, Volume 21, Issue 6, pp 737–748 | Cite as

Actin depolymerization mediated loss of SNTA1 phosphorylation and Rac1 activity has implications on ROS production, cell migration and apoptosis

  • Sehar Saleem Bhat
  • Arif Ali Parray
  • Umar Mushtaq
  • Khalid Majid Fazili
  • Firdous Ahmad Khanday


Alpha-1-syntrophin (SNTA1) and Rac1 are part of a signaling pathway via the dystrophin glycoprotein complex (DGC). Both SNTA1 and Rac1 proteins are over-expressed in various carcinomas. It is through the DGC signaling pathway that SNTA1 has been shown to act as a link between the extra cellular matrix, the internal cell signaling apparatus and the actin cytoskeleton. SNTA1 is involved in the modulation of the actin cytoskeleton and actin reorganization. Rac1 also controls actin cytoskeletal organization in the cell. In this study, we present the interplay between f-actin, SNTA1 and Rac1. We analyzed the effect of actin depolymerization on SNTA1 tyrosine phosphorylation and Rac1 activity using actin depolymerizing drugs, cytochalasin D and latrunculin A. Our results indicate a marked decrease in the tyrosine phosphorylation of SNTA1 upon actin depolymerization. Results suggest that actin depolymerization mediated loss of SNTA1 phosphorylation leads to loss of interaction between SNTA1 and Rac1, with a concomitant loss of Rac1 activation. The loss of SNTA1tyrosine phosphorylation and Rac1 activity by actin depolymerization results in increased apoptosis, decreased cell migration and decreased reactive oxygen species (ROS) levels in breast carcinoma cells. Collectively, our results present a possible role of f-actin in the SNTA1-Rac1 signaling pathway and implications of actin depolymerization on cell migration, ROS production and apoptosis.


Breast cancer Alpha-1-syntrophin Actin Rac1 ROS Apoptosis 



This work was supported by Deanship of Research, King Fahd University of Petroleum and Minerals, through the start-up grant scheme to Dr. Firdous A. Khanday, No. SR141006. It was partly financed by a grant to SSB by the University Grants Commission of India, No F. 17-82/2008(SA-I) to SSB. We are grateful to Dr. KS Siddiqui and A Ismail, for carrying out the scientific content and language editing of the manuscript.

Compliance with ethical standards

Conflict of interest

The authors declare no conflicts of interest.


