Spada F, Chioda M, Thompson EM.

J Cell Biochem. 2005 Aug 1;95(5):885-901. doi:10.1002/jcb.20416

Histone H4 post-translational modifications in chordate mitotic and endoreduplicative cell cycles.

Knobs are also seem to be in H4K20me2. In endocycling cells, H4K20me2 tends to be stronger in BrdU-negative (short pulse) cells. CldU/IdU staining confirms that H4K20me2 decreases during the S phase of endocycling cells. In mitotically cycling cells, BrdU-low cells tended to be H4K20me2-weak. Strong H3S28p and H3S10p staining (M phase markers) correlated with strong H4K20me2 staining. In NIH3T3 cells, H4K20me2 peaks at M phase and then decreases from G1 to G2. H4K16Ac stainings were not reproducible across antibodies.