Centromere protein H is a protein

Protein

Proteins are biochemical compounds consisting of one or more polypeptides typically folded into a globular or fibrous form, facilitating a biological function. A polypeptide is a single linear polymer chain of amino acids bonded together by peptide bonds between the carboxyl and amino groups of...

 that in humans is encoded by the CENPH gene

Gene

A gene is a molecular unit of heredity of a living organism. It is a name given to some stretches of DNA and RNA that code for a type of protein or for an RNA chain that has a function in the organism. Living beings depend on genes, as they specify all proteins and functional RNA chains...

.

Function

Centromere

Centromere

A centromere is a region of DNA typically found near the middle of a chromosome where two identical sister chromatids come closest in contact. It is involved in cell division as the point of mitotic spindle attachment...

 and kinetochore

Kinetochore

The kinetochore is the protein structure on chromatids where the spindle fibers attach during cell division to pull sister chromatids apart....

 proteins play a critical role in centromere structure, kinetochore formation, and sister chromatid

Sister chromatids

Sister chromatids are two identical copies of a chromatid connected by a centromere. Compare sister chromatids to homologous chromosomes, which are the two different copies of the same chromosome that diploid organisms inherit, one from each parent...

 separation. The protein encoded by this gene colocalizes with inner kinetochore plate proteins CENP-A

CENPA

Centromere protein A, also known as CENPA, is a protein which in humans is encoded by the CENPA gene.Centromeres are the differentiated chromosomal domains that specify the mitotic behavior of chromosomes. The CENPA gene encodes a centromere protein which contains a histone H3 related histone fold...

 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

Prometaphase is the phase of mitosis following prophase and preceding metaphase, in eukaryotic somatic cells. In Prometaphase, The nuclear envelope breaks into fragments and disappears. The tiny nucleolus inside the nuclear envolope, also dissolves. Microtubules emerging from the centrosomes at the...

. 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

Coiled coil

A coiled coil is a structural motif in proteins, in which 2-7 alpha-helices are coiled together like the strands of a rope . Many coiled coil type proteins are involved in important biological functions such as the regulation of gene expression e.g. transcription factors...

 structure

Protein structure

Proteins are an important class of biological macromolecules present in all organisms. Proteins are polymers of amino acids. Classified by their physical size, proteins are nanoparticles . Each protein polymer – also known as a polypeptide – consists of a sequence formed from 20 possible L-α-amino...

 and a nuclear

Cell nucleus

In cell biology, the nucleus is a membrane-enclosed organelle found in eukaryotic cells. It contains most of the cell's genetic material, organized as multiple long linear DNA molecules in complex with a large variety of proteins, such as histones, to form chromosomes. The genes within these...

 localisation signal.

Studies show that CENP-H may be associated with certain human cancer

Cancer

Cancer , known medically as a malignant neoplasm, is a large group of different diseases, all involving unregulated cell growth. In cancer, cells divide and grow uncontrollably, forming malignant tumors, and invade nearby parts of the body. The cancer may also spread to more distant parts of the...

s.

CENP-H shows sequence similarity to the Schizosaccharomyces pombe

Schizosaccharomyces pombe

Schizosaccharomyces pombe, also called "fission yeast", is a species of yeast. It is used as a model organism in molecular and cell biology. It is a unicellular eukaryote, whose cells are rod-shaped. Cells typically measure 3 to 4 micrometres in diameter and 7 to 14 micrometres in length...

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

Tandem repeat

Tandem repeats occur in DNA when a pattern of two or more nucleotides is repeated and the repetitions are directly adjacent to each other. -Example:An example would be:in which the sequence A-T-T-C-G is repeated three times.-Terminology:...

 region of the centromere.

Other Protein Interactions

CENPH has also been shown to interact with KIAA0090

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 interacts with multiple effector proteins...

. The significance of this interaction is unclear.

Further reading