Lifeact: a versatile marker to visualize F-actin

Current approaches for live imaging of cellular actin dynamics have several drawbacks. Now the use of Lifeact, a 17-aa actin-binding peptide from yeast that is not present in higher eukaryotes, allows imaging of actin dynamics in live mammalian cells without disruption of function and without competition with endogenous binding proteins. Live imaging of the actin cytoskeleton is crucial for the study of many fundamental biological processes, but current approaches to visualize actin have several limitations. Here we describe Lifeact, a 17-amino-acid peptide, which stained filamentous actin (F-actin) structures in eukaryotic cells and tissues. Lifeact did not interfere with actin dynamics in vitro and in vivo and in its chemically modified peptide form allowed visualization of actin dynamics in nontransfectable cells.