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A targeted gene expression system using the tryptophan repressor in zebrafish shows no silencing in subsequent generations.

ABSTRACT: The ability to visualize and manipulate cell fate and gene expression in specific cell populations has made gene expression systems valuable tools in developmental biology studies. Here, we describe a new system that uses the E. coli tryptophan repressor and its upstream activation sequence (TrpR/tUAS) to drive gene expression in stable zebrafish transgenic lines and in mammalian cells. We show that TrpR/tUAS transgenes are not silenced in subsequent generations of zebrafish, which is a major improvement over some of the existing systems, such as Gal4/gUAS and the Q-system. TrpR transcriptional activity can be tuned by mutations in its DNA-binding domain, or silenced by Gal80 when fused to the Gal4 activation domain. In cases in which more than one cell population needs to be manipulated, TrpR/tUAS can be used in combination with other, existing systems.

SUBMITTER: Suli A

PROVIDER: S-EPMC3929415 | biostudies-literature | 2014 Mar

REPOSITORIES: biostudies-literature

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A targeted gene expression system using the tryptophan repressor in zebrafish shows no silencing in subsequent generations.

Suli Arminda A Guler Ali D AD Raible David W DW Kimelman David D

Development (Cambridge, England) 20140301 5

The ability to visualize and manipulate cell fate and gene expression in specific cell populations has made gene expression systems valuable tools in developmental biology studies. Here, we describe a new system that uses the E. coli tryptophan repressor and its upstream activation sequence (TrpR/tUAS) to drive gene expression in stable zebrafish transgenic lines and in mammalian cells. We show that TrpR/tUAS transgenes are not silenced in subsequent generations of zebrafish, which is a major im ...[more]

PMID: 24550120

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