關于人野生型p53腫瘤抑制基因在煙草中的遺傳轉化
康杰芳 王喆之
【摘要】 目的: 構建人野生型p53腫瘤抑制基因的植物表達載體,并建立p53轉基因煙草植株. 方法: 將人野生型p53腫瘤抑制基因編碼區克隆于pUC19, pBI426和pCAMBIA2301載體,構建含人野生型p53基因的植物表達載體pCAMBIA2301/p53,p53基因由2×CaMV 35S啟動子控制表達. 利用葉盤共培養法經根瘤農桿菌EHA105介導轉化煙草,獲得轉基因煙草植株;用組織化學法,PCR、Southern雜交檢測轉基因煙草植株. 結果: 經組織化學法,PCR, Southern雜交檢測表明人野生型p53基因已整合到轉基因煙草植株的基因組中,并獲得了的轉p53基因煙草植株. 結論: 成功建立了含人野生型p53基因的轉基因煙草植株,為進一步檢測p53基因的生物活性和開辟生產藥用蛋白的新途徑奠定了基礎. 【關鍵詞】 人野生型p53基因;轉基因煙草;根瘤農桿菌;基因轉化;抗菌藥 【Abstract】AIM: To construct the plant transformation vector containing human wildtype p53 tumor suppressor gene and establish human wildtype p53 transgenic tobacco plants. METHODS: The human wildtype p53 coding sequence was subcloned into vectors pUC19, pBI426 and pCAMBIA2301 to obtain plant expression vector pCAMBIA2301/p53. TDNA regions of the pCAMBIA2301/p53 binary vector contained constitutive 2×Cauliflower mosaic virus (2×CaMV) 35S promoter, nopaline synthase terminator, and neomycin phosphotransferase Ⅱ(npt Ⅱ)gene, which allowed the selection of transformed plants against kanamycin. The tobacco (Nicotiana tobacum L.Cuttivar Xanthi) plants were transformed by cocultivating leaf discs method via Agrobacterium tumefaciens EHA105 harboring the plant expression vector. The generated transgenic tobacco plants were selected by kanamycin, and identified by histochemical assay, PCR, Southern blot. RESULTS: Histochemical assay, PCR and Southern blot analyses demonstrated the stable integration of the human wildtype p53 gene into the tobacco genome.Transgenic tobacco plant with p53 gene was obtained successfully. CONCLUSION: Transgenic wildtype p53 tobacco plants have been established, which can serve as a base for further studies on detecting the biological activities of p53 gene and exploiting the new way of producing pharmaceutical proteins. 【Keywords】 human wildtype p53 gene; transgenic tobacco; Agrobacterium tumefaciens; gene transformation; antibacterial agents 0引言 人類癌癥中最常見的基因改變是p53基因突變,它是癌基因研究中重要的腫瘤抑制基因之一,野生型p53基因與細胞周期的生長調節、細胞轉化的調節、DNA復制以及誘導細胞程序性死亡有著密切關系[1-2]. 本研究利用轉基因植物作為生物反應器的優點,將人野生型p53腫瘤抑制基因構建于植物表達載體,通過根瘤農桿菌介導的轉化方法將其轉入煙草,獲得表達人野生型p53基因的轉基因植株,為今后借助轉基因煙草或其它轉基因植物作為生物反應器生產人野生型p53蛋白奠定了基礎. 1材料和方法 1.1材料 1.1.1質粒、菌株人野生型p53腫瘤抑制基因由趙永同博士惠贈,植物表達載體pCAMBIA2301,根瘤農桿菌(Agrobacterium tumefaciens)EHA105,大腸桿菌(Ecoli.)DH5α,pUC19為本實驗室保存. 1.1.2主要試劑各種限制性酶、Tag聚合酶、質粒快速提取試劑盒、DNA膠回收試劑盒等購自TaKaRa公司和上海生工生物工程技術服務有限公司;高效地高辛 DNA標記檢測試劑盒購自Roche Molecular Biochemicals公司. 頭孢曲松鈉購自上海先鋒藥業公司;卡那霉素購自華美生物工程公司,其他常規試劑均為國產分析純試劑. 1.1.3培養基LB及MS 培養基按參考文獻方法配制[3]. 浸染培養基:MS0+ AS(400μmol/L)+ pluronic F68 (0.5 mg/L),AS和pluronic F68在浸染前加入. 共培養基:MS+BA(1 mg/L)+NAA(0.1 mg/L) + AS (400 μmol/L)+pluronic F68 (0.5 mg/L). 選擇培養基:MS+BA (1 mg/L)+ NAA (0.1 mg/L )+Kanamycin (100 mg/L)+頭孢曲松鈉. 頭孢曲松鈉濃度依次為50 mg/L, 100 mg/L, 150 mg/L, 200 mg/L, 300 mg/L, 400 mg/L, 500 mg/L, 600 mg/L. GUS顯色液按
[2]Mirza A, McGuirk M, Hockenberry TN, et al. Human surviving is negatively regulated by wild type p53 and participates in p53 dependent apoptotic pathway[J]. Oncogene, 2002,21(17):2613-2622.
[3]王關林,方宏筠. 植物基因工程原理和方法[M]. 北京: 科學出版社,2002:350-355.
[4]Jfferson RA. Assaying chimeric genes in plants: the GUS gene fusion system[J]. Plant Mol Biol Rep, 1987, 5(4): 387-405.
[5]Horsh RB, Fry JL, Hoffman NC, et al. A simple and general method for transfering genes into plants [J].Science, 1985,217:1229-1231.
[6]Fujiwara T, Grimm EA, Mukhopadhyay T, et al. A retroviral wildtype p53 expression vector penetrates human lung cancer spheroids and inhibits growth by inducing apoptosis[J]. Cancer Res, 1993,8:4129-4133.
[7]Toschi E, Rota R, Antonini A, et al. WildType p53 gene transfer inhibits invasion and reduces matrix metalloproteinase2 levels in p53mutated human melanoma cells[J]. J Invest Dermatol, 2000,114:1188-1194.
[8]程霞英,楊宗岐. 轉基因植物生產藥用蛋白研究進展[J]. 生物技術,2005,15(2):86-88.
[9]Okkel FT, Pederson MG, The toxicity to plant tissue and to Agrobacterium tumefaciens of some antibiotics[J]. Acta Hort, 1998,225:199-207.