摘要
表皮生长因子(EGF)具有促进多种细胞增殖的作用, 尤其在维持消化道黏膜完整和促进消化道溃疡愈合方面作用巨大。以前的研究多集中在细菌和酵母中表达, 本研究试图以番茄作为生物反应器生产重组人 EGF, 使之成本降低, 应用方便。依据人 EGF 的基因序列, 设计合成了番茄密码子偏爱的人 EGF 基因, 并将其构建到植物表达载体 pCAMBIA2300 中, 通过农杆菌介导得到了含有人 EGF 基因的转基因番茄。放射免疫法检测到每克鲜重果实中的表达量达 3.48 ± 1.01 ng。将果汁灌喂小白鼠 15 天(相当于每鼠每天喂服 24 ng rhEGF)能显著抵抗酒精引起的胃溃疡形成, 溃疡指数由 42.20 ± 18.13 下降为 16.25 ± 9.57。
The epidermal growth factor （EGF） has been shown to promote the proliferation of various types of cells, to maintain the physiological function of the mucosa of the digestive tract, and to promote the healing of the gastric and duodenal ulcers. It has been expressed in many types of bacteria and yeasts. In this article, a bio-reactor was constructed, namely, the human EGF （hEGF） transgenic mini-tomato. On the basis of hEGF gene sequence, a tomato codon preference hEGF gene was chemically synthesized, and it was constructed into the plant expression vector pCAMBIA2300. The transgenic tomato plants containing gene hEGF were obtained through Agrobacterium-mediated transformation. The expression product was determined by radioimmunoassay （RIA） and showed a yield of 3.48± 1.01 ng/g fresh fruits. The intragastric gavage （ig） administration of the rhEGF-containing juice of the transgenic tomato （equivalent to 24 ng rhEGF per mouse a day） for 15 days could significantly protect mice against the alcohol-induced ulceration. The ulcer index, expressed as a degree of the stomach lesion, decreased from 42.20 ±18.13 to 16.25 ±9.57.
基金
This work was supported by the Innovation Group Development Project of the Ministry of Education of China (No. IRT0435).
