NOP56

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What is the official name of the NOP56 gene?

The official name of this gene is “NOP56 ribonucleoprotein.”

NOP56 is the gene's official symbol. The NOP56 gene is also known by other names, listed below.

Read more about gene names and symbols on the About page.

What is the normal function of the NOP56 gene?

The NOP56 gene provides instructions for making a protein called nucleolar protein 56, which is found in the nucleus of nerve cells (neurons). This protein is mostly found in neurons within an area of the brain called the cerebellum, which is involved in coordinating movements. Nucleolar protein 56 is one part (subunit) of the ribonucleoprotein complex, which is composed of proteins and molecules of RNA, DNA's chemical cousin. The ribonucleoprotein complex is needed to make cellular structures called ribosomes, which process the cell's genetic instructions to create proteins.

Located within the NOP56 gene, in an area known as intron 1, is a string of six DNA building blocks (nucleotides); this string, known as a hexanucleotide, is represented by the letters GGCCTG and is typically repeated 3 to 14 times within intron 1. The function of this repeated hexanucleotide is unclear.

How are changes in the NOP56 gene related to health conditions?

spinocerebellar ataxia type 36 - caused by mutations in the NOP56 gene: NOP56 gene mutations cause spinocerebellar ataxia type 36 (SCA36), which is a condition characterized by progressive movement problems that typically begin in mid-adulthood. In people with SCA36, the GGCCTG string in intron 1 is repeated at least 650 times.
To make proteins from the genetic instructions carried in genes, a molecule called messenger RNA (mRNA) is formed. This molecule acts as a genetic blueprint for protein production. However, a large increase in the number of GGCCTG repeats in the NOP56 gene disrupts the normal structure of NOP56 mRNA. Abnormal NOP56 mRNA molecules form clumps called RNA foci within the nucleus of neurons. Other proteins become trapped in the RNA foci, where they cannot function. These proteins may be important for controlling gene activity or protein production.
Additionally, researchers believe that the large expansion of the hexanucleotide repeat in theNOP56 gene may reduce the activity of a nearby gene called MIR1292. The MIR1292 gene provides instructions for making a type of RNA that regulates the activity (expression) of genes that produce proteins called glutamate receptors. These proteins are found on the surface of neurons and allow these cells to communicate with one another. A decrease in the production of Mir1292 RNA can lead to an increase in the production of glutamate receptors. The increased receptor activity may overexcite neurons, which disrupts normal communication between cells and can contribute to movement difficulties.
The combination of RNA foci and overly excited neurons likely leads to the death of neurons over time. Because the NOP56 gene is especially active in neurons in the cerebellum, these cells are particularly affected by expansion of the gene, leading to cell death in the cerebellum. Deterioration in this part of the brain leads to ataxia and the other signs and symptoms of SCA36.

Where is the NOP56 gene located?

Cytogenetic Location: 20p13

Molecular Location on chromosome 20: base pairs 2,652,531 to 2,658,392

The NOP56 gene is located on the short (p) arm of chromosome 20 at position 13.

More precisely, the NOP56 gene is located from base pair 2,652,531 to base pair 2,658,392 on chromosome 20.

See How do geneticists indicate the location of a gene? in the Handbook.

Where can I find additional information about NOP56?

You and your healthcare professional may find the following resources about NOP56 helpful.

Educational resources - Information pages
Madame Curie Bioscience Database: Molecular Mechanisms of TRS Instability
Gene Reviews - Clinical summary
Genetic Testing Registry - Repository of genetic test information (1 link)

You may also be interested in these resources, which are designed for genetics professionals and researchers.

PubMed - Recent literature
OMIM - Genetic disorder catalog
Research Resources - Tools for researchers (3 links)

What other names do people use for the NOP56 gene or gene products?

NOL5A
NOP56 ribonucleoprotein homolog
nucleolar protein 5A (56kDa with KKE/D repeat)
nucleolar protein 56

See How are genetic conditions and genes named? in the Handbook.

Where can I find general information about genes?

The Handbook provides basic information about genetics in clear language.

These links provide additional genetics resources that may be useful.

What glossary definitions help with understanding NOP56?

ataxia ; cell ; cerebellum ; DNA ; gene ; intron ; messenger RNA ; molecule ; mRNA ; nucleus ;protein ; receptor ; ribosomes ; RNA ; subunit

You may find definitions for these and many other terms in the Genetics Home Reference Glossary.

References (6 links)

The resources on this site should not be used as a substitute for professional medical care or advice. Users seeking information about a personal genetic disease, syndrome, or condition should consult with a qualified healthcare professional. See How can I find a genetics professional in my area? in the Handbook.