Submitted by Zuzana Keckesova in the Weinberg Laboratory at the Whitehead Institute
"This image depicts the beginning stage of skeletal muscle differentiation. Cells are starting to fuse together (mostly two nuclei per cell at this stage) and starting to express the myogenic differentiation marker alpha-actinin (white). Nuclei stained with DAPI (blue). This image showed successful in vitro skeletal muscle differentiation protocol."