人类心脏发育候选基因FBL5的表达与功能研究
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摘要
心血管疾病是危害人类健康的严重疾病。它是造成死亡的主要原因之一。为攻克这一顽症,首先必须从分子水平上系统地研究控制心脏发育的基因及其相互调控关系。
本实验室在研究基因FoxP4时,通过酵母双杂交筛选获得了一个相互作用蛋白FBL5, FBL5属于F-box家族蛋白成员,这类蛋白质在泛素-蛋白酶体途径中起非常重要的作用,近来的研究资料表明泛素-蛋白酶体途径与心血管疾病有关。因此对FBL5基因的深入研究对于探讨心血管疾病的基因调控机制,以及心血管疾病的诊断、治疗具有重大的理论和实践意义。
为了研究FBL5的表达与功能,从人类脑cDNA文库中克隆了FBL5基因的开放阅读框全长。亚细胞定位分析表明,FBL5定位于细胞质。
荧光素酶报告基因分析表明,FBL5是个转录抑制子,并抑制SRF的调控活性。利用原核表达系统表达并获得GST-FBL5融合蛋白,免疫新西兰大白兔获得兔抗人FBL5蛋白的多克隆抗体。
利用生物信息学从NCBI上搜索到FBL5的斑马鱼同源基因,克隆了其中特异性较强的一段,制备带有地高辛标记的探针,进行斑马鱼各个时期的整体胚胎原位杂交。实验结果显示FBL5在斑马鱼1细胞期到48小时的胚胎中均有表达,且在大脑、心脏和骨骼中表达强烈。
利用morpholino oligo显微注射法,沉默FBL5在斑马鱼中的表达,结果表明在1-2细胞期注射,并培养到48小时,得到的胚胎畸形率最高,畸形特征表现为胚胎体轴弯曲,心脏发育畸形,心率减慢。
将FBL5-MO与FoxP4-MO分别注射到斑马鱼中,用FBL5的探针进行整体原位杂交实验,发现注射了FBL5-MO与FoxP4-MO的胚胎,FBL5表达量都下降。初步研究表明,FBL5在心脏发育过程中起调控作用,与FoxP4共同调控心脏的发育过程。
Cardiovascular diseases have become one of the most serious diseases that threaten human beings. It is a critical prerequisite to understand the normal progress of cardiovascular development and the mechanisms underlying the causes of this kind of diseases.
In previous work, we performed yeast two-hybrid screen and obtained FBL5 as a binding partner of FoxP4. FBL5 belongs to F-box protein family.This protein family constitute one of the four subunits of ubiquitin protein ligase complex called SCFs (SKP-cullin-F-box), which governs ubiquitin-proteasome pathway. Recent study showed that ubiquitin-proteasome pathway is related to cardiovascular diseases.
In order to promote our understanding the expression and function of FBL5, the full-length cDNA was isolated from a human brain cDNA library. Using immunofluorescence staining, FBL5 alone distributes in the cytoplasm and still distributes in the cytoplasm when FoxP4 was coexpressed in COS-7 cells.Luciferase assay showed that FBL5 is a transcriptional inhibitor,and can inhibit the regulation activity of SRF
Using bioinformatics we found the zebrafish homologous gene of FBL5. A fragment of FBL5 was amplified by the PCR and inserted into pGEM-T. Antisense digoxigenin-labeled riboprobe was prepared using this construct. Whole-mount in situ hybridization revealed FBL5 expression in the heart, the brain and the bones. Injection of zebrafish embryos with a morpholino directed against FBL5 resulted in embryos with a notochord and an unlooped heart tube. The in situ hybridization assay used embryos injected with FBL5-MO or FoxP4-MO at 48hpf, showed that FBL5 expression decreased in FBL5-MO and FoxP4-MO samples. Conclusion, FBL5 have important function in the zebrafish heart development.
