Generation and characterization of a Tet-On (rtTA-M2) transgenic rat.
BACKGROUND
The tetracycline-inducible gene regulation system is a powerful tool that allows temporal and dose-dependent regulation of target transgene expression in vitro and in vivo. Several tetracycline-inducible transgenic mouse models have been described with ubiquitous or tissue-specific expression of tetracycline-transactivator (tTA), reverse tetracycline-transactivator (rtTA) or Tet repressor (TetR). Here we describe a Tet-On transgenic rat that ubiquitously expresses rtTA-M2 driven by the murine ROSA 26 promoter.


RESULTS
The homozygous rat line (ROSA-rtTA-M2) generated by lentiviral vector injection, has a single integration site and was derived from the offspring of a genetic mosaic founder with multiple transgene integrations. The rtTA-M2 transgene integrated into an intron of a putative gene on chromosome 2 and does not appear to affect the tissue-specificity or expression of that gene. Fibroblasts from the ROSA-rtTA-M2 rats were transduced with a TetO7/CMV-EGFP lentivirus and exhibited doxycycline dose-dependent expression of the EGFP reporter transgene, in vitro. In addition, doxycycline-inducible EGFP expression was observed, in vivo, when the TetO7/CMV-EGFP lentivirus was injected into testis, kidney and muscle tissues of ROSA-rtTA-M2 rats.


CONCLUSIONS
This conditional expression rat model may have application for transgenic overexpression or knockdown studies of gene function in development, disease and gene therapy.
Sheng
Yi
Y
Department of Obstetrics, Gynecology and Reproductive Sciences, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA.
Lin
Chih-Cheng
CC
Yue
Junming
J
Sukhwani
Meena
M
Shuttleworth
Jennifer J
JJ
Chu
Tianjiao
T
Orwig
Kyle E
KE
D000818:Animals; D002460:Cell Line; D005347:Fibroblasts; D005821:Genetic Techniques; D051379:Mice; D011401:Promoter Regions, Genetic; D051381:Rats / Q000235:genetics*; D055647:Rats, Transgenic; D013752:Tetracycline; D015534:Trans-Activators / Q000235:genetics
D015534:Trans-Activators; D013752:Tetracycline