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Updated: Aug 11, 2026
11:44
A High Resolution Method to Monitor Phosphorylation-dependent Activation of IRF3
Published on: January 24, 2016
C-terminal phosphorylation of the serum-response factor
R Janknecht1, W H Ernst, T Houthaeve
1Institute for Molecular Biology, Hannover Medical School, Germany.
European Journal of Biochemistry
|September 1, 1993
Summary
Serum-response factor (SRF) phosphorylation, particularly at C-terminal Ser253, influences transcriptional repression of the protooncogene c-fos. This finding expands understanding of SRF regulation beyond its N-terminal sites.
Area of Science:
- Molecular Biology
- Gene Regulation
Background:
- Serum-response factor (SRF) is crucial for regulating the protooncogene c-fos.
- SRF phosphorylation, especially in its N-terminal region, is known to affect its function.
- The precise role of C-terminal phosphorylation in SRF activity remains less understood.
Purpose of the Study:
- To investigate additional in vivo phosphorylation sites of SRF.
- To determine the functional impact of C-terminal SRF phosphorylation on c-fos regulation.
Main Methods:
- In vivo phosphorylation analysis of SRF.
- Microsequencing to identify phosphorylation sites.
- Site-directed mutagenesis to assess functional consequences.
- Analysis of DNA-binding and transactivation properties.
Main Results:
- Identified a novel C-terminal phosphorylation site at Ser253, a potential target for casein kinase II.
- Phosphorylation at Ser253 did not alter SRF's DNA-binding or transactivation capabilities.
- C-terminal phosphorylation at Ser253 was found to influence SRF's role in transcriptional repression.
Conclusions:
- C-terminal phosphorylation of SRF, specifically at Ser253, plays a role in modulating the basal repression of c-fos.
- This study expands the known regulatory mechanisms of SRF, highlighting the importance of its C-terminal modifications.
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