title: Generation and characterization of a transgenic zebrafish expressing the reverse tetracycline transactivator.
abstract: Conditional expression of a target gene during zebrafish development is a powerful approach to elucidate gene functions. The tetracycline-controlled systems have been successfully used in the modulation of gene expression in mammalian cells, but few lines of zebrafish carrying these systems are currently available. In this study, we had generated a stable transgenic zebrafish line that ubiquitously expressed the second-generation of reverse Tet transactivator (rtTA-M2). Southern blotting analysis and high-throughput genome sequencing verified that a single copy of rtTA-M2 gene had stably integrated into the zebrafish genome. After induction with doxycycline (Dox), a strong green fluorescent protein (GFP) was seen in rtTA-transgenic eggs injected with pTRE-EGFP plasmids. The fluorescent signal gradually decreased after the withdrawal of Dox and disappeared. However, leaky expression of GFP was undetectable before Dox-induction. Additionally, transgenic embryos expressing rtTA-M2 exhibited no obvious defects in morphological phenotypes, hatching behavior and expression patterns of developmental marker genes, suggesting that rtTA-M2 had little effect on the development of transgenic zebrafish. Moreover, expressed Dickkopf-1 (DKK1) in pTRE-DKK1-injected embryos led to alterations in the expression of marker genes associated with Wnt signaling. Thus, this rtTA-transgenic zebrafish can be utilized to dissect functions of genes in a temporal manner.
authors.affiliation: The Key Laboratory of Aquatic Biodiversity and Conservation of Chinese Academy of Sciences, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China; University of Chinese Academy of Sciences, Beijing 100049, China.
authors.forename: Qilin
authors.initials: Q
authors.lastname: Gu
authors.forename: Xiaojie
authors.initials: X
authors.lastname: Yang
authors.forename: Xiaozhen
authors.initials: X
authors.lastname: He
authors.forename: Qing
authors.initials: Q
authors.lastname: Li
authors.forename: Zongbin
authors.initials: Z
authors.lastname: Cui
mesh_terms: D000818:Animals; D030801:Animals, Genetically Modified / Q000235:genetics; D004318:Doxycycline / Q000494:pharmacology; D013752:Tetracycline / Q000494:pharmacology; D015534:Trans-Activators / Q000235:genetics*; D019076:Transgenes; D015027:Zebrafish
chemical_list: D015534:Trans-Activators; D013752:Tetracycline; D004318:Doxycycline
keywords: Doxycycline; Reverse Tet transactivator; Tet-on system; Transgene; Zebrafish