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Murine supercomplex CIII2CIV in the intermediate locked conformation

Source organism: Mus musculus
Biochemical function: metal ion binding
Biological process: mitochondrial electron transport, ubiquinol to cytochrome c
Cellular component: mitochondrial inner membrane

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EC 7.1.1.8: Quinol--cytochrome-c reductase

Reaction catalysed:
Quinol + 2 ferricytochrome c(Side 2) = quinone + 2 ferrocytochrome c(Side 2) + 2 H(+)(Side 2)
Systematic name:
Quinol:ferricytochrome-c oxidoreductase
Alternative Name(s):
  • CoQH(2)--cytochrome c oxidoreductase
  • Coenzyme Q--cytochrome c reductase
  • Coenzyme QH(2)--cytochrome c reductase
  • Complex III (mitochondrial electron transport)
  • Cytochrome bc1 complex
  • Dihydrocoenzyme Q--cytochrome c reductase
  • Mitochondrial electron transport complex III
  • QH(2):cytochrome c oxidoreductase
  • Reduced coenzyme Q-cytochrome c reductase
  • Reduced ubiquinone--cytochrome c oxidoreductase
  • Reduced ubiquinone--cytochrome c reductase, complex III (mitochondrial electron transport)
  • Ubihydroquinol:cytochrome c oxidoreductase
  • Ubiquinol--cytochrome c oxidoreductase
  • Ubiquinol--cytochrome c-2 oxidoreductase
  • Ubiquinol--cytochrome c1 oxidoreductase
  • Ubiquinol--cytochrome c2 reductase
  • Ubiquinol--cytochrome-c reductase
  • Ubiquinol:ferricytochrome-c oxidoreductase
  • Ubiquinone--cytochrome b-c(1) oxidoreductase
  • Ubiquinone--cytochrome c oxidoreductase
  • Ubiquinone--cytochrome-c oxidoreductase
  • Ubiquinone-cytochrome c reductase

EC 7.1.1.9: Cytochrome-c oxidase

Reaction catalysed:
4 ferrocytochrome c + O(2) + 8 H(+)(Side 1) = 4 ferricytochrome c + 4 H(2)O(Side 2)
Systematic name:
Ferrocytochrome-c:oxygen oxidoreductase
Alternative Name(s):
  • Complex IV (mitochondrial electron transport)
  • Cytochrome a3
  • Cytochrome aa3
  • Cytochrome ba(3)
  • Cytochrome bb3
  • Cytochrome caa(3)
  • Cytochrome cbb(3)
  • Cytochrome oxidase
  • Ferrocytochrome c oxidase
  • Indophenol oxidase
  • Indophenolase
  • NADH cytochrome c oxidase
  • Warburg's respiratory enzyme

GO terms

Sequence families

Pfam Protein families (Pfam)
PF05193
Domain description: Peptidase M16 inactive domain
Occurring in:
  1. Cytochrome b-c1 complex subunit 1, mitochondrial
  2. Cytochrome b-c1 complex subunit 2, mitochondrial
The deposited structure of PDB entry 7o3e contains 2 copies of Pfam domain PF05193 (Peptidase M16 inactive domain) in Cytochrome b-c1 complex subunit 1, mitochondrial. Showing 1 copy in chain A.
The deposited structure of PDB entry 7o3e contains 2 copies of Pfam domain PF05193 (Peptidase M16 inactive domain) in Cytochrome b-c1 complex subunit 2, mitochondrial. Showing 1 copy in chain B.

PF00675
Domain description: Insulinase (Peptidase family M16)
Occurring in:
  1. Cytochrome b-c1 complex subunit 1, mitochondrial
  2. Cytochrome b-c1 complex subunit 2, mitochondrial
The deposited structure of PDB entry 7o3e contains 2 copies of Pfam domain PF00675 (Insulinase (Peptidase family M16)) in Cytochrome b-c1 complex subunit 1, mitochondrial. Showing 1 copy in chain A.
The deposited structure of PDB entry 7o3e contains 2 copies of Pfam domain PF00675 (Insulinase (Peptidase family M16)) in Cytochrome b-c1 complex subunit 2, mitochondrial. Showing 1 copy in chain B.

