title: The effect of mouse twinfilin-1 on the structure and dynamics of monomeric actin.
abstract: 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.
authors.affiliation: University of Pécs, Medical School, Department of Biophysics, Pécs, Szigeti Str. 12, H-7624, Hungary.
authors.forename: Veronika
authors.initials: V
authors.lastname: Takács-Kollár
authors.affiliation: University of Pécs, Medical School, Department of Biophysics, Pécs, Szigeti Str. 12, H-7624, Hungary; Szentágothai Research Center, Pécs, Ifjúság Str. 34, H-7624, Hungary; MTA-PTE Nuclear-Mitochondrial Interactions Research Group, Pécs, Szigeti Str. 12, H-7624, Hungary.
authors.forename: Miklós
authors.initials: M
authors.lastname: Nyitrai
authors.affiliation: University of Pécs, Medical School, Department of Biophysics, Pécs, Szigeti Str. 12, H-7624, Hungary; University of Pécs, Medical School, Department of Radiology, Pécs, Ifjúság Str. 13. H-7624, Hungary. Electronic address: gabor.hild@aok.pte.hu.
authors.forename: Gábor
authors.initials: G
authors.lastname: Hild
mesh_terms: D000199:Actins / Q000737:chemistry*; D000818:Animals; D004985:Ethenoadenosine Triphosphate / Q000378:metabolism; D031541:Fluorescence Resonance Energy Transfer; D051379:Mice; D008840:Microfilament Proteins / Q000378:metabolism*; D013050:Spectrometry, Fluorescence; D013696:Temperature
chemical_list: D000199:Actins; D004985:Ethenoadenosine Triphosphate; D008840:Microfilament Proteins; C485190:Twf1 protein, mouse
keywords: Actin; Differential scanning calorimetry; Fluorescence spectroscopy; Mouse twinfilin-1