  1. 1.
    Sheng M, Sala C (2001) PDZ domains and the organization of supramolecular complexes. Annu Rev Neurosci 24:1–29CrossRefPubMedGoogle Scholar
  2. 2.
    Adams ME, Dwyer TM, Dowler LL, White RA, Froehner SC (1995) Mouse alpha 1- and beta 2-syntrophin gene structure, chromosome localization, and homology with a discs large domain. J Biol Chem 270:25859–25865CrossRefPubMedGoogle Scholar
  3. 3.
    Ahn AH, Yoshida M, Anderson MS et al (1994) Cloning of human basic A1, a distinct 59-kDa dystrophin-associated protein encoded on chromosome 8q23-24. Proc Natl Acad Sci USA 91:4446–4450CrossRefPubMedPubMedCentralGoogle Scholar
  4. 4.
    Adams ME, Butler MH, Dwyer TM, Peters MF, Murnane AA, Froehner SC (1993) Two forms of mouse syntrophin, a 58 kd dystrophin-associated protein, differ in primary structure and tissue distribution. Neuron 11:531–540CrossRefPubMedGoogle Scholar
  5. 5.
    Yang B, Ibraghimov-Beskrovnaya O, Moomaw CR, Slaughter CA, Campbell KP (1994) Heterogeneity of the 59-kDa dystrophin-associated protein revealed by cDNA cloning and expression. J Biol Chem 269:6040–6044PubMedGoogle Scholar
  6. 6.
    Ahn AH, Kunkel LM (1993) The structural and functional diversity of dystrophin. Nat Genet 3:283–291CrossRefPubMedGoogle Scholar
  7. 7.
    Piluso G, Mirabella M, Ricci E et al (2000) Gamma1- and gamma2-syntrophins, two novel dystrophin-binding proteins localized in neuronal cells. J Biol Chem 275:15851–15860CrossRefPubMedGoogle Scholar
  8. 8.
    Ahn AH, Kunkel LM (1995) Syntrophin binds to an alternatively spliced exon of dystrophin. J Cell Biol 128:363–371CrossRefPubMedGoogle Scholar
  9. 9.
    Kramarcy NR, Vidal A, Froehner SC, Sealock R (1994) Association of utrophin and multiple dystrophin short forms with the mammalian M(r) 58,000 dystrophin-associated protein (syntrophin). J Biol Chem 269:2870–2876PubMedGoogle Scholar
  10. 10.
    Hoffman EP, Brown RH Jr, Kunkel LM (1987) Dystrophin: the protein product of the Duchenne muscular dystrophy locus. Cell 51:919–928CrossRefPubMedGoogle Scholar
  11. 11.
    Campbell KP, Kahl SD (1989) Association of dystrophin and an integral membrane glycoprotein. Nature 338:259–262CrossRefPubMedGoogle Scholar
  12. 12.
    Butler MH, Douville K, Murnane AA et al (1992) Association of the Mr 58,000 postsynaptic protein of electric tissue with Torpedo dystrophin and the Mr 87,000 postsynaptic protein. J Biol Chem 267:6213–6218PubMedGoogle Scholar
  13. 13.
    Ahn AH, Freener CA, Gussoni E, Yoshida M, Ozawa E, Kunkel LM (1996) The three human syntrophin genes are expressed in diverse tissues, have distinct chromosomal locations, and each bind to dystrophin and its relatives. J Biol Chem 271:2724–2730CrossRefPubMedGoogle Scholar
  14. 14.
    Bhat HF, Baba RA, Bashir M et al (2011) Alpha-1-syntrophin protein is differentially expressed in human cancers. Biomarkers 16:31–36CrossRefPubMedGoogle Scholar
  15. 15.
    Adams ME, Kramarcy N, Krall SP et al (2000) Absence of alpha-syntrophin leads to structurally aberrant neuromuscular synapses deficient in utrophin. J Cell Biol 150:1385–1398CrossRefPubMedPubMedCentralGoogle Scholar
  16. 16.
    Petrof BJ, Shrager JB, Stedman HH, Kelly AM, Sweeney HL (1993) Dystrophin protects the sarcolemma from stresses developed during muscle contraction. Proc Natl Acad Sci USA 90:3710–3714CrossRefPubMedPubMedCentralGoogle Scholar
  17. 17.
    Abramovici H, Hogan AB, Obagi C, Topham MK, Gee SH (2003) Diacylglycerol kinase-zeta localization in skeletal muscle is regulated by phosphorylation and interaction with syntrophins. Mol Biol Cell 14:4499–4511CrossRefPubMedPubMedCentralGoogle Scholar
  18. 18.
