CBX5 belongs to the heterochromatin protein family. CBX5 is enriched in the heterochromatin and linked with centromeres. CBX5 takes part in the creation of functional kinetochore by interaction with important kinetochore proteins. CBX5 has a pseudogene situated on chromosome 3. Additionaly, The CBX5 proteins reconnect with chromatin at the end of mitosis, as Histone H3 is dephosphorylated.