本实验室在研究基因FoxP4时,通过酵母双杂交筛选获得了一个相互作用蛋白FBL5, FBL5属于F-box家族蛋白成员,这类蛋白质在泛素-蛋白酶体途径中起非常重要的作用,近来的研究资料表明泛素-蛋白酶体途径与心血管疾病有关。因此对FBL5基因的深入研究对于探讨心血管疾病的基因调控机制,以及心血管疾病的诊断、治疗具有重大的理论和实践意义。
为了研究FBL5的表达与功能,从人类脑cDNA文库中克隆了FBL5基因的开放阅读框全长。亚细胞定位分析表明,FBL5定位于细胞质。
荧光素酶报告基因分析表明,FBL5是个转录抑制子,并抑制SRF的调控活性。利用原核表达系统表达并获得GST-FBL5融合蛋白,免疫新西兰大白兔获得兔抗人FBL5蛋白的多克隆抗体。
利用生物信息学从NCBI上搜索到FBL5的斑马鱼同源基因,克隆了其中特异性较强的一段,制备带有地高辛标记的探针,进行斑马鱼各个时期的整体胚胎原位杂交。实验结果显示FBL5在斑马鱼1细胞期到48小时的胚胎中均有表达,且在大脑、心脏和骨骼中表达强烈。
利用morpholino oligo显微注射法,沉默FBL5在斑马鱼中的表达,结果表明在1-2细胞期注射,并培养到48小时,得到的胚胎畸形率最高,畸形特征表现为胚胎体轴弯曲,心脏发育畸形,心率减慢。
将FBL5-MO与FoxP4-MO分别注射到斑马鱼中,用FBL5的探针进行整体原位杂交实验,发现注射了FBL5-MO与FoxP4-MO的胚胎,FBL5表达量都下降。初步研究表明,FBL5在心脏发育过程中起调控作用,与FoxP4共同调控心脏的发育过程。
Cardiovascular diseases have become one of the most serious diseases that threaten human beings. It is a critical prerequisite to understand the normal progress of cardiovascular development and the mechanisms underlying the causes of this kind of diseases.
In previous work, we performed yeast two-hybrid screen and obtained FBL5 as a binding partner of FoxP4. FBL5 belongs to F-box protein family.This protein family constitute one of the four subunits of ubiquitin protein ligase complex called SCFs (SKP-cullin-F-box), which governs ubiquitin-proteasome pathway. Recent study showed that ubiquitin-proteasome pathway is related to cardiovascular diseases.
In order to promote our understanding the expression and function of FBL5, the full-length cDNA was isolated from a human brain cDNA library. Using immunofluorescence staining, FBL5 alone distributes in the cytoplasm and still distributes in the cytoplasm when FoxP4 was coexpressed in COS-7 cells.Luciferase assay showed that FBL5 is a transcriptional inhibitor,and can inhibit the regulation activity of SRF
Using bioinformatics we found the zebrafish homologous gene of FBL5. A fragment of FBL5 was amplified by the PCR and inserted into pGEM-T. Antisense digoxigenin-labeled riboprobe was prepared using this construct. Whole-mount in situ hybridization revealed FBL5 expression in the heart, the brain and the bones. Injection of zebrafish embryos with a morpholino directed against FBL5 resulted in embryos with a notochord and an unlooped heart tube. The in situ hybridization assay used embryos injected with FBL5-MO or FoxP4-MO at 48hpf, showed that FBL5 expression decreased in FBL5-MO and FoxP4-MO samples. Conclusion, FBL5 have important function in the zebrafish heart development.
引文
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[3] Zheng N, Schulman BA, Song L, et al. Structure of the Cull- Rbxl- Skpl-F boxSkp2 SCF ubiquitin ligase complex. Nature, 2002, 416: 703-709.
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[8] Welchman RL, Gordon C, Mayer RJ. Ubiquitin and ubiquitin like proteins as multifunctional signals. Nat Rev Mol Cell Biol, 2005, 6: 599-609.
