Profilin promotes barbed-end actin filament assembly without lowering the critical concentration
F Kang, DL Purich, FS Southwick - Journal of Biological Chemistry, 1999 - ASBMB
The mechanism of profilin-promoted actin polymerization has been systematically
reinvestigated. Rates of barbed-end elongation onto Spectrin· 4.1· Actin seeds were
measured by right angle light scattering to avoid confounding effects of pyrenyl-actin, and
KINSIM was used to analyze elongation progress curves. Without thymosin-β4, both actin
and Profilin· Actin (P· A) are competent in barbed-end polymerization, and kinetic
simulations yielded the same bimolecular rate constant (∼ 10× 10 6 m− 1 s− 1) for actin …
reinvestigated. Rates of barbed-end elongation onto Spectrin· 4.1· Actin seeds were
measured by right angle light scattering to avoid confounding effects of pyrenyl-actin, and
KINSIM was used to analyze elongation progress curves. Without thymosin-β4, both actin
and Profilin· Actin (P· A) are competent in barbed-end polymerization, and kinetic
simulations yielded the same bimolecular rate constant (∼ 10× 10 6 m− 1 s− 1) for actin …
