 The researchers examined the role of histone variants and histone modifications in the organization of chromatin states in Arabidopsis taliana. They found that histone variants are as important as histone modifications in determining the composition of chromatin states. In particular, they observed strong associations between H2A variants and specific combinations of histone modifications. The researchers also studied the role of the chromatin remodular decreased in DNA methylation, DDM1, in the organization of chromatin states. They found that the loss of DDM1 prevented the exchange of the histone variant H2A.z to H2A.w in constitutive heterochromatin, resulting in significant effects on the definition and distribution of chromatin states in and outside of constitutive heterochromatin. Based on their findings, the researchers proposed that dynamic exchanges of histone variants control the organization of histone modifications into chromatin states, acting as molecular landmarks. This article was authored by Bagishri Jamj, Stravo J. Lokovic, Ily Axelson, and others. We are article.tv, links in the description below.