PF05365
Domain description: Ubiquinol-cytochrome C reductase, UQCRX/QCR9 like
Occurring in:
  1. Cytochrome b-c1 complex subunit 9
The deposited structure of PDB entry 7o3e contains 2 copies of Pfam domain PF05365 (Ubiquinol-cytochrome C reductase, UQCRX/QCR9 like) in Cytochrome b-c1 complex subunit 9. Showing 1 copy in chain CA [auth J].

PF02320
Domain description: Ubiquinol-cytochrome C reductase hinge protein
Occurring in:
  1. Cytochrome b-c1 complex subunit 6, mitochondrial
The deposited structure of PDB entry 7o3e contains 2 copies of Pfam domain PF02320 (Ubiquinol-cytochrome C reductase hinge protein) in Cytochrome b-c1 complex subunit 6, mitochondrial. Showing 1 copy in chain G [auth H].

PF02939
Domain description: UcrQ family
Occurring in:
  1. Cytochrome b-c1 complex subunit 8
The deposited structure of PDB entry 7o3e contains 2 copies of Pfam domain PF02939 (UcrQ family) in Cytochrome b-c1 complex subunit 8. Showing 1 copy in chain M [auth R].

PF02271
Domain description: Ubiquinol-cytochrome C reductase complex 14kD subunit
Occurring in:
  1. Cytochrome b-c1 complex subunit 7
The deposited structure of PDB entry 7o3e contains 2 copies of Pfam domain PF02271 (Ubiquinol-cytochrome C reductase complex 14kD subunit) in Cytochrome b-c1 complex subunit 7. Showing 1 copy in chain E [auth F].

PF02167
Domain description: Cytochrome C1 family
Occurring in:
  1. Cytochrome c1, heme protein, mitochondrial
The deposited structure of PDB entry 7o3e contains 2 copies of Pfam domain PF02167 (Cytochrome C1 family) in Cytochrome c1, heme protein, mitochondrial. Showing 1 copy in chain D.

PF00032
Domain description: Cytochrome b(C-terminal)/b6/petD
Occurring in:
  1. Cytochrome b
The deposited structure of PDB entry 7o3e contains 2 copies of Pfam domain PF00032 (Cytochrome b(C-terminal)/b6/petD) in Cytochrome b. Showing 1 copy in chain C.

PF00033
Domain description: Cytochrome b/b6/petB
Occurring in:
  1. Cytochrome b
The deposited structure of PDB entry 7o3e contains 2 copies of Pfam domain PF00033 (Cytochrome b/b6/petB) in Cytochrome b. Showing 1 copy in chain C.

PF02285
Domain description: Cytochrome oxidase c subunit VIII
Occurring in:
  1. Cytochrome c oxidase subunit 8B, mitochondrial
The deposited structure of PDB entry 7o3e contains 1 copy of Pfam domain PF02285 (Cytochrome oxidase c subunit VIII) in Cytochrome c oxidase subunit 8B, mitochondrial. Showing 1 copy in chain BA [auth m].

PF02935
Domain description: Cytochrome c oxidase subunit VIIc
Occurring in:
  1. Cytochrome c oxidase subunit 7C, mitochondrial
The deposited structure of PDB entry 7o3e contains 1 copy of Pfam domain PF02935 (Cytochrome c oxidase subunit VIIc) in Cytochrome c oxidase subunit 7C, mitochondrial. Showing 1 copy in chain AA [auth l].

PF05392
Domain description: Cytochrome C oxidase chain VIIB
Occurring in:
  1. Cytochrome c oxidase subunit 7B, mitochondrial
The deposited structure of PDB entry 7o3e contains 1 copy of Pfam domain PF05392 (Cytochrome C oxidase chain VIIB) in Cytochrome c oxidase subunit 7B, mitochondrial. Showing 1 copy in chain Z [auth k].

PF02937
Domain description: Cytochrome c oxidase subunit VIc
Occurring in:
  1. Cytochrome c oxidase subunit 6C
The deposited structure of PDB entry 7o3e contains 1 copy of Pfam domain PF02937 (Cytochrome c oxidase subunit VIc) in Cytochrome c oxidase subunit 6C. Showing 1 copy in chain Y [auth i].