    Hogan A, Yakubchyk Y, Chabot J et al (2004) The phosphoinositol 3,4-bisphosphate-binding protein TAPP1 interacts with syntrophins and regulates actin cytoskeletal organization. J Biol Chem 279:53717–53724CrossRefPubMedGoogle Scholar
  19. 19.
    Cantley LC (2002) The phosphoinositide 3-kinase pathway. Science 296:1655–1657CrossRefPubMedGoogle Scholar
  20. 20.
    Madhavan R, Massom LR, Jarrett HW (1992) Calmodulin specifically binds three proteins of the dystrophin-glycoprotein complex. Biochem Biophys Res Commun 185:753–759CrossRefPubMedGoogle Scholar
  21. 21.
    Iwata Y, Sampaolesi M, Shigekawa M, Wakabayashi S (2004) Syntrophin is an actin-binding protein the cellular localization of which is regulated through cytoskeletal reorganization in skeletal muscle cells. Eur J Cell Biol 83:555–565CrossRefPubMedGoogle Scholar
  22. 22.
    Bhat HF, Adams ME, Khanday FA (2013) Syntrophin proteins as Santa Claus: role(s) in cell signal transduction. Cell Mol Life Sci 70:2533–2554CrossRefPubMedGoogle Scholar
  23. 23.
    Kimber WA, Trinkle-Mulcahy L, Cheung PC et al (2002) Evidence that the tandem-pleckstrin-homology-domain-containing protein TAPP1 interacts with Ptd(3,4)P2 and the multi-PDZ-domain-containing protein MUPP1 in vivo. Biochem J 361:525–536CrossRefPubMedPubMedCentralGoogle Scholar
  24. 24.
    Dowler S, Currie RA, Downes CP, Alessi DR (1999) DAPP1: a dual adaptor for phosphotyrosine and 3-phosphoinositides. Biochem J 342(Pt 1):7–12CrossRefPubMedPubMedCentralGoogle Scholar
  25. 25.
    Dowler S, Currie RA, Campbell DG et al (2000) Identification of pleckstrin-homology-domain-containing proteins with novel phosphoinositide-binding specificities. Biochem J 351:19–31CrossRefPubMedPubMedCentralGoogle Scholar
  26. 26.
    Marshall AJ, Krahn AK, Ma K, Duronio V, Hou S (2002) TAPP1 and TAPP2 are targets of phosphatidylinositol 3-kinase signaling in B cells: sustained plasma membrane recruitment triggered by the B-cell antigen receptor. Mol Cell Biol 22:5479–5491CrossRefPubMedPubMedCentralGoogle Scholar
  27. 27.
    Hasegawa M, Cuenda A, Spillantini MG et al (1999) Stress-activated protein kinase-3 interacts with the PDZ domain of alpha1-syntrophin. A mechanism for specific substrate recognition. J Biol Chem 274:12626–12631CrossRefPubMedGoogle Scholar
  28. 28.
    Oak SA, Russo K, Petrucci TC, Jarrett HW (2001) Mouse alpha1-syntrophin binding to Grb2: further evidence of a role for syntrophin in cell signaling. Biochemistry 40:11270–11278CrossRefPubMedGoogle Scholar
  29. 29.
    Oak SA, Zhou YW, Jarrett HW (2003) Skeletal muscle signaling pathway through the dystrophin glycoprotein complex and Rac1. J Biol Chem 278:39287–39295CrossRefPubMedGoogle Scholar
  30. 30.
    Bhat HF, Baba RA, Adams ME, Khanday FA (2014) Role of SNTA1 in Rac1 activation, modulation of ROS generation, and migratory potential of human breast cancer cells. Br J Cancer 110:706–714CrossRefPubMedPubMedCentralGoogle Scholar
  31. 31.
    Ridley AJ, Schwartz MA, Burridge K et al (2003) Cell migration: integrating signals from front to back. Science 302:1704–1709CrossRefPubMedGoogle Scholar
  32. 32.
    Nobes CD, Hall A (1999) Rho GTPases control polarity, protrusion, and adhesion during cell movement. J Cell Biol 144:1235–1244CrossRefPubMedPubMedCentralGoogle Scholar
  33. 33.
    Kraynov VS, Chamberlain C, Bokoch GM, Schwartz MA, Slabaugh S, Hahn KM (2000) Localized Rac activation dynamics visualized in living cells. Science 290:333–337CrossRefPubMedGoogle Scholar
  34. 34.
    Ridley AJ (2001) Rho GTPases and cell migration. J Cell Sci 114:2713–2722PubMedGoogle Scholar
  35. 35.
