Submitted Successfully!
To reward your contribution, here is a gift for you: A free trial for our video production service.
Thank you for your contribution! You can also upload a video entry or images related to this topic.
Version Summary Created by Modification Content Size Created at Operation
1 + 434 word(s) 434 2020-12-15 08:05:38

Video Upload Options

Do you have a full video?

Confirm

Are you sure to Delete?
Cite
If you have any further questions, please contact Encyclopedia Editorial Office.
Guo, L. POLR3B Gene. Encyclopedia. Available online: https://encyclopedia.pub/entry/5790 (accessed on 29 March 2024).
Guo L. POLR3B Gene. Encyclopedia. Available at: https://encyclopedia.pub/entry/5790. Accessed March 29, 2024.
Guo, Lily. "POLR3B Gene" Encyclopedia, https://encyclopedia.pub/entry/5790 (accessed March 29, 2024).
Guo, L. (2020, December 25). POLR3B Gene. In Encyclopedia. https://encyclopedia.pub/entry/5790
Guo, Lily. "POLR3B Gene." Encyclopedia. Web. 25 December, 2020.
POLR3B Gene
Edit

RNA polymerase III subunit B

genes

1. Introduction

The POLR3B gene provides instructions for making one part (subunit) of an enzyme called RNA polymerase III. This enzyme is involved in the production (synthesis) of ribonucleic acid (RNA), a chemical cousin of DNA. The RNA polymerase III enzyme attaches (binds) to DNA and synthesizes RNA in accordance with the instructions carried by the DNA, a process called transcription. RNA polymerase III helps synthesize several forms of RNA, including ribosomal RNA (rRNA) and transfer RNA (tRNA). Molecules of rRNA and tRNA assemble protein building blocks (amino acids) into working proteins; this process is essential for the normal functioning and survival of cells.

2. Health Conditions Related to Genetic Changes

2.1. Pol III-related leukodystrophy

At least 54 POLR3B gene mutations have been associated with Pol III-related leukodystrophy. Leukodystrophies are conditions that involve abnormalities of the nervous system's white matter. White matter consists of nerve fibers covered by a fatty substance called myelin, which insulates nerve fibers and promotes the rapid transmission of nerve impulses. A reduced ability to form myelin (hypomyelination) leads to the signs and symptoms of Pol III-related leukodystrophy, which include intellectual disability and difficulty with coordinating movements (ataxia). Development of the teeth (dentition) is also abnormal in this disorder.

In the Pol III-related leukodystrophies, POLR3B gene mutations may impair the ability of the subunits of the RNA polymerase III enzyme to assemble properly or result in an RNA polymerase III with impaired ability to bind to DNA. Reduced function of the RNA polymerase III molecule likely affects development and function of many parts of the body, but the relationship between POLR3B gene mutations and the specific signs and symptoms of these disorders is unknown.

People with Pol III-related leukodystrophy may have different combinations of its signs and symptoms. These varied combinations of clinical features were originally described as separate disorders. Affected individuals may be diagnosed with ataxia, delayed dentition, and hypomyelination (ADDH); hypomyelination, hypodontia, hypogonadotropic hypogonadism (4H syndrome); tremor-ataxia with central hypomyelination (TACH); leukodystrophy with oligodontia (LO); or hypomyelination with cerebellar atrophy and hypoplasia of the corpus callosum (HCAHC). Because these disorders were later found to have the same genetic cause, researchers now group them as variations of the single condition Pol III-related leukodystrophy.

3. Other Names for This Gene

  • C128
  • DNA-directed RNA polymerase III 127.6 kDa polypeptide
  • DNA-directed RNA polymerase III subunit B
  • DNA-directed RNA polymerase III subunit RPC2
  • DNA-directed RNA polymerase III subunit RPC2 isoform 1
  • DNA-directed RNA polymerase III subunit RPC2 isoform 2
  • FLJ10388
  • HLD8
  • polymerase (RNA) III (DNA directed) polypeptide B
  • polymerase (RNA) III subunit B
  • RNA polymerase III subunit C2
  • RPC2
  • RPC2_HUMAN

References

  1. Daoud H, Tétreault M, Gibson W, Guerrero K, Cohen A, Gburek-Augustat J,Synofzik M, Brais B, Stevens CA, Sanchez-Carpintero R, Goizet C, Naidu S,Vanderver A, Bernard G. Mutations in POLR3A and POLR3B are a major cause ofhypomyelinating leukodystrophies with or without dental abnormalities and/orhypogonadotropic hypogonadism. J Med Genet. 2013 Mar;50(3):194-7. doi:10.1136/jmedgenet-2012-101357.
  2. Saitsu H, Osaka H, Sasaki M, Takanashi J, Hamada K, Yamashita A, Shibayama H, Shiina M, Kondo Y, Nishiyama K, Tsurusaki Y, Miyake N, Doi H, Ogata K, Inoue K,Matsumoto N. Mutations in POLR3A and POLR3B encoding RNA Polymerase III subunits cause an autosomal-recessive hypomyelinating leukoencephalopathy. Am J Hum Genet.2011 Nov 11;89(5):644-51. doi: 10.1016/j.ajhg.2011.10.003.
  3. Tétreault M, Choquet K, Orcesi S, Tonduti D, Balottin U, Teichmann M, FribourgS, Schiffmann R, Brais B, Vanderver A, Bernard G. Recessive mutations in POLR3B, encoding the second largest subunit of Pol III, cause a rare hypomyelinatingleukodystrophy. Am J Hum Genet. 2011 Nov 11;89(5):652-5. doi:10.1016/j.ajhg.2011.10.006.
  4. Vanderver A, Tonduti D, Bernard G, Lai J, Rossi C, Carosso G, Quezado M, Wong K, Schiffmann R. More than hypomyelination in Pol-III disorder. J Neuropathol ExpNeurol. 2013 Jan;72(1):67-75. doi: 10.1097/NEN.0b013e31827c99d2.
More
Information
Contributor MDPI registered users' name will be linked to their SciProfiles pages. To register with us, please refer to https://encyclopedia.pub/register :
View Times: 298
Entry Collection: MedlinePlus
Revision: 1 time (View History)
Update Date: 25 Dec 2020
1000/1000