[9] Pickart CM, EddinsMJ. Ubiquitin: structures, functions, mechanisms. Biochem Biophys Acta, 2004,1695: 55-72.
[10] Zavrski I, Jakob C, Schmid P, et al. Proteasome: an emerging target for cancer therapy. AnticancerDrugs, 2005, 16: 475-481.
[11] Ciechanover A , Orian A , Schwartz AL. The ubiquitin-mediated proteolytic pathway:mode of action and clinical implications. J Cell Biochem , 2000 , 34 (Suppl): 40251.
[12] Yamamoto Y, Gaynor RB. Therapeutic potential of inhibition of the NF-kappaB pathway in the treatment of inflammation and cancer . J Clin Invest, 2001 , 107 (2): 1352142.
[13] Herrmann J , Gulati R , Napoli C , et al . Oxidative stress-related increase in ubiquitination in early coronary at herosclerosis. FASEB J , 2003 , 17 (12): 173021732.
[14] Friguet B , Bulteau AL , Conconi M , et al . Redox cont rol of the 20S proteasome. Met hods Enzymol, 2002 , 353 : 2532262.
[15] Bulteau AL , Lundberg KC , Humphries KM , et al . Oxidative modification and inactivation of the proteasome during coronary occlusion/ reperfusion. J Biol Chem , 2001 , 276 ( 32 ) : 30057230063.
[16] Vieira O , Escargueil2Blanc I , J u rgens G, et al . Oxidized LDLs alter the activity of the ubiquitin-proteasome pathway: potential role in oxidized LDL-induced apoptosis. FASEB J , 2000 , 14(3) : 5322542.
[17] Hansson GK. Immune mechanisms in atherosclerosis , Arterio-scler Thromb Vasc Biol, 2001 , 21 (12): 187621890.
[18] Libby P. Changing concept s of at herogenesis. J Intern Med ,2000 , 247 (3): 3492358.
[19] Herrmann J , Edwards WD, Schwartz RS , et al. Increasedubiquitin immunoreactivity in unstable at herosclerotic plaques associated wit h acute coronary syndromes. J Am coll Cardiol ,2002 , 40 : 191921927.
[20] Liuzzo G, Goronzy JJ , Yang H, et al. Monoclonal T-cell proliferation and plaque instability in acute coronary syndromes. Circulation , 2000 , 101 (25): 288322888.
[21] Geng YJ , Henderson L E , Levesque EB , et al. Fas is expressed in human at herosclerotic intima and promotes apoptosis of cytokine-primed human vascular smoot h muscle cells. Arterioscler Thromb Vasc Biol, 1997 ,17(10): 220022208.
[22] Wright DA , Futcher B , Ghosh P , et al . Association of human fas (CD95) wit h a ubiquitin-conjugating enzyme (UBC-FAP) . J Biol Chem , 1996 , 271 (49): 31037231043.
[23] Kikuchi J , Furukawa Y, Kubo N , et al . Induction of ubiquitin conjugating enzyme by aggregated low density lipoprotein in human macrophages and it's implications forat herosclerosis. Arterioscler Thromb Vasc Bio , 2000 , 20 (1) : 1282134.
[24] Muller S , Hoege C , Pyrowolakis G, et al . SUMO ubiquitinps mysterious cousin. Nat Rev Mol Cell Biol, 2001 , 2 (3): 2022210.
[25] Herrmann J , Edwards WD , Schwartz RS , et al. Increased ubiquitin immunoreactivity in unstable at herosclerotic plaques associated with acute coronary syndromes. J Am Coll Cardiol ,2002 , 40 (11): 191921927.
[26] Meiners S , Laule M, Rot her W, et al. Ubiquitin-proteasome pathway as a new target for the prevention of restenosis. Circulation , 2002,105:4832489.
