Snoop-LMM SMM cofilaments are stable and can be labeled with SnoopC-QDs. TIRF microscopy images of various rhodamine labeled SMM filament preparations in filament buffer. Scale bar, 5 µm. (A) Control 20 µg ml⁻¹ SMM filaments on a glass coverslip. Arrows indicate aggregates of filaments; carrots indicate single filaments. (B) Overlaid image of 20 µg ml⁻¹ 95% SMM 5% Snoop-LMM cofilaments (red) reacted at 1 µM with 0.12 µM 585 nm QD-SnoopC overnight at 4°C. (C) Same as B, except with 0.12 µM 655 nm QD-SnoopC. For B and C, arrows point to colocalized filaments and QDs.