HP1alpha Antibody – Rabbit

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. [provided by RefSeq, Jul 2008]

HP1 alpha: 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. Interacts with SUV420H1 and SUV420H2. Interacts with HP1BP3. Interacts directly with ATRX, CHAF1A, LBR, NIPBL, SP100, STAM2 and TRIM28 via the chromoshadow domain. Can interact directly with CBX3 via the chromoshadow domain. Interacts with histone H3 methylated at 'Lys- 9'. Interacts with BAHD1, MIS12 and DSN1. Interacts with POGZ; POGZ and PXVXL motif-containing proteins such as INCENP and TRIM28 compete for interaction with CBX5. Interacts with INCENP and TRIM24. Interacts with JC virus agnoprotein; this interaction induces the dissociation of CBX5 from LBR, resulting in destabilization of the nuclear envelope. Interacts with CHAMP1. Interacts with ASXL1.

Protein type: Transcription, coactivator/corepressor

Chromosomal Location of Human Ortholog: 12q13.13

Cellular Component: nucleoplasm; kinetochore; histone methyltransferase complex; PML body; transcriptional repressor complex; histone deacetylase complex; nucleolus; nuclear envelope; nuclear heterochromatin; nucleus; chromocenter

Molecular Function: protein binding, bridging; protein binding; protein homodimerization activity; histone deacetylase binding; chromatin binding; methylated histone residue binding

Biological Process: viral reproduction; blood coagulation; negative regulation of transcription, DNA-dependent