PF02297
Domain description: Cytochrome oxidase c subunit VIb
Occurring in:
  1. Cytochrome c oxidase subunit 6B1
The deposited structure of PDB entry 7o3e contains 1 copy of Pfam domain PF02297 (Cytochrome oxidase c subunit VIb) in Cytochrome c oxidase subunit 6B1. Showing 1 copy in chain X [auth h].

PF02046
Domain description: Cytochrome c oxidase subunit VIa
Occurring in:
  1. Cytochrome c oxidase subunit 6A2, mitochondrial
The deposited structure of PDB entry 7o3e contains 1 copy of Pfam domain PF02046 (Cytochrome c oxidase subunit VIa) in Cytochrome c oxidase subunit 6A2, mitochondrial. Showing 1 copy in chain W [auth g].

PF01215
Domain description: Cytochrome c oxidase subunit Vb
Occurring in:
  1. Cytochrome c oxidase subunit 5B, mitochondrial
The deposited structure of PDB entry 7o3e contains 1 copy of Pfam domain PF01215 (Cytochrome c oxidase subunit Vb) in Cytochrome c oxidase subunit 5B, mitochondrial. Showing 1 copy in chain V [auth f].

PF02284
Domain description: Cytochrome c oxidase subunit Va
Occurring in:
  1. Cytochrome c oxidase subunit 5A, mitochondrial
The deposited structure of PDB entry 7o3e contains 1 copy of Pfam domain PF02284 (Cytochrome c oxidase subunit Va) in Cytochrome c oxidase subunit 5A, mitochondrial. Showing 1 copy in chain U [auth e].

PF02936
Domain description: Cytochrome c oxidase subunit IV
Occurring in:
  1. Cytochrome c oxidase subunit 4 isoform 1, mitochondrial
The deposited structure of PDB entry 7o3e contains 1 copy of Pfam domain PF02936 (Cytochrome c oxidase subunit IV) in Cytochrome c oxidase subunit 4 isoform 1, mitochondrial. Showing 1 copy in chain T [auth d].

PF00510
Domain description: Cytochrome c oxidase subunit III
Occurring in:
  1. Cytochrome c oxidase subunit 3
The deposited structure of PDB entry 7o3e contains 1 copy of Pfam domain PF00510 (Cytochrome c oxidase subunit III) in Cytochrome c oxidase subunit 3. Showing 1 copy in chain S [auth c].

PF00116
Domain description: Cytochrome C oxidase subunit II, periplasmic domain
Occurring in:
  1. Cytochrome c oxidase subunit 2
The deposited structure of PDB entry 7o3e contains 1 copy of Pfam domain PF00116 (Cytochrome C oxidase subunit II, periplasmic domain) in Cytochrome c oxidase subunit 2. Showing 1 copy in chain R [auth b].

PF02790
Domain description: Cytochrome C oxidase subunit II, transmembrane domain
Occurring in:
  1. Cytochrome c oxidase subunit 2
The deposited structure of PDB entry 7o3e contains 1 copy of Pfam domain PF02790 (Cytochrome C oxidase subunit II, transmembrane domain) in Cytochrome c oxidase subunit 2. Showing 1 copy in chain R [auth b].

PF00115
Domain description: Cytochrome C and Quinol oxidase polypeptide I
Occurring in:
  1. Cytochrome c oxidase subunit 1
The deposited structure of PDB entry 7o3e contains 1 copy of Pfam domain PF00115 (Cytochrome C and Quinol oxidase polypeptide I) in Cytochrome c oxidase subunit 1. Showing 1 copy in chain Q [auth a].

PF09165
Domain description: Ubiquinol-cytochrome c reductase 8 kDa, N-terminal
Occurring in:
  1. Cytochrome b-c1 complex subunit 9
The deposited structure of PDB entry 7o3e contains 1 copy of Pfam domain PF09165 (Ubiquinol-cytochrome c reductase 8 kDa, N-terminal) in Cytochrome b-c1 complex subunit 9. Showing 1 copy in chain O [auth T].

PF00355
Domain description: Rieske [2Fe-2S] domain
Occurring in:
  1. Cytochrome b-c1 complex subunit Rieske, mitochondrial
The deposited structure of PDB entry 7o3e contains 1 copy of Pfam domain PF00355 (Rieske [2Fe-2S] domain) in Cytochrome b-c1 complex subunit Rieske, mitochondrial. Showing 1 copy in chain K [auth P] (this domain is out of the observed residue ranges!).

