In mammalian dosage compensation, one X chromosome in expresses the lncRNA, which spreads along the X chromosome and recruits proteins that add the chromatin mark. As a consequence, the chromosome consists mostly of and expression of genes on that X chromosome isfemale

male

heterochromatin

dosage compensation complex

roX

Xist

H4K16ac

H3K9me3

unregulated

silenced

H3K9me3.

Explanation:

H3K9me3 is an epigenetic modification to the DNA packaging protein Histone H3. It is a mark that indicates the tri-methylation at the 9th lysine residue of the histone H3 protein and is often associated with heterochromatin.

Chromatin Immunoprecipitation Sequencing (ChIP-sequencing) measures the amount of DNA enrichment once bound to a targeted protein and immunoprecipitated. It results in good optimization and is used in vivo to reveal DNA-protein binding occurring in cells. ChIP-Seq can be used to identify and quantify various DNA fragments for different histone modifications along a genomic region.

H3k9me3

The chromosome will consists mostly of an expression of genes on that X chromosome as H3k9me3.