[27] Hon WC , Wil son MI , Harlos K, et al . St ructural basis for the recognition of hydroxyproline in HIF-1 alpha by pVHL. Nature ,2002 ,417 (6892): 9752978.
[28] Kwon YT , Kashina AS , Davydov IV , et al . An essential role of Nterminal arginylation in cardiovascular development. Science, 2002 , 297 (5578): 96299.
[29] David M. Eisenmann. Wnt signaling. Wormbook, 2005, 1-17.
[30] Cadigan K, Nusse R. WNT signaling: a common theme in animal development. Genes Dev, 1997, 11:3286-3305.
[31] Brandon C, Eisenberg L M, Eisenberg C A. WNT signaling modulates the diversification of hematopoietic cells. Blood, 2000, 96:4132-4141.
[32] Smalley M J, Dale T C. WNT signaling in mammalian development and cancer. Cancer Metastasis Rev, 1999, 18:215-230.
[33] Polakis P. WNT signaling and cancer. Genes Dev, 2000, 14:1837-1851.
[34] De Ferrari G V, Inestrosa N C. WNT signaling function in Alzheimer's disease. Brain Res Rev, 2000, 33:1-12.
[35] Morin P J. Beta-catenin signaling and cancer. Bioessays, 1999, 21:1021-1030.
[36] Wodarz, A., Nusse, R. Mechanisms of Wnt signaling in development. A. Rev. Cell Dev. Biol. 1998, 14:59-88.
[37] Peifer, M., Polakis, P. Wnt signaling in oncogenesis and embryogen-esis a look outside the nucleus. Science 2000, 287(5458): 1606-1609.
[38] Cavallo R, Cox R, Moline M, Roose J, Polevoy G, et al. Drosophila TCF and Groucho interact to repress wingless signaling activity. Nature, 1998, 395:604-608.
[39] Kuhl, M., Sheldahl, L.C., Park, M., Miller, J.R., and Moon, R.T. The Wnt/Ca2+ pathway: a new vertebrate Wnt signaling pathway takes shape. Trends Genet, 2000, 16:279-283.
[40] Veeman, M.T., Axelrod, J.D., and Moon, R.T. A second canon. Functions and mechanisms of β-catenin-independent Wnt signaling. Dev. Cell, 2003, 5:367-377.
[41] Kuhl M, Sheldahl L C, Park M, Miller JR, Moon RT. The Wnt/Ca2+ pathway: a new vertebrate Wnt signaling pathway takes shape. Trends Genet, 2000, 16(7):279-83.
[42] Wu X, Park M, et al. The wingless signaling pathway is directly involved in Drosophila heart development. Development Biology, 1996, 177:104-116.
[43] Wu X, Golden K, Bodmer R. Heart development in Drosophila requires the polarity gene wingless. Development Biology, 1995, 169:619-628.
[44] Adell T, Nefkens I, Muller W E. Polarity factor 'Frizzled' in the dem- osponge Suberites domuncula identification, expression and localization of the receptor in the epithelium/pinacoderm (1). FEBS Lett, 2003, 554:363-368.
[45] Cadigan K M, Fish M P, Rulifson E J, Nusse R. Wingless repression of Drosophila frizzled 2 expression shapes the Wingless morphogen gradient in the wing. Cell, 1998, 93:767-777.
[46] Chen C M, Struhl G. Wingless transduction by the Frizzled and Friz- zled2 protein of Drosophila. Development, 1999, 126: 5441-5452.
[47]Amit S, Hatzubai A, Birman Y, Andersen J S, Ben-Shushan E, et al. Axin-mediated CKI phosphorylation of beta-catenin at Ser45: a molecular switch for the WNT pathway. Genes Dev, 2002, 16:1066-1076.
[48] Chen W, Guttridge D C, You Z, et al. WNT-1 signaling inhibits apo- ptosis by activating beta-catenin/T cell factor-mediated transcription. JCell Biol, 2001,152:87-96.
