol 48(14):1592–1603. CrossRefGoogle Scholar
  37. 37.
    Fraser DA, Pisalyaput K, Tenner AJ (2010) C1q enhances microglial clearance of apoptotic neurons and neuronal blebs, and modulates subsequent inflammatory cytokine production. J Neurochem 112(3):733–743. CrossRefGoogle Scholar
  38. 38.
    Tokudome K, Okumura T, Shimizu S, Mashimo T, Takizawa A, Serikawa T, Terada R, Ishihara S et al (2016) Synaptic vesicle glycoprotein 2A (SV2A) regulates kindling epileptogenesis via GABAergic neurotransmission. Sci Rep 6:27420. CrossRefGoogle Scholar
  39. 39.
    Wood IC, Garriga M, Palmer CL, Pepitoni S, Buckley NJ (1999) Neuronal expression of the rat M1 muscarinic acetylcholine receptor gene is regulated by elements in the first exon. Biochem J 340(Pt 2):475–483CrossRefGoogle Scholar
  40. 40.
    Lou XY, Ma JZ, Payne TJ, Beuten J, Crew KM, Li MD (2006) Gene-based analysis suggests association of the nicotinic acetylcholine receptor beta1 subunit (CHRNB1) and M1 muscarinic acetylcholine receptor (CHRM1) with vulnerability for nicotine dependence. Hum Genet 120(3):381–389. CrossRefGoogle Scholar
  41. 41.
    Ma DQ, Whitehead PL, Menold MM, Martin ER, Ashley-Koch AE, Mei H, Ritchie MD, Delong GR et al (2005) Identification of significant association and gene-gene interaction of GABA receptor subunit genes in autism. Am J Hum Genet 77(3):377–388. CrossRefGoogle Scholar
  42. 42.
    Greene ND, Copp AJ (2014) Neural tube defects. Annu Rev Neurosci 37:221–242. CrossRefGoogle Scholar
  43. 43.
    Kalashnikova E, Lorca RA, Kaur I, Barisone GA, Li B, Ishimaru T, Trimmer JS, Mohapatra DP et al (2010) SynDIG1: an activity-regulated, AMPA- receptor-interacting transmembrane protein that regulates excitatory synapse development. Neuron 65(1):80–93. CrossRefGoogle Scholar
  44. 44.
    Maloyan A, Sanbe A, Osinska H, Westfall M, Robinson D, Imahashi K, Murphy E, Robbins J (2005) Mitochondrial dysfunction and apoptosis underlie the pathogenic process in alpha-B-crystallin desmin-related cardiomyopathy. Circulation 112(22):3451–3461. CrossRefGoogle Scholar
  45. 45.
    Garcia-Huerta P, Diaz-Hernandez M, Delicado EG, Pimentel-Santillana M, Miras-Portugal MT, Gomez-Villafuertes R (2012) The specificity protein factor Sp1 mediates transcriptional regulation of P2X7 receptors in the nervous system. J Biol Chem 287(53):44628–44644. CrossRefGoogle Scholar
  46. 46.
    Paonessa F, Latifi S, Scarongella H, Cesca F, Benfenati F (2013) Specificity protein 1 (Sp1)-dependent activation of the synapsin I gene (SYN1) is modulated by RE1-silencing transcription factor (REST) and 5′-cytosine-phosphoguanine (CpG) methylation. J Biol Chem 288(5):3227–3239. CrossRefGoogle Scholar
  47. 47.
    Boutillier S, Lannes B, Buee L, Delacourte A, Rouaux C, Mohr M, Bellocq JP, Sellal F et al (2007) Sp3 and sp4 transcription factor levels are increased in brains of patients with Alzheimer’s disease. Neurodegener Dis 4(6):413–423. CrossRefGoogle Scholar
  48. 48.
    Saia G, Lalonde J, Sun X, Ramos B, Gill G (2014) Phosphorylation of the transcription factor Sp4 is reduced by NMDA receptor signaling. J Neurochem 129(4):743–752. CrossRefGoogle Scholar
  49. 49.
    Ramos B, Gaudilliere B, Bonni A, Gill G (2007) Transcription factor Sp4 regulates dendritic patterning during cerebellar maturation. Proc Natl Acad Sci U S A 104(23):9882–9887. CrossRefGoogle Scholar
  50. 50.
    Aoyama T, Okamoto T, Fukiage K, Otsuka S, Furu M, Ito K, Jin Y, Ueda M et al (2010) Histone modifiers, YY1 and p300, regulate the expression of cartilage-specific gene, chondromodulin-I, in mesenchymal stem cells. J Biol Chem 285(39):29842–29850. CrossRefGoogle Scholar
  51. 51.
    Yao YL, Yang WM, Seto E (2001) Regulation of transcription factor YY1 by acetylation and deacetylation. Mol Cell Biol 21(17):5979–5991CrossRefGoogle Scholar
  52. 52.
    Han JW, Ahn SH, Kim YK, Bae GU, Yoon JW, Hong S, Lee HY, Lee YW et al (2001) Activation of p21(WAF1/Cip1) transcription through Sp1 sites by histone deacetylase inhibitor apicidin: involvement of protein kinase C. J Biol Chem 276(45):42084–42090. CrossRefGoogle Scholar
  53. 53.
    Billon N, Carlisi D, Datto MB, van Grunsven LA, Watt A, Wang XF, Rudkin BB (1999) Cooperation of Sp1 and p300 in the induction of the CDK inhibitor p21WAF1/CIP1 during NGF-mediated neuronal differentiation. Oncogene 18(18):2872–2882. CrossRefGoogle Scholar

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© Springer Science+Business Media, LLC, part of Springer Nature 2019

Authors and Affiliations

  1. 1.Department of Biotechnology and Bioindustry ScienceNational Cheng-Kung UniversityTainanTaiwan
  2. 2.Graduate Institute of Medical Sciences, College of MedicineTaipei Medical UniversityTaipeiTaiwan
  3. 3.The PhD Program for Neural Regenerative Medicine, College of Medical Science and TechnologyTaipei Medical UniversityTaipeiTaiwan
  4. 4.Center for Neurotrauma and NeuroregenerationTaipei Medical UniversityTaipeiTaiwan
  5. 5.Cellular Pathobiology Section, Integrative Neuroscience Research Branch, National Institute on Drug Abuse, National Institutes of HealthDepartment of Health and Human ServicesBaltimoreUSA

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