Profilin oligomerization and its effect on poly (L-proline) binding and phosphorylation
Radhika V Korupolu1, M S Achary, F Aneesa
1Department of Biochemistry, Osmania University, Hyderabad 500007, India.
International Journal of Biological Macromolecules
|June 16, 2009
Summary
Profilin protein oligomers, dimers and tetramers, show weak poly (L-proline) binding. Tetramers are preferentially phosphorylated over monomers, with accessible S137 sites for PKC.
Area of Science:
- Biochemistry and Molecular Biology
- Cytoskeletal Protein Research
Background:
- Profilin is a key cytoskeletal protein involved in actin dynamics.
- It interacts with actin, phosphoinositides, and poly (L-proline).
Purpose of the Study:
- To investigate the oligomeric states of profilin (dimer and tetramer).
- To understand the impact of oligomerization on poly (L-proline) binding.
- To examine the phosphorylation patterns of profilin oligomers.
Main Methods:
- Experimental biochemical assays.
- In silico computational studies.
- Phosphorylation site analysis.
Main Results:
- Profilin exists in dimer and tetramer forms.
- Profilin oligomers exhibit weak affinity for poly (L-proline) due to unavailable binding sites.
- Profilin tetramers are preferentially phosphorylated over monomers.
- The protein kinase C (PKC) phosphorylation site S137 is accessible in tetramers but buried in dimers.
Conclusions:
- Oligomerization state significantly affects profilin's functional properties, including ligand binding and phosphorylation.
- Tetrameric profilin's accessible S137 site suggests a regulatory role for PKC-mediated phosphorylation in tetramers.
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