[49] Danielian P S, McMahon A P. Engrailen-1 as a target of the WNT-1 signaling pathway in vertebrate midbrain development. Nature, 1996, 383:332-334.
[50] Peter Maye, Jie Zheng, Lin Li, and Dianqing Wu. Multiple Mechanisms for Wntl 1-mediated Repression of the Canonical Wnt Signaling Pathway. J. Biol. Chem., 29(23):24659-24665.
[51] Aulehla A, Wehrle C, Brand-Saberi B, Kemler R, Gossler A, et al. WNT3a plays a major role in the segmentation clock controlling somitogenesis. Dev Cell, 2003, 4:395-406.
[52] Gagne J M, Downes B P, Shiu S H, Durski A M, Vierstra R D. The F-box subunit of the SCF E3 complex is encoded by a diverse superfamily of genes in Arabidopsis. Proc Natl Acad Sci USA, 2002, 99(17): 11519-11524.
[53] Risseeuw E P, Daskalchuk T E, Banks T W, Liu E, Cotelesage J, Hellmann H, Estelle M, Somers D E, Crosby W L. Protein interaction analysis of SCF ubiquitin E3 ligase subunits from Arabidopsis. Plant J, 2003, 34(6): 753-767.
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[57] Matsuzawa S I,Reed J C Siah—1.SIP. and Ebi Collaborate in a Novel Pathway for 8 Catenin Degradation Linked to p53 Responses. Mol Cell, 2001.7(5):915-926
[2] Robinson PA, Ardley HC. Ubiquitin2p rotein ligases. J Cell Sci, 2004, 1170:5191-5194.
[3] Zheng N, Schulman BA, Song L, et al. Structure of the Cull- Rbxl- Skpl-F boxSkp2 SCF ubiquitin ligase complex. Nature, 2002, 416: 703-709.
[4] Passmore LA, Booth CR, Venien2Bryan C, et al. Structural analysis of the anaphase-promoting complex reveals multiple active sites and insights into polyubiquitylation. Mol Cell, 2005, 20: 855-866.
[5] Hoppe T. Multiubiquitylation by E4 enzymes: 'one size' doesn't fit all. Trends Biochem Sci, 2005, 30:183-187.
[6] HochstrasserM. L ingering mysteries of ubiquitin2chain assembly. Cell, 2006, 124: 27-34.
[7] Nijman SM, Luna2VargasMP, Velds A, et al. A genomic and functional inventory of deubiquitinating enzymes. Cell, 2005, 123: 773-786.
[8] Welchman RL, Gordon C, Mayer RJ. Ubiquitin and ubiquitin like proteins as multifunctional signals. Nat Rev Mol Cell Biol, 2005, 6: 599-609.
[9] Pickart CM, EddinsMJ. Ubiquitin: structures, functions, mechanisms. Biochem Biophys Acta, 2004,1695: 55-72.
[10] Zavrski I, Jakob C, Schmid P, et al. Proteasome: an emerging target for cancer therapy. AnticancerDrugs, 2005, 16: 475-481.
[11] Ciechanover A , Orian A , Schwartz AL. The ubiquitin-mediated proteolytic pathway:mode of action and clinical implications. J Cell Biochem , 2000 , 34 (Suppl): 40251.
[12] Yamamoto Y, Gaynor RB. Therapeutic potential of inhibition of the NF-kappaB pathway in the treatment of inflammation and cancer . J Clin Invest, 2001 , 107 (2): 1352142.
[13] Herrmann J , Gulati R , Napoli C , et al . Oxidative stress-related increase in ubiquitination in early coronary at herosclerosis. FASEB J , 2003 , 17 (12): 173021732.
[14] Friguet B , Bulteau AL , Conconi M , et al . Redox cont rol of the 20S proteasome. Met hods Enzymol, 2002 , 353 : 2532262.