PF02921
Domain description: Ubiquinol cytochrome reductase transmembrane region
Occurring in:
  1. Cytochrome b-c1 complex subunit Rieske, mitochondrial
The deposited structure of PDB entry 7o3e contains 1 copy of Pfam domain PF02921 (Ubiquinol cytochrome reductase transmembrane region) in Cytochrome b-c1 complex subunit Rieske, mitochondrial. Showing 1 copy in chain K [auth P].

PF02238
Domain description: Cytochrome c oxidase subunit VII
Occurring in:
  1. Cox7a2l protein
The deposited structure of PDB entry 7o3e contains 1 copy of Pfam domain PF02238 (Cytochrome c oxidase subunit VII) in Cox7a2l protein. Showing 1 copy in chain P [auth I].

InterPro InterPro annotations
IPR002326
Domain description: Cytochrome c1
Occurring in:
  1. Cytochrome c1, heme protein, mitochondrial
IPR000883
Domain description: Cytochrome c oxidase subunit I
Occurring in:
  1. Cytochrome c oxidase subunit 1
IPR011249
Domain description: Metalloenzyme, LuxS/M16 peptidase-like
Occurring in:
  1. Cytochrome b-c1 complex subunit 1, mitochondrial
  2. Cytochrome b-c1 complex subunit 2, mitochondrial
IPR003197
Domain description: Cytochrome b-c1 complex subunit 7
Occurring in:
  1. Cytochrome b-c1 complex subunit 7
IPR005798
Domain description: Cytochrome b/b6, C-terminal
Occurring in:
  1. Cytochrome b
IPR005797
Domain description: Cytochrome b/b6, N-terminal domain
Occurring in:
  1. Cytochrome b
IPR003213
Domain description: Cytochrome c oxidase, subunit VIb
Occurring in:
  1. Cytochrome c oxidase subunit 6B1
IPR001349
Domain description: Cytochrome c oxidase, subunit VIa
Occurring in:
  1. Cytochrome c oxidase subunit 6A2, mitochondrial
IPR002124
Domain description: Cytochrome c oxidase, subunit Vb
Occurring in:
  1. Cytochrome c oxidase subunit 5B, mitochondrial
IPR013288
Domain description: Cytochrome c oxidase subunit IV
Occurring in:
  1. Cytochrome c oxidase subunit 4 isoform 1, mitochondrial
IPR008027
Domain description: Cytochrome b-c1 complex subunit 9
Occurring in:
  1. Cytochrome b-c1 complex subunit 9
IPR036656
Domain description: Cytochrome b-c1 complex subunit 9 superfamily
Occurring in:
  1. Cytochrome b-c1 complex subunit 9
IPR036811
Domain description: Ubiquinol-cytochrome C reductase hinge domain superfamily
Occurring in:
  1. Cytochrome b-c1 complex subunit 6, mitochondrial
IPR003422
Domain description: Cytochrome b-c1 complex, subunit 6
Occurring in:
  1. Cytochrome b-c1 complex subunit 6, mitochondrial
IPR036642
Domain description: Cytochrome b-c1 complex subunit 8 superfamily
Occurring in:
  1. Cytochrome b-c1 complex subunit 8
IPR004205
Domain description: Cytochrome b-c1 complex subunit 8
Occurring in:
  1. Cytochrome b-c1 complex subunit 8
IPR036544
Domain description: Cytochrome b-c1 complex subunit 7 superfamily
Occurring in:
  1. Cytochrome b-c1 complex subunit 7
IPR036909
Domain description: Cytochrome c-like domain superfamily
Occurring in:
  1. Cytochrome c1, heme protein, mitochondrial
IPR007863
Domain description: Peptidase M16, C-terminal
Occurring in:
  1. Cytochrome b-c1 complex subunit 1, mitochondrial
  2. Cytochrome b-c1 complex subunit 2, mitochondrial
IPR011765
Domain description: Peptidase M16, N-terminal
Occurring in:
  1. Cytochrome b-c1 complex subunit 1, mitochondrial
  2. Cytochrome b-c1 complex subunit 2, mitochondrial
IPR003204
Domain description: Cytochrome c oxidase, subunit Va/VI
Occurring in:
  1. Cytochrome c oxidase subunit 5A, mitochondrial
IPR004203
Domain description: Cytochrome c oxidase subunit IV family
