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Mutants of GAL4 protein altered in an activation function
1Department of Biochemistry and Molecular Biology, Harvard University, Cambridge, Massachusetts 02138.
Cell
|October 9, 1987
Summary
Mutations in GAL4
Area of Science:
- Molecular Biology
- Yeast Genetics
Background:
- GAL4 is a transcription factor that regulates gene expression in yeast.
- Activating region I (AR I) of GAL4 is crucial for its transcriptional activity.
Purpose of the Study:
- To investigate the relationship between the acidity of GAL4's Activating Region I and its transcriptional activation function.
- To identify specific mutations affecting AR I's function and correlate them with changes in acidity.
Main Methods:
- Site-directed mutagenesis was used to introduce changes within and around AR I of GAL4.
- Transcriptional activation assays in yeast were performed to assess the function of the generated mutants.
Main Results:
- Mutations that enhanced transcriptional activation invariably increased the acidity of AR I.
- Mutations that decreased activation function showed a variable effect on acidity; some decreased it, while others did not.
Conclusions:
- The acidity of GAL4's Activating Region I is a critical determinant of its transcriptional activation function.
- Modulating the acidity of AR I provides a mechanism for altering GAL4's regulatory activity.
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