OPA1
Identifiers
AliasesOPA1, MGM1, NPG, NTG, largeG, Optic atrophy 1, BERHS, MTDPS14, mitochondrial dynamin like GTPase, OPA1 mitochondrial dynamin like GTPase
External IDsOMIM: 605290 MGI: 1921393 HomoloGene: 14618 GeneCards: OPA1
Orthologs
SpeciesHumanMouse
Entrez
Ensembl
UniProt
RefSeq (mRNA)

NM_001199177
NM_133752

RefSeq (protein)
Location (UCSC)Chr 3: 193.59 – 193.7 MbChr 16: 29.4 – 29.47 Mb
PubMed search[3][4]
Wikidata
View/Edit HumanView/Edit Mouse

Dynamin-like 120 kDa protein, mitochondrial is a protein that in humans is encoded by the OPA1 gene.[5][6] This protein regulates mitochondrial fusion and cristae structure in the inner mitochondrial membrane (IMM) and contributes to ATP synthesis and apoptosis,[7][8][9] and small, round mitochondria.[10] Mutations in this gene have been implicated in dominant optic atrophy (DOA), leading to loss in vision, hearing, muscle contraction, and related dysfunctions.[6][7][11]

Structure

Eight transcript variants encoding different isoforms, resulting from alternative splicing of exon 4 and two novel exons named 4b and 5b, have been reported for this gene.[6] They fall under two types of isoforms: long isoforms (L-OPA1), which attach to the IMM, and short isoforms (S-OPA1), which localize to the intermembrane space (IMS) near the outer mitochondrial membrane (OMM).[12] S-OPA1 is formed by proteolysis of L-OPA1 at the cleavage sites S1 and S2, removing the transmembrane domain.[9]

Function

This gene product is a nuclear-encoded mitochondrial protein with similarity to dynamin-related GTPases. It is a component of the mitochondrial network.[6] The OPA1 protein localizes to the inner mitochondrial membrane, where it regulates mitochondrial fusion and cristae structure.[7] OPA1 mediates mitochondrial fusion in cooperation with mitofusins 1 and 2 and participates in cristae remodeling by the oligomerization of two L-OPA1 and one S-OPA1, which then interact with other protein complexes to alter cristae structure.[8][13] Its cristae regulating function also contributes to its role in oxidative phosphorylation and apoptosis, as it is required to maintain mitochondrial activity during low-energy substrate availability.[7][8][9] Moreover, stabilization of mitochondrial cristae by OPA1 protects against mitochondrial dysfunction, cytochrome c release, and reactive oxygen species production, thus preventing cell death.[14] Mitochondrial SLC25A transporters can detect these low levels and stimulate OPA1 oligomerization, leading to tightening of the cristae, enhanced assembly of ATP synthase, and increased ATP production.[8] Stress from an apoptotic response can interfere with OPA1 oligomerization and prevent mitochondrial fusion.[9]

Clinical significance

Mutations in this gene have been associated with optic atrophy type 1, which is a dominantly inherited optic neuropathy resulting in progressive loss of visual acuity, leading in many cases to legal blindness.[6] Dominant optic atrophy (DOA) in particular has been traced to mutations in the GTPase domain of OPA1, leading to sensorineural hearing loss, ataxia, sensorimotor neuropathy, progressive external ophthalmoplegia, and mitochondrial myopathy.[7][11] As the mutations can lead to degeneration of auditory nerve fibres, cochlear implants provide a therapeutic means to improve hearing thresholds and speech perception in patients with OPA1-derived hearing loss.[7]

Mitochondrial fusion involving OPA1 and MFN2 may be associated with Parkinson's disease.[11]

Interactions

OPA1 has been shown to interact with:

