https://www.abbs.info
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ISSN
1672-9145
Acta Biochim Biophys Sin
2005, 37(2): 133–138
CN 31-1940/Q
Temporal Control of Cre Recombinase-mediated in Vitro DNA
Recombination by Tet-on Gene Expression System
Zhong-Min GUO, Kang XU1, Ying YUE, Bing HUANG, Xin-Yan
DENG, N-Qi ZHONG, Xun HONG, Xi-Gu CHEN*,
and Dong XIAO*
Center of
Experimental Animals, Sun Yat-Sen (Zhongshan) University, Guangzhou 510080,
China;
1The First Affiliated Hospital of Sun Yat-Sen
University, Sun Yat-Sen University, Guangzhou 510080, China
Abstract Conditional gene
expression and gene deletion are important experimental approaches for
examining the functions of particular gene products in mouse models. These
strategies exploiting Cre-mediated site-specific DNA recombination have been
incorporated into transgenic and gene-targeting procedures to allow in vivo manipulation
of DNA in embryonic stem cells (ES cells) or living animals. The Cre/lox P
system has become widely used in conditional gene targeting, conditional gene
repair and activation, inducible chromosome translocation, and chromosome
engineering. In this project, we have employed the universal transgenic system
and the liver-specific promoter system for tightly temporal and liver-specific
control of Cre gene expression in mice that (1) integrates the advantages of
the Tet-on gene expression system and Cre/lox P site-mediated gene
activation, and (2) simplifies the scheme of animal crosses through a
combination of two control elements in a single transgene. A liver-specific apoE
promoter was inserted into the promoter cloning site upstream of the rtTA
cassette of pCore construct to generate the transgene construct
pApoErtTA-tetO-Cre, followed by demonstrating stringent regulation of
doxycycline (Dox)-induced Cre-mediated recombination in the lox P-flanked
transcription STOP cassette-modified BEL-7402 cells. That is to say, in the
absence of Dox, the Cre gene is not expressed and will not induce
site-specific recombination between two lox P sites, whereas on exposure
to Dox, the Cre gene will be expressed and the recombination will occur.
Together, these data indicate that the Tet-on gene expression system is able to
successfully and stringently control Cre expression in vitro,
which lays a solid foundation for efficient and spatio-temporal Cre gene
activation in transgenic mice.
Key words conditional gene
regulation; Cre recombinase; human apolipoprotein E gene (apoE)
promoter; Tet-on gene expression system; universal transgenic system
—————–
Received: July 12, 2004 Accepted: December 22, 2004
This work was supported by the grants from the National Natural
Science Foundation of China (No. 30271177 and No. 39870676), the Natural
Science Foundation of Guangdong Province (No. 021903), and the Postdoctoral
Fellowship Foundation of China (Series 29)
*Corresponding authors: Tel, 86-20-87330450/87331393; Fax,
86-20-87331230; E-mail, [email protected]
& [email protected]