Occurring in:
  1. Cytochrome c oxidase subunit 4 isoform 1, mitochondrial
IPR005805
Domain description: Rieske iron-sulphur protein, C-terminal
Occurring in:
  1. Cytochrome b-c1 complex subunit Rieske, mitochondrial
IPR036548
Domain description: Cytochrome c oxidase, subunit 8 superfamily
Occurring in:
  1. Cytochrome c oxidase subunit 8B, mitochondrial
IPR036636
Domain description: Cytochrome c oxidase subunit VIIc superfamily
Occurring in:
  1. Cytochrome c oxidase subunit 7C, mitochondrial
IPR004202
Domain description: Cytochrome c oxidase subunit VIIc
Occurring in:
  1. Cytochrome c oxidase subunit 7C, mitochondrial
IPR023272
Domain description: Cytochrome C oxidase, subunit VIIB domain superfamily
Occurring in:
  1. Cytochrome c oxidase subunit 7B, mitochondrial
IPR008433
Domain description: Cytochrome C oxidase, subunit VIIB
Occurring in:
  1. Cytochrome c oxidase subunit 7B, mitochondrial
IPR037169
Domain description: Mitochondrial cytochrome c oxidase subunit VIc/VIIs superfamily
Occurring in:
  1. Cytochrome c oxidase subunit 6C
IPR036549
Domain description: Cytochrome c oxidase subunit 6B/Cytochrome c oxidase assembly factor 6-like superfamily
Occurring in:
  1. Cytochrome c oxidase subunit 6B1
IPR036418
Domain description: Cytochrome c oxidase, subunit VIa superfamily
Occurring in:
  1. Cytochrome c oxidase subunit 6A2, mitochondrial
IPR036545
Domain description: Cytochrome c oxidase, subunit Va/VI superfamily
Occurring in:
  1. Cytochrome c oxidase subunit 5A, mitochondrial
IPR036639
Domain description: Cytochrome c oxidase subunit IV superfamily
Occurring in:
  1. Cytochrome c oxidase subunit 4 isoform 1, mitochondrial
IPR000298
Domain description: Cytochrome c oxidase subunit III-like
Occurring in:
  1. Cytochrome c oxidase subunit 3
IPR002429
Domain description: Cytochrome c oxidase subunit II-like C-terminal
Occurring in:
  1. Cytochrome c oxidase subunit 2
IPR008972
Domain description: Cupredoxin
Occurring in:
  1. Cytochrome c oxidase subunit 2
IPR036257
Domain description: Cytochrome C oxidase subunit II, transmembrane domain superfamily
Occurring in:
  1. Cytochrome c oxidase subunit 2
IPR011759
Domain description: Cytochrome C oxidase subunit II, transmembrane domain
Occurring in:
  1. Cytochrome c oxidase subunit 2
IPR036927
Domain description: Cytochrome c oxidase-like, subunit I superfamily
Occurring in:
  1. Cytochrome c oxidase subunit 1
IPR017941
Domain description: Rieske [2Fe-2S] iron-sulphur domain
Occurring in:
  1. Cytochrome b-c1 complex subunit Rieske, mitochondrial
IPR036922
Domain description: Rieske [2Fe-2S] iron-sulphur domain superfamily
Occurring in:
  1. Cytochrome b-c1 complex subunit Rieske, mitochondrial
IPR036539
Domain description: Cytochrome c oxidase, subunit VIIa superfamily
Occurring in:
  1. Cox7a2l protein
IPR003177
Domain description: Cytochrome c oxidase subunit VIIa, metazoa
Occurring in:
  1. Cox7a2l protein
IPR023184
Domain description: Ubiquinol-cytochrome C reductase hinge domain
Occurring in:
  1. Cytochrome b-c1 complex subunit 6, mitochondrial
IPR021157
Domain description: Cytochrome c1, transmembrane anchor, C-terminal
Occurring in:
  1. Cytochrome c1, heme protein, mitochondrial
IPR009056
Domain description: Cytochrome c-like domain
Occurring in:
  1. Cytochrome c1, heme protein, mitochondrial
IPR036150
Domain description: Cytochrome b/b6, C-terminal domain superfamily
Occurring in:
  1. Cytochrome b
IPR030689
Domain description: Cytochrome b
Occurring in:
  1. Cytochrome b
