The zigzag appearance of nucleosomes in the presence of histone H1. Electron micrographs of nucleosomes (a) in the presence of H1 and (b) in the absence of H1. Histone H1 increases the zigzag appearance by decreasing the DNA entry/exit angles, as shown in the cartoon models to the right of each micrograph. In these electron micrographs, the samples were stained by rotary shadowing using carbon-