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66  structures 922  species 0  interactions 1081  sequences 16  architectures

Family: CENP-X (PF09415)

Summary: CENP-S associating Centromere protein X

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CENP-S associating Centromere protein X Provide feedback

The centromere, essential for faithful chromosome segregation during mitosis, has a network of constitutive centromere-associated (CCAN) proteins associating with it during mitosis. So far in vertebrates at least 15 centromere proteins have been identified, which are divided into several subclasses based on functional and biochemical analyses. These provide a platform for the formation of a functional kinetochore during mitosis. CENP-S is one that does not associate with the CENP-H-containing complex but rather interacts with CENP-X to form a stable assembly of outer kinetochore proteins that functions downstream of other components of the CCAN. This complex may directly allow efficient and stable formation of the outer kinetochore on the CCAN platform.

Literature references

  1. Amano M, Suzuki A, Hori T, Backer C, Okawa K, Cheeseman IM, Fukagawa T;, J Cell Biol. 2009;186:173-182.: The CENP-S complex is essential for the stable assembly of outer kinetochore structure. PUBMED:19620631 EPMC:19620631

Internal database links

This tab holds annotation information from the InterPro database.

InterPro entry IPR018552

Centromere protein X (CENP-X) is a component of several different complexes, including the multisubunit FA complex, the heterotetrameric CENP-T-W-S-X complex and the APITD1/CENPS complex.

The Fanconi anemia (FA) core complex is involved in DNA damage repair and genome maintenance. The FA complex is composed of CENPS, FANCA, FANCB, FANCC, FANCE, FANCF, FANCG, FANCL/PHF9, FANCM, FAAP24 and CENPX. Interacts with CENPS, FANCM and FAAP24 [ PUBMED:20347428 , PUBMED:20347429 ]. Inner kinetochore subunit mhf2 is the dsDNA-binding component of the FANCM-MHF complex, important for gene conversion at blocked replication forks [ PUBMED:20347428 ] and non-crossover recombination during mitosis and meiosis [ PUBMED:22723423 ].

The CENP-T-W-S-X complex binds, supercoils DNA and plays an important role in kinetochore assembly [ PUBMED:22304917 ].

The APITD1/CENPS complex is composed of at least of CENP-S and CENP-X and is essential for the stable assembly of the outer kinetchore [ PUBMED:19620631 ].

Gene Ontology

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Domain organisation

Below is a listing of the unique domain organisations or architectures in which this domain is found. More...

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Pfam Clan

This family is a member of clan Histone (CL0012), which has the following description:

Members of this clan all possess a histone fold. Generally proteins in this clan are DNA binding.

The clan contains the following 17 members:



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Curation and family details

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Curation View help on the curation process

Seed source: manual
Previous IDs: DUF2008;
Type: Domain
Sequence Ontology: SO:0000417
Author: Mistry J , Wood V
Number in seed: 81
Number in full: 1081
Average length of the domain: 70.10 aa
Average identity of full alignment: 36 %
Average coverage of the sequence by the domain: 48.24 %

HMM information View help on HMM parameters

HMM build commands:
build method: hmmbuild -o /dev/null HMM SEED
search method: hmmsearch -Z 61295632 -E 1000 --cpu 4 HMM pfamseq
Model details:
Parameter Sequence Domain
Gathering cut-off 25.0 25.0
Trusted cut-off 25.1 25.0
Noise cut-off 24.8 24.9
Model length: 75
Family (HMM) version: 13
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Species distribution

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Archea Archea Eukaryota Eukaryota
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For those sequences which have a structure in the Protein DataBank, we use the mapping between UniProt, PDB and Pfam coordinate systems from the PDBe group, to allow us to map Pfam domains onto UniProt sequences and three-dimensional protein structures. The table below shows the structures on which the CENP-X domain has been found. There are 66 instances of this domain found in the PDB. Note that there may be multiple copies of the domain in a single PDB structure, since many structures contain multiple copies of the same protein sequence.

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