IPR027387
Domain description: Cytochrome b/b6-like domain superfamily
Occurring in:
  1. Cytochrome b
IPR016174
Domain description: Di-haem cytochrome, transmembrane
Occurring in:
  1. Cytochrome b
IPR001431
Domain description: Peptidase M16, zinc-binding site
Occurring in:
  1. Cytochrome b-c1 complex subunit 2, mitochondrial
IPR003205
Domain description: Cytochrome c oxidase, subunit 8
Occurring in:
  1. Cytochrome c oxidase subunit 8B, mitochondrial
IPR034884
Domain description: Mitochondrial cytochrome c oxidase subunit VIc/VIIs
Occurring in:
  1. Cytochrome c oxidase subunit 6C
IPR004204
Domain description: Cytochrome c oxidase subunit 7e/7s
Occurring in:
  1. Cytochrome c oxidase subunit 6C
IPR018507
Domain description: Cytochrome c oxidase, subunit VIa, conserved site
Occurring in:
  1. Cytochrome c oxidase subunit 6A2, mitochondrial
IPR036972
Domain description: Cytochrome c oxidase, subunit Vb superfamily
Occurring in:
  1. Cytochrome c oxidase subunit 5B, mitochondrial
IPR013833
Domain description: Cytochrome c oxidase, subunit III, 4-helical bundle
Occurring in:
  1. Cytochrome c oxidase subunit 3
IPR033945
Domain description: Cytochrome c oxidase subunit III domain
Occurring in:
  1. Cytochrome c oxidase subunit 3
IPR024791
Domain description: Cytochrome c oxidase subunit III
Occurring in:
  1. Cytochrome c oxidase subunit 3
IPR035973
Domain description: Cytochrome c oxidase subunit III-like superfamily
Occurring in:
  1. Cytochrome c oxidase subunit 3
IPR001505
Domain description: Copper centre Cu(A)
Occurring in:
  1. Cytochrome c oxidase subunit 2
IPR034210
Domain description: Cytochrome c oxidase subunit 2, C-terminal
Occurring in:
  1. Cytochrome c oxidase subunit 2
IPR014222
Domain description: Cytochrome c oxidase, subunit II
Occurring in:
  1. Cytochrome c oxidase subunit 2
IPR045187
Domain description: Cytochrome c/quinol oxidase subunit II
Occurring in:
  1. Cytochrome c oxidase subunit 2
IPR023615
Domain description: Cytochrome c oxidase, subunit I, copper-binding site
Occurring in:
  1. Cytochrome c oxidase subunit 1
IPR033944
Domain description: Cytochrome c oxidase subunit I domain
Occurring in:
  1. Cytochrome c oxidase subunit 1
IPR023616
Domain description: Cytochrome c oxidase-like, subunit I domain
Occurring in:
  1. Cytochrome c oxidase subunit 1
IPR015248
Domain description: Ubiquinol-cytochrome c reductase iron-sulphur subunit, N-terminal
Occurring in:
  1. Cytochrome b-c1 complex subunit 9
IPR011070
Domain description: Globular protein, non-globular alpha/beta subunit
Occurring in:
  1. Cytochrome b-c1 complex subunit 9
IPR006317
Domain description: Ubiquinol-cytochrome c reductase, iron-sulphur subunit
Occurring in:
  1. Cytochrome b-c1 complex subunit Rieske, mitochondrial
IPR014349
Domain description: Rieske iron-sulphur protein
Occurring in:
  1. Cytochrome b-c1 complex subunit Rieske, mitochondrial
IPR004192
Domain description: Cytochrome b-c1 complex subunit Rieske, transmembrane domain
Occurring in:
  1. Cytochrome b-c1 complex subunit Rieske, mitochondrial
IPR037008
Domain description: Cytochrome bc1 complex subunit Rieske, transmembrane domain superfamily
Occurring in:
  1. Cytochrome b-c1 complex subunit Rieske, mitochondrial
IPR039297
Domain description: Cytochrome c oxidase subunit VII
Occurring in:
  1. Cox7a2l protein
IPR017267
Domain description: Cytochrome c oxidase subunit VIIa-related, mitochondrial
Occurring in:
  1. Cox7a2l protein

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