LifeAct
LifeAct is a short peptide used as a fluorescent probe to visualize filamentous actin (F-actin) in living cells. Derived from the actin-binding region of the yeast protein Abp140, the peptide comprises about 17 amino acids. When fused to fluorescent proteins such as GFP or mCherry, LifeAct enables real-time imaging of actin dynamics as LifeAct-GFP or LifeAct-mCherry.
LifeAct binds along the length of F-actin filaments, labeling cortical networks, lamellipodia, filopodia, and stress fibers,
Advantages include its small size, which tends to perturb actin less than larger actin-binding domains and
Variants and controls: Researchers often express LifeAct at low levels, use nonbinding mutants as controls, or
Origin: LifeAct was developed in the late 2000s by Riedl and colleagues as a compact F-actin marker