See also

References

  1. ^ a b c GRCh38: Ensembl release 89: ENSG00000198836 - Ensembl, May 2017
  2. ^ a b c GRCm38: Ensembl release 89: ENSMUSG00000038084 - Ensembl, May 2017
  3. ^ "Human PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.
  4. ^ "Mouse PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.
  5. ^ Votruba M, Moore AT, Bhattacharya SS (Jan 1998). "Demonstration of a founder effect and fine mapping of dominant optic atrophy locus on 3q28-qter by linkage disequilibrium method: a study of 38 British Isles pedigrees". Human Genetics. 102 (1): 79–86. doi:10.1007/s004390050657. PMID 9490303. S2CID 26060748.
  6. ^ a b c d e "Entrez Gene: OPA1 optic atrophy 1 (autosomal dominant)".
  7. ^ a b c d e f Santarelli R, Rossi R, Scimemi P, Cama E, Valentino ML, La Morgia C, Caporali L, Liguori R, Magnavita V, Monteleone A, Biscaro A, Arslan E, Carelli V (Mar 2015). "OPA1-related auditory neuropathy: site of lesion and outcome of cochlear implantation". Brain. 138 (Pt 3): 563–76. doi:10.1093/brain/awu378. PMC 4339771. PMID 25564500.
  8. ^ a b c d e f g h i j k Patten DA, Wong J, Khacho M, Soubannier V, Mailloux RJ, Pilon-Larose K, MacLaurin JG, Park DS, McBride HM, Trinkle-Mulcahy L, Harper ME, Germain M, Slack RS (Nov 2014). "OPA1-dependent cristae modulation is essential for cellular adaptation to metabolic demand". The EMBO Journal. 33 (22): 2676–91. doi:10.15252/embj.201488349. PMC 4282575. PMID 25298396.
  9. ^ a b c d Anand R, Wai T, Baker MJ, Kladt N, Schauss AC, Rugarli E, Langer T (Mar 2014). "The i-AAA protease YME1L and OMA1 cleave OPA1 to balance mitochondrial fusion and fission". The Journal of Cell Biology. 204 (6): 919–29. doi:10.1083/jcb.201308006. PMC 3998800. PMID 24616225.
  10. ^ Wiemerslage L, Lee D (2016). "Quantification of mitochondrial morphology in neurites of dopaminergic neurons using multiple parameters". J Neurosci Methods. 262: 56–65. doi:10.1016/j.jneumeth.2016.01.008. PMC 4775301. PMID 26777473.
  11. ^ a b c Carelli V, Musumeci O, Caporali L, Zanna C, La Morgia C, Del Dotto V, Porcelli AM, Rugolo M, Valentino ML, Iommarini L, Maresca A, Barboni P, Carbonelli M, Trombetta C, Valente EM, Patergnani S, Giorgi C, Pinton P, Rizzo G, Tonon C, Lodi R, Avoni P, Liguori R, Baruzzi A, Toscano A, Zeviani M (Mar 2015). "Syndromic parkinsonism and dementia associated with OPA1 missense mutations". Annals of Neurology. 78 (1): 21–38. doi:10.1002/ana.24410. PMC 5008165. PMID 25820230.
  12. ^ Fülöp L, Rajki A, Katona D, Szanda G, Spät A (Dec 2013). "Extramitochondrial OPA1 and adrenocortical function" (PDF). Molecular and Cellular Endocrinology. 381 (1–2): 70–9. doi:10.1016/j.mce.2013.07.021. PMID 23906536. S2CID 5657510.
  13. ^ Fülöp L, Szanda G, Enyedi B, Várnai P, Spät A (2011). "The effect of OPA1 on mitochondrial Ca²⁺ signaling". PLOS ONE. 6 (9): e25199. doi:10.1371/journal.pone.0025199. PMC 3182975. PMID 21980395.
  14. ^ Varanita T, Soriano ME, Romanello V, Zaglia T, Quintana-Cabrera R, Semenzato M, Menabò R, Costa V, Civiletto G, Pesce P, Viscomi C, Zeviani M, Di Lisa F, Mongillo M, Sandri M, Scorrano L (Jun 2015). "The OPA1-dependent mitochondrial cristae remodeling pathway controls atrophic, apoptotic, and ischemic tissue damage". Cell Metabolism. 21 (6): 834–44. doi:10.1016/j.cmet.2015.05.007. PMC 4457892. PMID 26039448.

Further reading