Clinical and Experimental Pediatrics

The Korean Pediatric Society (대한소아청소년과학회)
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NELL2 gene as regulator of cell cycle in neuron differentiation

신경세포 분화에서 세포주기 조절인자로서의 NELL2 유전자의 역할

  • Joung, Mi Rim (Department of Pediatrics, College of Medicine, Ulsan University Hospital) ;
  • Oh, Yeon Mi (Department of Pediatrics, College of Medicine, Ulsan University Hospital) ;
  • Park, Woo Saeng (Department of Pediatrics, College of Medicine, Ulsan University Hospital) ;
  • Park, Sang Kyu (Department of Pediatrics, College of Medicine, Ulsan University Hospital)
  • 정미림 (울산대학교 의과대학 소아과학교실) ;
  • 오연미 (울산대학교 의과대학 소아과학교실) ;
  • 박우생 (울산대학교 의과대학 소아과학교실) ;
  • 박상규 (울산대학교 의과대학 소아과학교실)
  • Received : 2006.07.21
  • Accepted : 2006.08.30
  • Published : 2006.10.15
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Abstract

Purpose : Because NELL2 expression is strictly restricted only in neurons in developing and post-differentiated neural tissues, it is thought to be involved in the neuronal differentiation during development and in the maintenance of neuronal physiology in the post-differentiated neurons. In this study, we examined whether NELL2 is involved in the regulation of cell cycle and apoptosis in the hippocampal neuroprogenitor HiB5 cells. Methods : Effects of NELL2 on the cultured HiB5 cell numbers, DNA fragmentation, and proteins involved in the regulation of the cell cycle were measured. Results : NELL2 induced a decrease in cell numbers and an increase in G1 phase arrest. Moreover, transfection of NELL2 resulted in an increase of DNA fragmentation that shows an evidence of apoptosis. Contents of proteins involved in the regulation of cell cycle were also changed by transfection of NELL2 expression vectors. Conclusion : This study suggests that NELL2 plays an important role in the regulation of cell cycle and apoptosis of neurons.

목 적 : 신경세포 분화에 있어 NELL2가 세포 주기와 세포자 멸사에 어떤 영향을 미치는지를 규명하고자 하였다. 방 법 : HiB5 세포에 NELL2를 전달감염시켜 배양하여 세포수를 측정하였다. 세포자멸사를 분석하기 위해 DNA 분절검사를 시행하였으며 PI염색으로 DNA양을 측정하였다. 세포주기의 조절에 관여하는 단백질에 대한 NELL2의 효과를 측정하기 위하여 Western blot과 면역염색을 시행하였다. 결 과 : NELL2를 전달감염시킨 군에서 세포수가 의미가 있게 적었고 DNA 분절검사에서 세포자멸사를 확인하였으며 $G_1$ 정지가 증가하였다. Western blot과 면역염색결과 Rb단백, p53, E2F1(KH-95)이 NELL2를 전달감염시킨 군에서 증가하고 cyclin D가 NELL2를 전달감염시킨 군에서 감소하였다. 결 론 : HiB5 세포에서 NELL2에 의하여 일정 수준에서의 세포자멸사가 동반되고 세포 주기에 있어 $G_1$기의 정지가 일어나며 세포주기를 조절하는 단백질의 변화가 발생함을 확인하였다. 따라서 NELL2가 뇌에서 신경세포 분화에 중요한 역할을 할 걸로 생각된다.

