HuGE, a novel GFP-actin-expressing mouse line for studying cytoskeletal dynamics.

Analysis of actin remodeling in live cells and tissues has become an increasingly important tool to study actin-dependent cellular processes. To facilitate these experiments in the mouse we have generated a GFP-actin-expressing line (huGE) by knock-in of the GFP-actin gene into the profilin 1 locus. Here we show that GFP-actin is expressed throughout embryonic development and in all tissues except skeletal muscle, in a pattern similar to profilin 1. Particularly high expression of GFP-actin was observed in bone marrow and all blood cells. The GFP-actin fusion protein is functional as shown by its co-localization with endogenous actin in F-actin-rich structures. Therefore, the huGE mouse line provides a novel tool to monitor actin dynamics in mouse embryos and a wide range of organs.