title: [Deletion of marker gene in transgenic goat by Cre/LoxP system].
abstract: In producing transgenic livestock, selectable marker genes (SMGs) are usually used to screen transgenic cells from numerous normal cells. That results in SMGs integrating into the genome and transmitting to offspring. In fact, SMGs could dramatically affect gene regulation at integration sites and also make the safety evaluation of transgenic animals complicated. In order to determine the deletion time and methods in the process of producing transgenic goats, the feasibility of deleting SMGs was explored by Cre/LoxP before or after somatic cell cloning. In addition, we compared the efficiency of protein transduction with plasmids co-transduction. We could delete 43.9% SMGs after screening out the transgenic cell clones, but these cells could not be applied to somatic cells cloning because of serious aging after two gene modifications. The SMG-free cells suitable for nuclear transfer were accessible by using the cells of transgenic goats, but this approach was more time consuming. Finally, we found that the Cre plasmid could delete SMGs with an efficiency of 7.81%, but about 30% in SMG-free cells had sequences of Cre plasmid. Compared with Cre plasmid, the integration of new exogenous gene could be avoided by TAT-CRE protein transduction, and the deletion rate of TAT-CRE transduction was between 43.9 and 72.8%. Therefore, TAT-Cre transduction could be an effective method for deleting selectable marker genes.
authors.forename: Chong
authors.initials: C
authors.lastname: Lan
authors.forename: Lina
authors.initials: L
authors.lastname: Ren
authors.forename: Min
authors.initials: M
authors.lastname: Wu
authors.forename: Siguo
authors.initials: S
authors.lastname: Liu
authors.forename: Guohui
authors.initials: G
authors.lastname: Liu
authors.forename: Xujun
authors.initials: X
authors.lastname: Xu
authors.forename: Jianquan
authors.initials: J
authors.lastname: Chen
authors.forename: Hengdong
authors.initials: H
authors.lastname: Ma
authors.forename: Guoxiang
authors.initials: G
authors.lastname: Cheng
mesh_terms: D000818:Animals; D030801:Animals, Genetically Modified / Q000235:genetics*; D019976:Cloning, Organism / Q000662:veterinary*; D055786:Gene Knockout Techniques; D018390:Gene Targeting / Q000379:methods*; D017930:Genes, Reporter; D005818:Genetic Engineering; D005822:Genetic Vectors / Q000235:genetics; D006041:Goats / Q000235:genetics*; D019426:Integrases / Q000737:chemistry / Q000378:metabolism*; D011995:Recombination, Genetic; D019076:Transgenes / Q000235:genetics
chemical_list: C045073:Cre recombinase; D019426:Integrases