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Details on Person UniProt:P99999 CYCS

Class:IdReferenceGeneProduct:53260
_chainChangeLoginitiator methionine:1 added on Fri February 6 2015;chain:2-105 added on Fri February 6 2015;initiator methionine:1 for 53260 removed on Fri Nov 03 2023;initiator methionine: for 53260 added on Fri Nov 03 2023;initiator methionine: for 53260 removed on Fri Aug 15 2025;initiator methionine:1 for 53260 added on Fri Aug 15 2025
_displayNameUniProt:P99999 CYCS
_timestamp2025-08-15 22:07:16
chaininitiator methionine:1
chain:2-105
checksum8EE9689E0102506B
commentFUNCTION Electron carrier protein. The oxidized form of the cytochrome c heme group can accept an electron from the heme group of the cytochrome c1 subunit of cytochrome reductase. Cytochrome c then transfers this electron to the cytochrome oxidase complex, the final protein carrier in the mitochondrial electron-transport chain.FUNCTION Plays a role in apoptosis. Suppression of the anti-apoptotic members or activation of the pro-apoptotic members of the Bcl-2 family leads to altered mitochondrial membrane permeability resulting in release of cytochrome c into the cytosol. Binding of cytochrome c to Apaf-1 triggers the activation of caspase-9, which then accelerates apoptosis by activating other caspases.INTERACTION Loosely associated with the inner membrane.PTM Binds 1 heme c group covalently per subunit.PTM Phosphorylation at Tyr-49 and Tyr-98 both reduce by half the turnover in the reaction with cytochrome c oxidase, down-regulating mitochondrial respiration.DISEASE The disease is caused by variants affecting the gene represented in this entry.SIMILARITY Belongs to the cytochrome c family.ONLINE INFORMATION Life shuttle - Issue 76 of November 2006ONLINE INFORMATION An unexpected place - Issue 88 of November 2007
descriptionrecommendedName: Cytochrome c
geneNameCYCS
CYC
identifierP99999
isSequenceChangedFALSE
keyword3D-structure
Acetylation
Apoptosis
Direct protein sequencing
Disease variant
Electron transport
Heme
Iron
Metal-binding
Mitochondrion
Phosphoprotein
Proteomics identification
Reference proteome
Respiratory chain
Transport
modified[InstanceEdit:9836292] Weiser, Joel, 2023-05-25
[InstanceEdit:9852000] Weiser, Joel, 2023-11-03
[InstanceEdit:9926675] Weiser, Joel, 2024-11-03
[InstanceEdit:9963647] Weiser, Joel, 2025-08-15
nameCYCS
referenceDatabase[ReferenceDatabase:2] UniProt
referenceGene[ReferenceDNASequence:2466374] ENSEMBL:ENSG00000172115 CYCS [Homo sapiens]
secondaryIdentifierCYC_HUMAN
A4D166
B2R4I1
P00001
Q6NUR2
Q6NX69
Q96BV4
sequenceLength105
species[Species:48887] Homo sapiens
(referenceEntity)[EntityWithAccessionedSequence:53259] CYCS [cytosol] [Homo sapiens]
[EntityWithAccessionedSequence:114244] CYCS [mitochondrial intermembrane space] [Homo sapiens]
[EntityWithAccessionedSequence:352607] Cytochrome c (oxidised) [mitochondrial inner membrane] [Homo sapiens]
[EntityWithAccessionedSequence:352608] apo-CYCS [mitochondrial inner membrane] [Homo sapiens]
[EntityWithAccessionedSequence:352609] Cytochrome c (reduced) [mitochondrial inner membrane] [Homo sapiens]
[EntityWithAccessionedSequence:5688308] AcK-CYCS [mitochondrial intermembrane space] [Homo sapiens]
(referenceSequence)[ModifiedResidue:5688287] N6-acetyl-L-lysine at unknown position
[GroupModifiedResidue:9866219] heme-bis-L-cysteine (ferroheme c di-L-cysteine(2-) residue) at 15
[GroupModifiedResidue:9866223] heme-bis-L-cysteine (ferroheme c di-L-cysteine(2-) residue) at 18
[GroupModifiedResidue:9866226] heme-bis-L-cysteine (ferriheme c di-L-cysteine(1-) residue) at 15
[GroupModifiedResidue:9866235] heme-bis-L-cysteine (ferriheme c di-L-cysteine(1-) residue) at 18
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No pathways have been reviewed or authored by UniProt:P99999 CYCS (53260)