    Benitah SA, Valeron PF, van Aelst L, Marshall CJ, Lacal JC (2004) Rho GTPases in human cancer: an unresolved link to upstream and downstream transcriptional regulation. Biochim Biophys Acta 1705:121–132PubMedGoogle Scholar
  36. 36.
    Choi UJ, Jee BK, Lim Y, Lee KH (2009) KAI1/CD82 decreases Rac1 expression and cell proliferation through PI3K/Akt/mTOR pathway in H1299 lung carcinoma cells. Cell Biochem Funct 27:40–47CrossRefPubMedGoogle Scholar
  37. 37.
    Bishop AL, Hall A (2000) Rho GTPases and their effector proteins. Biochem J 348(Pt 2):241–255CrossRefPubMedPubMedCentralGoogle Scholar
  38. 38.
    Whaley-Connell AT, Morris EM, Rehmer N et al (2007) Albumin activation of NAD(P)H oxidase activity is mediated via Rac1 in proximal tubule cells. Am J Nephrol 27:15–23CrossRefPubMedGoogle Scholar
  39. 39.
    Ellenbroek SI, Collard JG (2007) Rho GTPases: functions and association with cancer. Clin Exp Metastasis 24:657–672CrossRefPubMedGoogle Scholar
  40. 40.
    Vega FM, Ridley AJ (2008) Rho GTPases in cancer cell biology. FEBS Lett 582:2093–2101CrossRefPubMedGoogle Scholar
  41. 41.
    Fritz G, Just I, Kaina B (1999) Rho GTPases are over-expressed in human tumors. Int J Cancer 81:682–687CrossRefPubMedGoogle Scholar
  42. 42.
    Schnelzer A, Prechtel D, Knaus U et al (2000) Rac1 in human breast cancer: overexpression, mutation analysis, and characterization of a new isoform, Rac1b. Oncogene 19:3013–3020CrossRefPubMedGoogle Scholar
  43. 43.
    Wang J, Rao Q, Wang M et al (2009) Overexpression of Rac1 in leukemia patients and its role in leukemia cell migration and growth. Biochem Biophy Res Commun 386:769–774CrossRefGoogle Scholar
  44. 44.
    Wertheimer E, Gutierrez-Uzquiza A, Rosemblit C, Lopez-Haber C, Sosa MS, Kazanietz MG (2012) Rac signaling in breast cancer: a tale of GEFs and GAPs. Cell Signal 24:353–362CrossRefPubMedPubMedCentralGoogle Scholar
  45. 45.
    Schliwa M (1982) Action of cytochalasin D on cytoskeletal networks. J Cell Biol 92:79–91CrossRefPubMedGoogle Scholar
  46. 46.
    Brown SS, Spudich JA (1981) Mechanism of action of cytochalasin: evidence that it binds to actin filament ends. J Cell Biol 88:487–491CrossRefPubMedGoogle Scholar
  47. 47.
    Casella JF, Flanagan MD, Lin S (1981) Cytochalasin D inhibits actin polymerization and induces depolymerization of actin filaments formed during platelet shape change. Nature 293:302–305CrossRefPubMedGoogle Scholar
  48. 48.
    Pelham RJ Jr, Wang Y (1999) High resolution detection of mechanical forces exerted by locomoting fibroblasts on the substrate. Mol Biol Cell 10:935–945CrossRefPubMedPubMedCentralGoogle Scholar
  49. 49.
    Coue M, Brenner SL, Spector I, Korn ED (1987) Inhibition of actin polymerization by latrunculin A. FEBS Lett 213:316–318CrossRefPubMedGoogle Scholar
  50. 50.
    Konishi H, Kikuchi S, Ochiai T et al (2009) Latrunculin a has a strong anticancer effect in a peritoneal dissemination model of human gastric cancer in mice. Anticancer Res 29:2091–2097PubMedGoogle Scholar
  51. 51.
    Wakatsuki T, Schwab B, Thompson NC, Elson EL (2001) Effects of cytochalasin D and latrunculin B on mechanical properties of cells. J Cell Sci 114:1025–1036PubMedGoogle Scholar

Copyright information

© Springer Science+Business Media New York 2016

Authors and Affiliations

  • Sehar Saleem Bhat
    • 1
  • Arif Ali Parray
    • 1
  • Umar Mushtaq
    • 1
  • Khalid Majid Fazili
    • 1
  • Firdous Ahmad Khanday
    • 1
    • 2
  1. 1.Department of BiotechnologyUniversity of KashmirSrinagarIndia
  2. 2.Department of Life SciencesKing Fahd University of Petroleum and MineralsDhahranKingdom of Saudi Arabia

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