DOI QR코드

DOI QR Code

Nuclear localization of Obox4 is dependent on its homeobox domain

  • Park, Geon Tae (Department of Biomedical Science, College of Life Science, CHA University) ;
  • Lee, Kyung-Ah (Department of Biomedical Science, College of Life Science, CHA University)
  • Received : 2013.01.23
  • Accepted : 2013.02.20
  • Published : 2013.03.31

Abstract

Objective: Oocyte-specific homeobox 4 (Obox4) is preferentially expressed in oocytes and plays an important role in the completion of meiosis of oocytes. However, the Obox4 expression pattern has not been reported yet. In this study, we investigated the subcellular localization of Obox4 using a green fluorescent protein (GFP) fusion expression system. Methods: Three regions of Obox4 were divided and fused to the GFP expression vector. The partly deleted homeodomain (HD) regions of Obox4 were also fused to the GFP expression vector. The recombinant vectors were transfected into HEK-293T cells plated onto coated glass coverslips. The transfected cells were stained with 4',6-diamidino-2-phenylindol and photographed using a fluorescence microscope. Results: Mutants containing the HD region as well as full-length Obox4 were clearly localized to the nucleus. In contrast, the other mutants of either the N-terminal or C-terminal region without HD had impaired nuclear localization. We also found that the N-terminal and C-terminal of the Obox HD contributed to nuclear localization and the entire HD was necessary for nuclear localization of Obox4. Conclusion: Based on the results of the present study, we demonstrated that the intact HD region of Obox4 is responsible for the nuclear localization of Obox4 protein in cells.

Keywords

References

  1. Rajkovic A, Yan C, Yan W, Klysik M, Matzuk MM. Obox, a family of homeobox genes preferentially expressed in germ cells. Genomics 2002;79:711-7. https://doi.org/10.1006/geno.2002.6759
  2. Cheng WC, Hsieh-Li HM, Yeh YJ, Li H. Mice lacking the Obox6 homeobox gene undergo normal early embryonic development and are fertile. Dev Dyn 2007;236:2636-42. https://doi.org/10.1002/dvdy.21261
  3. Lee HS, Lee KA. Characterization and functional analysis of Obox4 during oocyte maturation by RNA interference. Korean J Reprod Med 2007;34:293-303.
  4. Del Bene F, Wittbrodt J. Cell cycle control by homeobox genes in development and disease. Semin Cell Dev Biol 2005;16:449-60. https://doi.org/10.1016/j.semcdb.2005.02.001
  5. Garcia-Fernandez J. The genesis and evolution of homeobox gene clusters. Nat Rev Genet 2005;6:881-92. https://doi.org/10.1038/nrg1723
  6. Lee HS, Kim EY, Kim KH, Moon J, Park KS, Kim KS, et al. Obox4 critically regulates cAMP-dependent meiotic arrest and MI-MII transition in oocytes. FASEB J 2010;24:2314-24. https://doi.org/10.1096/fj.09-147314
  7. Barnes FL, Sirard MA. Oocyte maturation. Semin Reprod Med 2000;18:123-31. https://doi.org/10.1055/s-2000-12551
  8. Kim HM, Ahn HJ, Lee HS, Lee KA, Lee SM, Kim HH, et al. Obox4 regulates the expression of histone family genes and promotes differentiation of mouse embryonic stem cells. FEBS Lett 2010; 584:605-11. https://doi.org/10.1016/j.febslet.2009.12.005
  9. Do HJ, Lim HY, Kim JH, Song H, Chung HM. An intact homeobox domain is required for complete nuclear localization of human Nanog. Biochem Biophys Res Commun 2007;353:770-5. https://doi.org/10.1016/j.bbrc.2006.12.100
  10. Hessabi B, Schmidt I, Walther R. The homeodomain of Nkx2.2 carries two cooperatively acting nuclear localization signals. Biochem Biophys Res Commun 2000;270:695-700. https://doi.org/10.1006/bbrc.2000.2491
  11. Scott MP, Tamkun JW, Hartzell GW 3rd. The structure and function of the homeodomain. Biochim Biophys Acta 1989;989:25-48.
  12. Gorlich D, Kutay U. Transport between the cell nucleus and the cytoplasm. Annu Rev Cell Dev Biol 1999;15:607-60. https://doi.org/10.1146/annurev.cellbio.15.1.607
  13. Schwoebel ED, Moore MS. The control of gene expression by regulated nuclear transport. Essays Biochem 2000;36:105-13.
  14. Ye W, Lin W, Tartakoff AM, Tao T. Karyopherins in nuclear transport of homeodomain proteins during development. Biochim Biophys Acta 2011;1813:1654-62. https://doi.org/10.1016/j.bbamcr.2011.01.013
  15. Ploski JE, Topisirovic I, Park KW, Borden KL, Radu A. A mechanism of nucleocytoplasmic trafficking for the homeodomain protein PRH. Mol Cell Biochem 2009;332:173-81. https://doi.org/10.1007/s11010-009-0188-0
  16. Park SW, Do HJ, Huh SH, Sung B, Uhm SJ, Song H, et al. Identification of a putative nuclear export signal motif in human NANOG homeobox domain. Biochem Biophys Res Commun 2012;421: 484-9. https://doi.org/10.1016/j.bbrc.2012.04.025
  17. Ghaffari M, Zeng X, Whitsett JA, Yan C. Nuclear localization domain of thyroid transcription factor-1 in respiratory epithelial cells. Biochem J 1997;328(Pt 3):757-61. https://doi.org/10.1042/bj3280757
  18. Sock E, Enderich J, Rosenfeld MG, Wegner M. Identification of the nuclear localization signal of the POU domain protein Tst-1/ Oct6. J Biol Chem 1996;271:17512-8. https://doi.org/10.1074/jbc.271.29.17512
  19. Hessabi B, Ziegler P, Schmidt I, Hessabi C, Walther R. The nuclear localization signal (NLS) of PDX-1 is part of the homeodomain and represents a novel type of NLS. Eur J Biochem 1999;263:170-7. https://doi.org/10.1046/j.1432-1327.1999.00481.x

Cited by

  1. Associations among Sebox and Other MEGs and Its Effects on Early Embryogenesis vol.10, pp.2, 2013, https://doi.org/10.1371/journal.pone.0115050