CENPA

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CENPA
Protein CENPA PDB 3NQJ.png
Available structures
PDB Ortholog search: PDBe RCSB
Identifiers
Aliases CENPA, CENP-A, CenH3, centromere protein A
External IDs MGI: 88375 HomoloGene: 1369 GeneCards: 1058
Orthologs
Species Human Mouse
Entrez
Ensembl
UniProt
RefSeq (mRNA)

NM_001809
NM_001042426

NM_007681
NM_001302129
NM_001302130
NM_001302131
NM_001302132

RefSeq (protein)

NP_001035891.1
NP_001800.1

NP_001289058.1
NP_001289059.1
NP_001289060.1
NP_001289061.1
NP_031707.1

Location (UCSC) Chr 2: 26.76 – 26.8 Mb Chr 5: 30.67 – 30.67 Mb
PubMed search [1] [2]
Wikidata
View/Edit Human View/Edit Mouse

Centromere protein A, also known as CENPA, is a protein which in humans is encoded by the CENPA gene.[3]

Function[edit]

Centromeres are the chromosomal domains that specify the mitotic behavior of chromosomes. The CENPA gene encodes a centromere protein which contains a histone H3 related histone fold domain that is required for targeting to the centromere. CENPA is proposed to be a component of a modified nucleosome or nucleosome-like structure in which it replaces 1 or both copies of conventional histone H3 in the (H3-H4)2 tetrameric core of the nucleosome particle. Alternative splicing results in multiple transcript variants encoding distinct isoforms.[3]

In higher eukaryotes, the recruitment of CENP-A nucleosomes to existing centromeres is an epigenetic process, independent of the underlying DNA sequence. In S.pombe, de novo recruitment of the CENP-A to the centromere is believed to be controlled by "centromeric" heterochromatin surrounding the centromere, and by an RNAi mechanism. The RNAi is cut to form siRNA; this complexes with the protein Chp1, which then binds the centromeric heterochromatin. This helps recruit other proteins, ultimately resulting in a protein complex that forms cohesin between two sister chromatids at the centromeric heterochromatin. This cohesin is believed to be essential in replacing the centromere H3 with CENP-A. CENP-A is one of the epigenetic changes that is believed to distinguish centromeric DNA from other DNA.[4] Once the CENP-A has been added, the centromere becomes self-propagating, and the surrounding heterochromatin/RNAi mechanism is no longer necessary.[5]

References[edit]

  1. ^ "Human PubMed Reference:". 
  2. ^ "Mouse PubMed Reference:". 
  3. ^ a b EntrezGene 1058
  4. ^ Chueh AC, Wong LH, Wong N, Choo KH (January 2005). "Variable and hierarchical size distribution of L1-retroelement-enriched CENP-A clusters within a functional human neocentromere". Hum. Mol. Genet. 14 (1): 85–93. doi:10.1093/hmg/ddi008. PMID 15537667. 
  5. ^ Folco HD, Pidoux AL, Urano T, Allshire RC (January 2008). "Heterochromatin and RNAi are required to establish CENP-A chromatin at centromeres". Science. 319 (5859): 94–7. doi:10.1126/science.1150944. PMC 2586718free to read. PMID 18174443. 

Further reading[edit]