Keywords

References

  1. Tobet SA, Basham ME, Baum MJ. Estrogen receptor immunoreactive neurons in the fetalferret forebrain. Brain Res Dev Brain Res 1993;72:167-80 https://doi.org/10.1016/0165-3806(93)90182-A
  2. Naftolin F, Garcia-Segura LM, Keefe D, LeranthC, Maclusky NJ, Brawer JR. Estrogen effects on the synaptology and neural membranes of the rat hypothalamic arcuate nucleus. Biol Reprod 1990;42:21-8 https://doi.org/10.1095/biolreprod42.1.21
  3. Choi EJ, Ha CM, Choi J, Kang SS, Park SK, Choi WS, et al. Low-density cDNA array-coupled to PCR differential display identifies new estrogen-responsive genes during the postnatal differentiation of the rat hypothalamus. Mol Brain Res 2001;97:115-28 https://doi.org/10.1016/S0169-328X(01)00302-3
  4. Matsuhashi S, Noji S, Koyama E, Myokai F, Ohuchi H, Taniguchi S, et al. New gene, nel, encoding a M(r) 93K protein with EGF-like repeats is strongly expressed in neural tissues of early stage chick embryos. Dev Dyn 1995; 203:212-22 https://doi.org/10.1002/aja.1002030209
  5. Watanabe TK, Katagiri T, Suzuki M, Shimizu F, Fujiwara T, Kanemoto N, et al. Cloning and characterization of two novel human cDNAs(NELL1 and NELL2) encoding proteins with six EGF-like repeats. Genomics 1996;38:273-6 https://doi.org/10.1006/geno.1996.0628
  6. Oyasu M, Kuroda S, Nakashita M, Fujimiya M, Kikkawa U, Saito N. Immunocytochemical localization of a neuronspecificthrombospondin- 1-like protein, NELL2 : light and electron microscopic studies in the rat brain. Mol Brain Res 2000;76:151-60 https://doi.org/10.1016/S0169-328X(99)00342-3
  7. Kim H, Ha CM, Choi J, Choi E, Jeon J, Kim C, et al. Ontogeny and the possible function of a novel epidermal growth factor-like repeat domain-containing protein, NELL2, in the rat brain. J Neurochem 2002;83:1389-400 https://doi.org/10.1046/j.1471-4159.2002.01245.x
  8. Zacksenhaus E, Bremner R, Phillips RA, Gallie BL. A bipartite nuclear localization signal in the retinoblastoma gene product and its importancefor biological activity. Mol Cell Biol 1993;13:4588-99 https://doi.org/10.1128/MCB.13.8.4588
  9. Yee AS, Shih HH, Tevosian SG. Newperspective on retinoblastoma family functions in differentiation. Front Biosci 1998;3:D532-D547 https://doi.org/10.2741/A301
  10. Weinberg RA. The retinoblastoma protein and cell cycle control. Cell 1995;91:2642-54
  11. Sherr CJ. Cancer cell cycles. Science 1996;274:1672-7 https://doi.org/10.1126/science.274.5293.1672
  12. Renfranz PJ, Cunningham MG, McKay RD. Region-specific differentiation of the hippocampal stem cell line HiB5 upon implantation into the developing mammalianbrain. Cell 1991; 66:713-29 https://doi.org/10.1016/0092-8674(91)90116-G
  13. Kwon YK. Expression of brain-derivedneurotrophic factor mRNA stimulated by basic fibroblast growth factor and platelet-derived growth factor in rat hippocampal cell line. Mol Cells 1997;7:320-325
  14. Chung JJ, Cho S, Kwon WK, Kim D, Kim K. Activation of retinoic acid receptor γ inducesproliferation of immortalized hippocampal progenitor cells. Brain Res Mol Brain Res 2000;83:52-62 https://doi.org/10.1016/S0169-328X(00)00196-0
  15. Morris L, Allen KE, La Thangue NB. Regulation of E2F transcription by cyclin E-Cdk2 kinase mediated through p300/CBP co-activators. Nat Cell Biol 2000;2:232-9 https://doi.org/10.1038/35008660
  16. Kusek JC, Greene RM, Nugent P, Pisano MM. Expression of the E2F family of transcription factors during murine development. Int J Dev Biol 2000;44:267-77
  17. Kusek JC, Greene RM, Pisano MM. Expression of the E2F and retinoblastoma families of proteins during neural differentiation. Brain Res Bull 2001;54:187-98 https://doi.org/10.1016/S0361-9230(00)00447-0
  18. Dowdy SF, Hinds PW, Louis K, Reed SI, Arnold A, Weinberg RA. Physical interaction of the retinoblastoma protein with human cyclins. Cell 1993;73:499-511 https://doi.org/10.1016/0092-8674(93)90137-F