Epigenetic restriction of herpes simplex virus occurs in a biphasic manner, in which ATRX maintains viral heterochromatin after an initial phase of chromatin deposition.
Cooperative association of a histone-binding complex with pairs of appropriately modified nucleosomes, which form fundamental units of binding, mediates selective heterochromatin assembly and spreading.
Origin recognition complex-associated (ORCA) is crucial for the stability of the Histone H3 lysine 9 methyltransferase megacomplex, which is essential for heterochromatin organization.
Genetic and biochemical studies show that a conserved ribosome biogenesis complex also localizes to heterochromatin, where it triggers RNA degradation and promotes the spreading and epigenetic inheritance of histone methylation.
Redundant pathways prevent heterochromatin spreading and ectopic heterochromatin assembly; and plasticity of heterochromatin assembly allows cells to adapt to heterochromatin stress.
The histone modification H3K9me2 marks peripheral heterochromatin and ensures positional information is safeguarded through cell division such that individual lamina-associated domains are re-established at the nuclear periphery in daughter nuclei.
Suv39h1 chromodomain possesses nucleic acid-binding activity and this activity is coupled with its H3K9 methylation recognition in assembling heterochromatin.
Genome-wide profiling and functional analyses reveal a network of heterochromatin and small RNA factors that silences repetitive elements and prevents genotoxic stress to ensure fertility.
