Wh. Goldmann et al., VISCOELASTICITY OF ACTIN-GELSOLIN NETWORKS IN THE PRESENCE OF FILAMIN, European journal of biochemistry, 246(2), 1997, pp. 373-379
Cross-linking of actin filaments by filamin by means of frequency-depe
ndent rheology yields an increase in the filament's elasticity and sti
ffness. Higher cross-linker (filamin) ratios are required for mean act
in-filament lengths of 5-6 mu m than for random-length distribution of
actin filaments. The loss modulus (i.e. the viscous portion) in the r
egion of the internal-chain dynamics [G''(omega) approximate to omega(
alpha)] is influenced by the cross-linking of filaments, and with an i
ncreasing molar ratio of filamin/actin a reduction of a is observed. R
heological measurements reveal that actin networks are already formed
at the polymerizing stage at a molar ratio of filamin/actin of less th
an 1:100, and electron micrographs show phase separation of actin/fila
ment networks of low density and of actin/filament bundles.