Centromere protein H is a
protein
Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residue (biochemistry), residues. Proteins perform a vast array of functions within organisms, including Enzyme catalysis, catalysing metab ...
that in humans is encoded by the ''CENPH''
gene
In biology, the word gene has two meanings. The Mendelian gene is a basic unit of heredity. The molecular gene is a sequence of nucleotides in DNA that is transcribed to produce a functional RNA. There are two types of molecular genes: protei ...
.
It is involved in the assembly of kinetochore proteins, mitotic progression and chromosome segregation.
Function
Centromere
The centromere links a pair of sister chromatids together during cell division. This constricted region of chromosome connects the sister chromatids, creating a short arm (p) and a long arm (q) on the chromatids. During mitosis, spindle fiber ...
and
kinetochore
A kinetochore (, ) is a flared oblique-shaped protein structure associated with duplicated chromatids in eukaryotic cells where the spindle fibers, which can be thought of as the ropes pulling chromosomes apart, attach during cell division to ...
proteins play a critical role in centromere structure, kinetochore formation, and
sister chromatid
A sister chromatid refers to the identical copies ( chromatids) formed by the DNA replication of a chromosome, with both copies joined together by a common centromere. In other words, a sister chromatid may also be said to be 'one-half' of the du ...
separation. The protein encoded by this gene colocalizes with inner kinetochore plate proteins
CENP-A and
CENP-C in both interphase and metaphase. CENP-H is required for the localisation of CENP-C, but not CENP-A, to the centromere. However, it may be involved in the incorporation of newly synthesised CENP-A into centromeres via its interaction with the CENP-A/CENP-HI complex.
CENP-H localizes outside of centromeric heterochromatin, where
CENP-B is localized, and inside the kinetochore corona, where
CENP-E is localized during
prometaphase
Prometaphase is the phase of mitosis following prophase and preceding metaphase in eukaryotic somatic cells. In prometaphase, the nuclear membrane breaks apart into numerous "membrane vesicles," and the chromosomes inside form protein structure ...
. It is thought that this protein can bind to itself, as well as to CENP-A, CENP-B or CENP-C. Multimers of the protein localize constitutively to the inner kinetochore plate and play an important role in the organization and function of the active centromere-kinetochore complex.
CENP-H contains a
coiled-coil
A coiled coil is a structural motif in proteins in which two to seven alpha-helices are coiled together like the strands of a rope. ( Dimers and trimers are the most common types.) They have been found in roughly 5-10% of proteins and have a v ...
structure
A structure is an arrangement and organization of interrelated elements in a material object or system, or the object or system so organized. Material structures include man-made objects such as buildings and machines and natural objects such as ...
and a
nuclear
Nuclear may refer to:
Physics
Relating to the nucleus of the atom:
*Nuclear engineering
*Nuclear physics
*Nuclear power
*Nuclear reactor
*Nuclear weapon
*Nuclear medicine
*Radiation therapy
*Nuclear warfare
Mathematics
* Nuclear space
*Nuclear ...
localisation signal.
Studies show that CENP-H may be associated with certain
human
Humans (''Homo sapiens'') or modern humans are the most common and widespread species of primate, and the last surviving species of the genus ''Homo''. They are Hominidae, great apes characterized by their Prehistory of nakedness and clothing ...
cancer
Cancer is a group of diseases involving Cell growth#Disorders, abnormal cell growth with the potential to Invasion (cancer), invade or Metastasis, spread to other parts of the body. These contrast with benign tumors, which do not spread. Po ...
s.
CENP-H shows
sequence
In mathematics, a sequence is an enumerated collection of objects in which repetitions are allowed and order matters. Like a set, it contains members (also called ''elements'', or ''terms''). The number of elements (possibly infinite) is cal ...
similarity to the ''
Schizosaccharomyces pombe
''Schizosaccharomyces pombe'', also called "fission yeast", is a species of yeast used in traditional brewing and as a model organism in molecular and cell biology. It is a unicellular eukaryote, whose cells are rod-shaped. Cells typically meas ...
'' kinetochore protein Fta3 which is a subunit of the Sim4 complex. This complex is required for loading the DASH complex onto the kinetochore via interaction with dad1. Fta2, Fta3 and Fta4 associate with the central core and inner
repeat
Repeat may refer to:
* Rerun, a rebroadcast of an episode of a radio or television program
* Repeated sequence (DNA), a pattern of nucleic acid (DNA or RNA) that occurs in multiple copies throughout the genome
** CRISPR
* The smallest rectangle th ...
region of the centromere.
Interactions
CENPH has also been shown to interact with
KIAA0090 KIAA0090 is a human gene coding for a protein of unknown function. KIAA0090 has two aliases OTTHUMP00000002581 and RP1-43E13.1. The gene codes for multiple transcript variants which can localize to different subcellular compartments. KIAA0090 intera ...
.
The significance of this interaction is unclear.
References
External links
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Further reading
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{{InterPro content, IPR008426
Protein domains