title: Production of transgenic chickens expressing a tetracycline-inducible GFP gene.
abstract: 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.
authors.affiliation: Department of Physiology, Catholic University of Daegu School of Medicine, Daegu, Republic of Korea.
authors.forename: Mo Sun
authors.initials: MS
authors.lastname: Kwon
authors.forename: Bon Chul
authors.initials: BC
authors.lastname: Koo
authors.forename: Ji Yeol
authors.initials: JY
authors.lastname: Roh
authors.forename: Minjee
authors.initials: M
authors.lastname: Kim
authors.forename: Jin-Hoi
authors.initials: JH
authors.lastname: Kim
authors.forename: Teoan
authors.initials: T
authors.lastname: Kim
mesh_terms: D000818:Animals; D030801:Animals, Genetically Modified; D002645:Chickens / Q000235:genetics*; D015870:Gene Expression / Q000187:drug effects*; D018014:Gene Transfer Techniques; D049452:Green Fluorescent Proteins / Q000235:genetics*; D023421:Models, Animal; D011401:Promoter Regions, Genetic / Q000187:drug effects; D013752:Tetracycline / Q000494:pharmacology*
chemical_list: D049452:Green Fluorescent Proteins; D013752:Tetracycline