T-REx cells are a type of mammalian cell line engineered for inducible protein expression. This means that the expression of a specific gene, introduced into the cell, can be controlled by adding or removing a specific molecule. Critically, T-REx cells stably express the tetracycline repressor protein. This protein acts as a molecular switch, regulating the transcription of a target gene.
How T-REx Cells Work
The system leverages a tetracycline-controlled transcriptional activation (Tet-On) system. The key components are:
- Tetracycline Repressor (TetR): This protein, constitutively expressed in T-REx cells, binds to a specific DNA sequence called the tetracycline operator (tetO).
- Tetracycline Operator (tetO): This DNA sequence is located upstream of the gene of interest in the expression vector. When TetR is bound, it prevents gene transcription.
- Tetracycline (or analog): Adding tetracycline (or a similar antibiotic like doxycycline) to the cell culture medium interferes with the binding of TetR to tetO, allowing transcription of the target gene. Removal of the tetracycline then allows TetR to bind again, switching off the gene.
This allows researchers to tightly control the expression of a gene of interest within the T-REx cell, ensuring precise control over protein production.
Several T-REx cell lines exist, such as the T-REx™-293 Cell Line, which simplifies the process of generating stable cell lines for inducible protein expression https://www.thermofisher.com/order/catalog/product/R71007. Other examples include the Flp-In™ T-REx™ 293 Cell Line, designed for rapid generation of stable cell lines ensuring homogeneous expression https://www.thermofisher.com/order/catalog/product/R78007. These lines are commonly used in research for various applications including studying gene function and producing recombinant proteins.
Advantages of Using T-REx Cells
- Tight control of gene expression: Allows precise regulation of protein levels.
- Stable expression: The tetracycline repressor is integrated into the cell's genome, ensuring consistent expression across generations.
- Simplified workflow: Compared to other inducible systems, T-REx simplifies the generation of stable cell lines.