[15] Bulteau AL , Lundberg KC , Humphries KM , et al . Oxidative modification and inactivation of the proteasome during coronary occlusion/ reperfusion. J Biol Chem , 2001 , 276 ( 32 ) : 30057230063.
[16] Vieira O , Escargueil2Blanc I , J u rgens G, et al . Oxidized LDLs alter the activity of the ubiquitin-proteasome pathway: potential role in oxidized LDL-induced apoptosis. FASEB J , 2000 , 14(3) : 5322542.
[17] Hansson GK. Immune mechanisms in atherosclerosis , Arterio-scler Thromb Vasc Biol, 2001 , 21 (12): 187621890.
[18] Libby P. Changing concept s of at herogenesis. J Intern Med ,2000 , 247 (3): 3492358.
[19] Herrmann J , Edwards WD, Schwartz RS , et al. Increasedubiquitin immunoreactivity in unstable at herosclerotic plaques associated wit h acute coronary syndromes. J Am coll Cardiol ,2002 , 40 : 191921927.
[20] Liuzzo G, Goronzy JJ , Yang H, et al. Monoclonal T-cell proliferation and plaque instability in acute coronary syndromes. Circulation , 2000 , 101 (25): 288322888.
[21] Geng YJ , Henderson L E , Levesque EB , et al. Fas is expressed in human at herosclerotic intima and promotes apoptosis of cytokine-primed human vascular smoot h muscle cells. Arterioscler Thromb Vasc Biol, 1997 ,17(10): 220022208.
[22] Wright DA , Futcher B , Ghosh P , et al . Association of human fas (CD95) wit h a ubiquitin-conjugating enzyme (UBC-FAP) . J Biol Chem , 1996 , 271 (49): 31037231043.
[23] Kikuchi J , Furukawa Y, Kubo N , et al . Induction of ubiquitin conjugating enzyme by aggregated low density lipoprotein in human macrophages and it's implications forat herosclerosis. Arterioscler Thromb Vasc Bio , 2000 , 20 (1) : 1282134.
[24] Muller S , Hoege C , Pyrowolakis G, et al . SUMO ubiquitinps mysterious cousin. Nat Rev Mol Cell Biol, 2001 , 2 (3): 2022210.
[25] Herrmann J , Edwards WD , Schwartz RS , et al. Increased ubiquitin immunoreactivity in unstable at herosclerotic plaques associated with acute coronary syndromes. J Am Coll Cardiol ,2002 , 40 (11): 191921927.
[26] Meiners S , Laule M, Rot her W, et al. Ubiquitin-proteasome pathway as a new target for the prevention of restenosis. Circulation , 2002,105:4832489.
[27] Hon WC , Wil son MI , Harlos K, et al . St ructural basis for the recognition of hydroxyproline in HIF-1 alpha by pVHL. Nature ,2002 ,417 (6892): 9752978.
[28] Kwon YT , Kashina AS , Davydov IV , et al . An essential role of Nterminal arginylation in cardiovascular development. Science, 2002 , 297 (5578): 96299.
[29] David M. Eisenmann. Wnt signaling. Wormbook, 2005, 1-17.
[30] Cadigan K, Nusse R. WNT signaling: a common theme in animal development. Genes Dev, 1997, 11:3286-3305.
[31] Brandon C, Eisenberg L M, Eisenberg C A. WNT signaling modulates the diversification of hematopoietic cells. Blood, 2000, 96:4132-4141.
[32] Smalley M J, Dale T C. WNT signaling in mammalian development and cancer. Cancer Metastasis Rev, 1999, 18:215-230.
[33] Polakis P. WNT signaling and cancer. Genes Dev, 2000, 14:1837-1851.
[34] De Ferrari G V, Inestrosa N C. WNT signaling function in Alzheimer's disease. Brain Res Rev, 2000, 33:1-12.
[35] Morin P J. Beta-catenin signaling and cancer. Bioessays, 1999, 21:1021-1030.
