Dimerization of profilin II upon binding the (GP5)3 peptide from VASP overcomes the inhibition of actin nucleation by profilin II and thymosin beta4.
Jonckheere. V V; Lambrechts. A A; Vandekerckhove. J J; Ampe. C C
Key Findings
- Profilin II dimers bind the (GP5)3 VASP‑derived peptide with about 0.5 µM affinity.
- The peptide‑profilin II complex restores actin filament formation that is normally blocked by thymosin‑beta‑4 and profilin II.
- The rescue effect is lost when filament ends are capped and does not occur with profilin I, indicating specificity.
Practical Outcomes
- For biohackers, the findings are mainly mechanistic and don’t provide a direct supplement or dosing recommendation. It suggests that targeting profilin‑II interactions could be a future avenue for influencing muscle or cellular health, but no actionable steps are available now.
Summary
The study shows that a small peptide from the protein VASP can stick to another protein called profilin II, forming a dimer that cancels out the normal slowdown of actin building caused by profilin II and thymosin‑beta‑4, but this effect only happens in a test‑tube setting and doesn’t translate into a clear health or performance protocol.
Abstract
Profilin II dimers bind the (GP5)3 peptide derived from VASP with an affinity of approximately 0.5 microM. The resulting profilin II-peptide complex overcomes the combined capacity of thymosin beta4 and profilin II to inhibit actin nucleation and restores the extent of filament formation. We do not observe such an effect when barbed filament ends are capped. Neither can profilin I, in the presence of the peptide, promote actin polymerization during its early phase consistent with a lower affinity. Since a Pro17 peptide-profilin II complex only partially restores actin polymerization, the glycine residues in the VASP peptide appear important.
Study Information
pubmed
1999
1999-03-26T00:00:00.000Z
10.1016/s0014-5793(99)00293-8