| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1177696 | Biochimica et Biophysica Acta (BBA) - Proteins and Proteomics | 2016 | 7 Pages |
•The effect of twinfilin 1 on actin is only partially uncovered.•Twinfilin 1 decreased the accessibility of the nucleotide binding region on actin.•Twinfilin 1 decreased the flexibility of the small domain of actin.•The overall thermodynamic stability of actin increased due to twinfilin 1.•Actin can adapt its conformation to meet the demands of its partner proteins.
The effect of twinfilin-1 on the structure and dynamics of monomeric actin was investigated with fluorescence spectroscopy and differential scanning calorimetry experiments. Fluorescence anisotropy measurements proved that G-actin and twinfilin-1 could form a complex. Due to the formation of the complexes the dissociation of the nucleotide slowed down from the nucleotide-binding pocket of actin. Fluorescence quenching experiments showed that the accessibility of the actin bound ε-ATP decreased in the presence of twinfilin-1. Temperature dependent fluorescence resonance energy transfer and differential scanning calorimetry experiments revealed that the protein matrix of actin becomes more rigid and more heat resistant in the presence of twinfilin-1. The results suggest that the nucleotide binding cleft shifted into a more closed and stable conformational state of actin in the presence of twinfilin-1.
