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CTD kinase associated with yeast RNA polymerase II initiation factor b
1Department of Cell Biology, Stanford University School of Medicine, California 94305.
Cell
|December 20, 1991
Summary
Yeast general initiation factor b possesses kinase activity that phosphorylates RNA polymerase II
Area of Science:
- Molecular Biology
- Biochemistry
- Transcription Factors
Background:
- RNA polymerase II C-terminal domain (CTD) phosphorylation is crucial for transcription.
- General transcription initiation factors play essential roles in regulating gene expression.
Purpose of the Study:
- To identify and characterize the kinase activity associated with yeast general initiation factor b.
- To investigate the role of this kinase in transcription initiation.
Main Methods:
- Cofractionation based on size and charge.
- Mild heat inactivation.
- Kinase assays.
- DNA-dependent ATPase assays.
Main Results:
- A kinase activity specific for the RNA polymerase II CTD was found to be associated with yeast general initiation factor b.
- This kinase phosphorylates the CTD at multiple sites.
- Factor b also exhibits DNA-dependent ATPase activity.
- Both activities share nucleotide requirements with transcription initiation.
Conclusions:
- Phosphorylation of the CTD by factor b is involved in transcription initiation.
- Factor b possesses catalytic activities essential for the transcription initiation process.
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