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GAL4 activates gene expression in mammalian cells
1Department of Biochemistry and Molecular Biology, Harvard University, Cambridge, Massachusetts 02138.
Cell
|January 29, 1988
Summary
The yeast transcription factor GAL4 activates gene expression in mammalian cells. Its activating regions and DNA-binding ability are crucial for this cross-species function.
Area of Science:
- Molecular Biology
- Gene Regulation
- Yeast Genetics
Background:
- GAL4 is a well-characterized transcription activator in yeast.
- The mouse mammary tumor virus (MMTV) promoter is a common reporter in gene expression studies.
- Understanding cross-species transcription factor function provides insights into conserved regulatory mechanisms.
Purpose of the Study:
- To investigate if the yeast transcription factor GAL4 can activate transcription in mammalian cells.
- To determine the functional domains of GAL4 required for activation in a mammalian system.
- To examine the synergistic effect of GAL4 and glucocorticoid receptor on the MMTV promoter.
Main Methods:
- Transfection of mammalian cells with plasmids containing the GAL4 DNA-binding sequence and reporter gene.
- Analysis of reporter gene expression.
- Use of GAL4 deletion mutants and a DNA-binding deficient mutant.
- Co-transfection with glucocorticoid receptor expression vector.
Main Results:
- GAL4 activates the MMTV promoter in mammalian cells.
- Activation requires a GAL4-binding sequence upstream of the promoter.
- Specific activating regions of GAL4 are conserved for function in mammalian cells.
- A GAL4 derivative that binds DNA but cannot activate in yeast also fails to activate in mammalian cells.
- GAL4 and glucocorticoid receptor exhibit synergistic activation of the MMTV promoter.
Conclusions:
- The GAL4 transcription factor can function in mammalian cells, indicating conserved regulatory principles.
- Specific domains within GAL4 are essential for its cross-species transcriptional activation.
- GAL4 and glucocorticoid receptor can cooperate to enhance gene expression.
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