| SMN2 | |||||||||||||||||||||||||||||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| |||||||||||||||||||||||||||||||||||||||||||||||||||
| Identifiers | |||||||||||||||||||||||||||||||||||||||||||||||||||
| Aliases | SMN2 , BCD541, C-BCD541, GEMIN1, SMNC, TDRD16B, survival of motor neuron 2, centromeric, survival motor neuron 2, centromeric | ||||||||||||||||||||||||||||||||||||||||||||||||||
| External IDs | OMIM: 601627 MGI: 109257 HomoloGene: 292 GeneCards: SMN2 | ||||||||||||||||||||||||||||||||||||||||||||||||||
| |||||||||||||||||||||||||||||||||||||||||||||||||||
| |||||||||||||||||||||||||||||||||||||||||||||||||||
| |||||||||||||||||||||||||||||||||||||||||||||||||||
| |||||||||||||||||||||||||||||||||||||||||||||||||||
| |||||||||||||||||||||||||||||||||||||||||||||||||||
| Wikidata | |||||||||||||||||||||||||||||||||||||||||||||||||||
| |||||||||||||||||||||||||||||||||||||||||||||||||||
Survival of motor neuron 2 (SMN2) is a gene that encodes the SMN protein (full and truncated) in humans. [5] [6]
The SMN2 gene is part of a 500 kb inverted duplication on chromosome 5q13. This duplicated region contains at least four genes and repetitive elements which make it prone to rearrangements and deletions. The repetitiveness and complexity of the sequence have also caused difficulty in determining the organization of this genomic region. The telomeric ( SMN1 ) and centromeric (SMN2) copies of this gene are nearly identical and encode the same protein. The critical sequence difference between the two genes is a single nucleotide in exon 7, which is thought to be an exon splice enhancer. The nucleotide substitution in SMN2 results in around 80-90% of its transcripts to be a truncated, unstable protein of no biological function (Δ7SMN) and only 10-20% of its transcripts being full-length protein (fl-SMN).[ citation needed ]
Note that the nine exons of both the telomeric and centromeric copies are designated historically as exon 1, 2a, 2b, and 3–8. It is thought that gene conversion events may involve the two genes, leading to varying copy numbers of each gene. [6]
While mutations in the telomeric copy are associated with spinal muscular atrophy, mutations in this gene, the centromeric copy, do not lead to disease. This gene may be a modifier of disease caused by mutation in the telomeric copy.[ citation needed ]
Small nuclear RNA (snRNA) is a class of small RNA molecules that are found within the splicing speckles and Cajal bodies of the cell nucleus in eukaryotic cells. The length of an average snRNA is approximately 150 nucleotides. They are transcribed by either RNA polymerase II or RNA polymerase III. Their primary function is in the processing of pre-messenger RNA (hnRNA) in the nucleus. They have also been shown to aid in the regulation of transcription factors or RNA polymerase II, and maintaining the telomeres.
Spinal muscular atrophy (SMA) is a rare neuromuscular disorder that results in the loss of motor neurons and progressive muscle wasting. It is usually diagnosed in infancy or early childhood and if left untreated it is the most common genetic cause of infant death. It may also appear later in life and then have a milder course of the disease. The common feature is progressive weakness of voluntary muscles, with arm, leg and respiratory muscles being affected first. Associated problems may include poor head control, difficulties swallowing, scoliosis, and joint contractures.
Gideon Dreyfuss is an American biochemist, the Isaac Norris Professor of Biochemistry and Biophysics at the University of Pennsylvania School of Medicine, and an investigator of the Howard Hughes Medical Institute. He was elected to the National Academy of Sciences in 2012.
An exonic splicing silencer (ESS) is a short region of an exon and is a cis-regulatory element. A set of 103 hexanucleotides known as FAS-hex3 has been shown to be abundant in ESS regions. ESSs inhibit or silence splicing of the pre-mRNA and contribute to constitutive and alternate splicing. To elicit the silencing effect, ESSs recruit proteins that will negatively affect the core splicing machinery.
Survival of motor neuron or survival motor neuron (SMN) is a protein that in humans is encoded by the SMN1 and SMN2 genes.
Survival of motor neuron 1 (SMN1), also known as component of gems 1 or GEMIN1, is a gene that encodes the SMN protein in humans.
Small nuclear ribonucleoprotein Sm D1 is a protein that in humans is encoded by the SNRPD1 gene.
Transformer-2 protein homolog beta, also known as TRA2B previously known as splicing factor, arginine/serine-rich 10 (SFRS10), is a protein that in humans is encoded by the TRA2B gene.
Small nuclear ribonucleoprotein Sm D2 is a protein that in humans is encoded by the SNRPD2 gene. It belongs to the small nuclear ribonucleoprotein core protein family, and is required for pre-mRNA splicing and small nuclear ribonucleoprotein biogenesis. Alternative splicing occurs at this locus and two transcript variants encoding the same protein have been identified.
Gem-associated protein 2 (GEMIN2), also called survival of motor neuron protein-interacting protein 1 (SIP1), is a protein that in humans is encoded by the GEMIN2 gene.
Probable ATP-dependent RNA helicase DDX20, also known as DEAD-box helicase 20 and gem-associated protein 3 (GEMIN3), is an enzyme that in humans is encoded by the DDX20 gene.
Small nuclear ribonucleoprotein F is a protein that in humans is encoded by the SNRPF gene.
U2 small nuclear ribonucleoprotein B is a protein that in humans is encoded by the SNRPB2 gene.
H/ACA ribonucleoprotein complex subunit 1 is a protein that in humans is encoded by the GAR1 gene.
Baculoviral IAP repeat-containing protein 1 is a protein that in humans is encoded by the NAIP gene.
Heterogeneous nuclear ribonucleoprotein R is a protein that in humans is encoded by the HNRNPR gene.
WRAP53 is a gene implicated in cancer development. The name was coined in 2009 to describe the dual role of this gene, encoding both an antisense RNA that regulates the p53 tumor suppressor and a protein involved in DNA repair, telomere elongation and maintenance of nuclear organelles Cajal bodies.
Neurodegenerative diseases are a heterogeneous group of complex disorders linked by the degeneration of neurons in either the peripheral nervous system or the central nervous system. Their underlying causes are extremely variable and complicated by various genetic and/or environmental factors. These diseases cause progressive deterioration of the neuron resulting in decreased signal transduction and in some cases even neuronal death. Peripheral nervous system diseases may be further categorized by the type of nerve cell affected by the disorder. Effective treatment of these diseases is often prevented by lack of understanding of the underlying molecular and genetic pathology. Epigenetic therapy is being investigated as a method of correcting the expression levels of misregulated genes in neurodegenerative diseases.
Risdiplam, sold under the brand name Evrysdi, is a medication used to treat spinal muscular atrophy (SMA) and the first oral medication approved to treat this disease.
Alberto Kornblihtt is an Argentine molecular biologist who specializes in alternative ribonucleic acid splicing. During his postdoctoral training with Francisco Baralle in Oxford, Kornblihtt documented one of the first cases of alternative splicing, explaining how a single transcribed gene can generate multiple protein variants. Kornblihtt was elected as a foreign associate of the National Academy of Sciences of the United States in 2011, received the Diamond Award for the most relevant scientist of Argentina of the decade, alongside physicist Juan Martin Maldacena, in 2013, and was incorporated to the Académie des Sciences of France in 2022.
PDB gallery | |
|---|---|
|
This article incorporates text from the United States National Library of Medicine, which is in the public domain.