[36] Wodarz, A., Nusse, R. Mechanisms of Wnt signaling in development. A. Rev. Cell Dev. Biol. 1998, 14:59-88.
[37] Peifer, M., Polakis, P. Wnt signaling in oncogenesis and embryogen-esis a look outside the nucleus. Science 2000, 287(5458): 1606-1609.
[38] Cavallo R, Cox R, Moline M, Roose J, Polevoy G, et al. Drosophila TCF and Groucho interact to repress wingless signaling activity. Nature, 1998, 395:604-608.
[39] Kuhl, M., Sheldahl, L.C., Park, M., Miller, J.R., and Moon, R.T. The Wnt/Ca2+ pathway: a new vertebrate Wnt signaling pathway takes shape. Trends Genet, 2000, 16:279-283.
[40] Veeman, M.T., Axelrod, J.D., and Moon, R.T. A second canon. Functions and mechanisms of β-catenin-independent Wnt signaling. Dev. Cell, 2003, 5:367-377.
[41] Kuhl M, Sheldahl L C, Park M, Miller JR, Moon RT. The Wnt/Ca2+ pathway: a new vertebrate Wnt signaling pathway takes shape. Trends Genet, 2000, 16(7):279-83.
[42] Wu X, Park M, et al. The wingless signaling pathway is directly involved in Drosophila heart development. Development Biology, 1996, 177:104-116.
[43] Wu X, Golden K, Bodmer R. Heart development in Drosophila requires the polarity gene wingless. Development Biology, 1995, 169:619-628.
[44] Adell T, Nefkens I, Muller W E. Polarity factor 'Frizzled' in the dem- osponge Suberites domuncula identification, expression and localization of the receptor in the epithelium/pinacoderm (1). FEBS Lett, 2003, 554:363-368.
[45] Cadigan K M, Fish M P, Rulifson E J, Nusse R. Wingless repression of Drosophila frizzled 2 expression shapes the Wingless morphogen gradient in the wing. Cell, 1998, 93:767-777.
[46] Chen C M, Struhl G. Wingless transduction by the Frizzled and Friz- zled2 protein of Drosophila. Development, 1999, 126: 5441-5452.
[47]Amit S, Hatzubai A, Birman Y, Andersen J S, Ben-Shushan E, et al. Axin-mediated CKI phosphorylation of beta-catenin at Ser45: a molecular switch for the WNT pathway. Genes Dev, 2002, 16:1066-1076.
[48] Chen W, Guttridge D C, You Z, et al. WNT-1 signaling inhibits apo- ptosis by activating beta-catenin/T cell factor-mediated transcription. JCell Biol, 2001,152:87-96.
[49] Danielian P S, McMahon A P. Engrailen-1 as a target of the WNT-1 signaling pathway in vertebrate midbrain development. Nature, 1996, 383:332-334.
[50] Peter Maye, Jie Zheng, Lin Li, and Dianqing Wu. Multiple Mechanisms for Wntl 1-mediated Repression of the Canonical Wnt Signaling Pathway. J. Biol. Chem., 29(23):24659-24665.
[51] Aulehla A, Wehrle C, Brand-Saberi B, Kemler R, Gossler A, et al. WNT3a plays a major role in the segmentation clock controlling somitogenesis. Dev Cell, 2003, 4:395-406.
[52] Gagne J M, Downes B P, Shiu S H, Durski A M, Vierstra R D. The F-box subunit of the SCF E3 complex is encoded by a diverse superfamily of genes in Arabidopsis. Proc Natl Acad Sci USA, 2002, 99(17): 11519-11524.
[53] Risseeuw E P, Daskalchuk T E, Banks T W, Liu E, Cotelesage J, Hellmann H, Estelle M, Somers D E, Crosby W L. Protein interaction analysis of SCF ubiquitin E3 ligase subunits from Arabidopsis. Plant J, 2003, 34(6): 753-767.
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