Overexpression of oncogenic Skp2 has been observed in vaious types of human tumor tissues and cell lines. Skp2 positively regulates the G_1-S transition as a member of the F-box family of substrate-regulation subunits of SCF ubiquitin-protein ligase complexes. To determine the further relationship between Skp2 and the G_2/M checkpoint,ectopic expression of Skp2 or inhibition of Skp2 expression by antisense oligodeoxynucleotides was performed. Our results indicated that overexpression of Skp2 may stimulate progression of cell cycle of HeLa cells dependent of its F-box structure,characterized by increase in the S population and decrease in G_2/M population. Skp2-antisense treatment not only inhibits proliferation of HeLa cells as determined by MTT, but also induces G_2/M arrest determined by FCM. The result by Western blotting shows p21,an important G_2/M checkpoint regulator,invovled in cell cycle progression as an effector of Skp2. Furthermore,the inverse relationship between Skp2 and p21 was consistant with the result from HeLa cells treated with actinomycin D. This study will be helpful to reveal molecular mechanisms of Skp2 regulation G_2/M checkpoint in HeLa cells.
QIAN Jun-Jie, SUN Guo-Jing, MENG Xiang-Bing, SONG Yi, MEI Zhu-Zhong, LIU Bin, DONG Yan, SUN Zhi-Xian *.
Effect of Skp2 on G_2/M Checkpoint of HeLa Cells[J]. Chinese Journal of Biochemistry and Molecular Biology, 2005, 21(05): 575-580
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参考文献
1 Zhang H,Kobayashi R,Galaktionov K,Beach D.p19Skp1and p45Skp2are essential elements of the cyclin A-CDK2S phase kinase.Cell,1995,82(6):915~925
2 Kornitzer D,Ciechanover A.Modes of regulation of ubiquitin-mediated protein degradation.J Cell Physiol,2000,182(1):1~11
3 DeSalle L M,Pagano M.Regulation of G1to S transition by the ubiquitin pathway.FEBSLett,2001,490(3):179~189
4 Yokoi S,Yasui K,Saito-Ohara F,Koshikawa K,Iizasa T,Fujisawa T,Terasaki T,Horii A,Takahashi T,Hirohashi S,Inazawa J.Anovel target gene,Skp2,within the5p13amplicon that is frequently detected in small cell lung cancers.AmJ Pathol,2002,161(1):207~216
5 Sana Y,Kohichiroh Y,Toshihiko I,Takashi T,Takehiko F,Johji I.Down-regulation of Skp2induces apoptosisinlung-cancer cells.Cancer Sci,2003,94(4):344~349
6 Lim MS,Adamson A,Lin Z,Perez-Oredonez B,Jordan R C,Tripp S,Perkins SL,Elenitoba-Johnson KS.Expression of Skp2,a p27(Kip1)ubiquitinligase,in malignant lymphoma:correlation with p27(Kip1)and proliferationindex.Blood,2002,100(8):2950~2956
7 Latres E,Chiarle R,Schulman B A,Pavletich NP,Pellicer A,Inghirami G,Pagano M.Role of the F-box protein Skp2inlymphomagenesis.Proc Natl Acad Sci USA,2001,98:2515~2520
8 钱俊杰,孙国敬,孟祥兵,宋宜,梅柱中,刘斌,董燕,孙志贤.HeLa细胞中Skp2的表达调控p21WAF/CIP1稳定性.中国生物化学与分子生物学报(Qian Jun-Jie,Sun Guo-Jing,Meng Xiang-Bin,Song Yi,Mei Zhu-Zhong,Liu Bin,Dong Yan,Sun Zhi-xian.Stability of p21WAF/CIP1regulated by Skp2in HeLa cells.Chin J Biochem Mol Biol),2004,20(6):732~737
9 宋宜,孟祥兵,梅柱中,刘斌,董燕,孙国敬,孙志贤.DNA损伤生物学反应中ATM对p21WAF/CIP1蛋白的直接磷酸化.中国生物化学与分子生物学报(Song Yi,Meng Xiang-Bin,Mei Zhu-Zhong,Liu Bin,Dong Yan,Sun Guo-Jing,Sun Zhi-Xian.Direct phosphorylation of p21WAF/CIP1with ATMin DNAdamage response.Chin J Biochem Mol Biol),2002,18(3):277~281
10 Lu L,Schulz H,Wolf D A.The F-box protein Skp2mediates androgen control of p27stability in LNCaP human prostate cancer cells.BMC Cell Biol,2002,3(1):22~34
11 Signoretti S,Di Marcotullio L,Richardson A,Ramaswamy S,Isaac B,Rue M,Monti F,Loda M,Pagano M.Oncogenic role of the ubiquitin ligase subunit Skp2in human breast cancer.J Clin Invest,2002,110(5):633~641
12 Nakayama K,Nagahama H,Minamishima Y A,Miyake S,Ishida N,Hatakeyama S,Kitagawa M,Iemura S,Natsume T,Nakayama KI.Skp2-mediated degradation of p27regulates progressioninto mitosis.Dev Cell,2004,6(5):661~672
13 Widlund HR,Horstmann MA,Price E R,Cui J,Lessnick S L,Wu M,He X,Fisher D E.Beta-catenin-induced melanoma growth requires the downstreamtarget Microphthalmia associated transcription factor.J Cell Biol,2002,158(6):1079~1087
14 Rossig L,Badorff C,Holzmann Y,Zeiher A M,Dimmeler S.Glycogen synthase kinase-3couples AKT-dependent signaling to the regulation of p21Cip1degradation.J Biol Chem,2002,277(12):9684~9689
15 Nalepa G,Wade Harper J.Therapeutic anti-cancer targets upstreamof the proteasome.Cancer Treat Rev,2003,29(1):49~57