Department of Physiology, Catholic University of Daegu School of Medicine, Daegu, Republic of Korea.
Biochem Biophys Res Commun. 2011 Jul 15;410(4):890-4. doi: 10.1016/j.bbrc.2011.06.088. Epub 2011 Jun 17.
There is much interest in using farm animals as 'bioreactors' to produce large quantities of biopharmaceuticals. However, uncontrolled constitutive expression of foreign genes have been known to cause serious physiological disturbances in transgenic animals. The objective of this study was to test the feasibility of the controllable expression of an exogenous gene in the chicken. A retrovirus vector was designed to express GFP (green fluorescent protein) and rtTA (reverse tetracycline-controlled transactivator) under the control of the tetracycline-inducible promoter and the PGK (phosphoglycerate kinase) promoter, respectively. G0 founder chickens were produced by infecting the blastoderm of freshly laid eggs with concentrated retrovirus vector. Feeding the chickens obtained with doxycycline, a tetracycline derivative, resulted in emission of green body color under fluorescent light, and no apparent significant physiological dysfunctions. Successful germline transmission of the exogenous gene was also confirmed. Expression of the GFP gene reverted to the pre-induction levels when doxycycline was removed from the diet. The results showed that a tetracycline-inducible expression system in transgenic animals might be a promising solution to minimize physiological disturbances caused by the transgene.
人们对于利用农场动物作为“生物反应器”来生产大量生物制药很感兴趣。然而，人们已经知道，外源基因的非受控组成型表达会导致转基因动物出现严重的生理紊乱。本研究的目的是测试在鸡中实现外源基因可控表达的可行性。设计了一种逆转录病毒载体，分别在四环素诱导启动子和 PGK（磷酸甘油酸激酶）启动子的控制下表达 GFP（绿色荧光蛋白）和 rtTA（四环素控制的反式激活因子）。通过感染刚产下的鸡蛋的囊胚，生产出 G0 创始鸡。用强力霉素（一种四环素衍生物）喂养获得的鸡，在荧光灯下会发出绿色体色，并且没有明显的明显的生理功能障碍。还证实了外源基因的成功种系传递。当从饮食中去除强力霉素时，GFP 基因的表达恢复到诱导前的水平。结果表明，在转基因动物中使用四环素诱导表达系统可能是一种有前途的解决方案，可以最大程度地减少转基因引起的生理紊乱。
