CBX5

This gene encodes a highly conserved nonhistone protein, which is a member of the heterochromatin protein family. The protein is enriched in the heterochromatin and associated with centromeres. The protein has a single N-terminal chromodomain which can bind to histone proteins via methylated lysine residues, and a C-terminal chromo shadow-domain (CSD) which is responsible for the homodimerization and interaction with a number of chromatin-associated nonhistone proteins. The encoded product is involved in the formation of functional kinetochore through interaction with essential kinetochore proteins. The gene has a pseudogene located on chromosome 3. Multiple alternatively spliced variants, encoding the same protein, have been identified.

Chromobox 5

Chromobox 5; Chromobox Homolog 5 (HP1 Alpha Homolog, Drosophila); Heterochromatin Protein 1 Homolog Alpha; Antigen P25; HP1A; Chromobox Homolog 5 (Drosophila HP1 Alpha); Heterochromatin Protein 1-Alpha; HP1 Alpha Homolog (Drosophila); Epididymis Luminal Protein 25;

Component of heterochromatin that recognizes and binds histone H3 tails methylated at 'Lys-9' (H3K9me), leading to epigenetic repression. In contrast, it is excluded from chromatin when 'Tyr-41' of histone H3 is phosphorylated (H3Y41ph). Can interact with lamin-B receptor (LBR). This interaction can contribute to the association of the heterochromatin with the inner nuclear membrane. Involved in the formation of functional kinetochore through interaction with MIS12 complex proteins.

Blood coagulation Source: Reactome
Cellular response to DNA damage stimulus Source: UniProtKB
Negative regulation of G0 to G1 transition Source: Reactome
Negative regulation of transcription, DNA-templated Source: UniProtKB
Negative regulation of transcription by RNA polymerase II Source: UniProtKB
Viral process Source: UniProtKB-KW

Nucleus; Chromosome; Centromere. Associates with chromatin. Before prophase it is scattered along chromosome arms. During prophase, most of cohesin complexes dissociate from chromatin probably because of phosphorylation by PLK, except at centromeres, where cohesin complexes remain. At anaphase, the RAD21 subunit of the cohesin complex is cleaved, leading to the dissociation of the complex from chromosomes, allowing chromosome separation. The phosphorylated form at Ser-1083 is preferentially associated with unsynapsed chromosomal regions (By similarity).

Phosphorylation of HP1 and LBR may be responsible for some of the alterations in chromatin organization and nuclear structure which occur at various times during the cell cycle (By similarity). Phosphorylated during interphase and possibly hyper-phosphorylated during mitosis.
Ubiquitinated.