SMN2

SMN2
Available structures
PDBOrtholog search: PDBe RCSB
Identifiers
Aliases SMN2, BCD541, C-BCD541, GEMIN1, SMNC, TDRD16B, survival of motor neuron 2, centromeric
External IDs MGI: 109257 HomoloGene: 292 GeneCards: SMN2
Orthologs
Species Human Mouse
Entrez

6607

20595

Ensembl

n/a

ENSMUSG00000021645

UniProt

Q16637

Q16637
P97801

RefSeq (mRNA)

NM_017411
NM_022875
NM_022876
NM_022877

NM_001252629
NM_011420

RefSeq (protein)
Location (UCSC) Chr 5: 70.05 – 70.08 Mb Chr 13: 100.12 – 100.14 Mb
PubMed search [1] [2]
Wikidata
View/Edit HumanView/Edit Mouse

Survival of motor neuron 2, centromeric, also known as SMN2, is a protein which in humans is encoded by the SMN2 gene.[3][4]

Gene

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.

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.[4]

Clinical significance

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.

Function

The full-length SMN protein encoded by this gene, accounting for approximately 10-20% of its total transcripts, localizes to both the cytoplasm and the nucleus. Within the nucleus, the protein localizes to subnuclear bodies called gems which are found near coiled bodies containing high concentrations of small ribonucleoproteins (snRNPs). This protein forms heteromeric complexes with proteins such as SIP1 and GEMIN4, and also interacts with several proteins known to be involved in the biogenesis of snRNPs, such as hnRNP U protein and the small nucleolar RNA binding protein. Four transcript variants encoding distinct isoforms have been described.[4]

References

  1. "Human PubMed Reference:".
  2. "Mouse PubMed Reference:".
  3. Lefebvre S, Bürglen L, Reboullet S, Clermont O, Burlet P, Viollet L, Benichou B, Cruaud C, Millasseau P, Zeviani M (January 1995). "Identification and characterization of a spinal muscular atrophy-determining gene". Cell. 80 (1): 155–65. doi:10.1016/0092-8674(95)90460-3. PMID 7813012.
  4. 1 2 3 "Entrez Gene: survival of motor neuron 2, centromeric".

Further reading

This article incorporates text from the United States National Library of Medicine, which is in the public domain.

This article is issued from Wikipedia - version of the 11/9/2016. The text is available under the Creative Commons Attribution/Share Alike but additional terms may apply for the media files.