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Details on Person UniProt:Q9NZB8-1 MOCS1

Class:IdReferenceIsoform:414940
_chainChangeLogchain:1-636 added on Fri February 6 2015;chain:1-636 for 414940 removed on Fri Feb 20 2026;transit peptide:1-21 for 414940 added on Fri Feb 20 2026;chain:22-636 for 414940 added on Fri Feb 20 2026;propeptide:22-448 for 414940 added on Fri Feb 20 2026
_displayNameUniProt:Q9NZB8-1 MOCS1
_timestamp2026-02-20 21:51:14
chaintransit peptide:1-21
chain:22-636
propeptide:22-448
checksum6774A563BAC42120
commentFUNCTION Isoform MOCS1A and isoform MOCS1B probably form a complex that catalyzes the conversion of 5'-GTP to cyclic pyranopterin monophosphate (cPMP) (PubMed:11891227, PubMed:23627491, PubMed:29368224, PubMed:31996372). MOCS1A catalyzes the cyclization of GTP to (8S)-3',8-cyclo-7,8-dihydroguanosine 5'-triphosphate and MOCS1B catalyzes the subsequent conversion of (8S)-3',8-cyclo-7,8-dihydroguanosine 5'-triphosphate to cPMP (PubMed:11891227, PubMed:23627491, PubMed:29368224, PubMed:31996372).FUNCTION Has very weak catalytic activity.CATALYTIC ACTIVITY GTP + AH2 + S-adenosyl-L-methionine = (8S)-3',8-cyclo-7,8-dihydroguanosine 5'-triphosphate + 5'-deoxyadenosine + L-methionine + A + H(+)CATALYTIC ACTIVITY GTP + AH2 + S-adenosyl-L-methionine = (8S)-3',8-cyclo-7,8-dihydroguanosine 5'-triphosphate + 5'-deoxyadenosine + L-methionine + A + H(+)CATALYTIC ACTIVITY GTP + AH2 + S-adenosyl-L-methionine = (8S)-3',8-cyclo-7,8-dihydroguanosine 5'-triphosphate + 5'-deoxyadenosine + L-methionine + A + H(+)CATALYTIC ACTIVITY (8S)-3',8-cyclo-7,8-dihydroguanosine 5'-triphosphate = cyclic pyranopterin phosphate + diphosphateCOFACTOR Binds 2 [4Fe-4S] clusters. Binds 1 [4Fe-4S] cluster coordinated with 3 cysteines and an exchangeable S-adenosyl-L-methionine and 1 [4Fe-4S] cluster coordinated with 3 cysteines and the GTP-derived substrate.BIOPHYSICOCHEMICAL PROPERTIES kcat is 0.092 min(-1) for (8S)-3',8-cyclo-7,8-dihydroguanosine 5'-triphosphate.PATHWAY Cofactor biosynthesis; molybdopterin biosynthesis.SUBUNIT Isoform MOCS1A and isoform MOCS1B probably form a heterooligomer.SUBCELLULAR LOCATION Found in aggregates not co-localized with mitochondria.SUBCELLULAR LOCATION So far, the different types of MOCS1A and MOCS1B isoforms have been investigated independently and several combinations might be possible.TISSUE SPECIFICITY Isoform MOCS1A and isoform 2 are widely expressed.DISEASE The disease is caused by variants affecting the gene represented in this entry.MISCELLANEOUS The MOCS1 transcript is alternatively spliced resulting in production of alternative MOCS1A and MOCS1B products (PubMed:10917590, PubMed:11891227, PubMed:31996372). Type I splicing results in bicistronic transcripts with two open reading frames, of which only the first, MOCS1A, is translated due to a stop codon in exon 9 (PubMed:10917590, PubMed:11891227, PubMed:31996372). Alternative splicing of exon 9 leads to production of type II or III transcripts (where exon 9 is partially or fully removed) and where MOCS1B is translated as a fusion protein together with catalytically inactive MOCS1A; inactive MOCS1A is subsequently proteolytically cleaved during mitochondrial import and it is not known if it has a functional role (PubMed:10917590, PubMed:11891227, PubMed:31996372).MISCELLANEOUS Alternative splicing of the N-terminal exon 1 cassettes a-d appears to impart different properties to the protein; exon 1a targets MOCS1A to the mitochondrion whereas exon 1b at the N-terminus remains in the cytosol, exon 1c might stabilize MOCS1A, and exon 1d is essential for MOCS1A catalytic activity (PubMed:31996372). Exon 1a seems dispensable for targeting MOCS1B to the mitochondrion due to the presence of a linker region separating MOCS1A and MOCS1B that appears to facilitate mitochondrial import (PubMed:31996372).MISCELLANEOUS May be produced at very low levels due to a premature stop codon in the mRNA, leading to nonsense-mediated mRNA decay.MISCELLANEOUS Multidomain protein with inactive MOCS1A and active MOCS1B.SIMILARITY In the C-terminal section; belongs to the MoaC family.SIMILARITY In the N-terminal section; belongs to the radical SAM superfamily. MoaA family.CAUTION The C-terminus of MOCS1A was previously believed to be thiocarboxylated, but it is now known not to be the case.SEQUENCE CAUTION Alternative splicing in the MOCS1A-MOCS1B joining region.SEQUENCE CAUTION Alternative splicing in the MOCS1A-MOCS1B joining region.
created[InstanceEdit:400710] Schmidt, EE, 2009-03-25 05:33:35
descriptionrecommendedName: Molybdenum cofactor biosynthesis protein 1 alternativeName: Cell migration-inducing gene 11 protein alternativeName: Molybdenum cofactor synthesis-step 1 protein A-B domain recommendedName: fullName evidence="42"GTP 3',8-cyclase ecNumber evidence="25"4.1.99.22 alternativeName: fullName evidence="42"MOCS1A alternativeName: Molybdenum cofactor biosynthesis protein A /domain domain recommendedName: fullName evidence="42"Cyclic pyranopterin monophosphate synthase ecNumber evidence="20"4.6.1.17 alternativeName: fullName evidence="42"MOCS1B alternativeName: Molybdenum cofactor biosynthesis protein C /domain
geneNameMOCS1
MIG11
identifierQ9NZB8
isoformParent
isSequenceChangedFALSE
keyword4Fe-4S
Acetylation
Alternative splicing
Cytoplasm
Disease variant
GTP-binding
Iron
Iron-sulfur
Lyase
Metal-binding
Mitochondrion
Molybdenum cofactor biosynthesis
Nucleotide-binding
Phosphoprotein
Proteomics identification
Reference proteome
S-adenosyl-L-methionine
Transit peptide
modified[InstanceEdit:9836292] Weiser, Joel, 2023-05-25
[InstanceEdit:9852000] Weiser, Joel, 2023-11-03
[InstanceEdit:9926675] Weiser, Joel, 2024-11-03
[InstanceEdit:9939033] Weiser, Joel, 2025-02-21
[InstanceEdit:9983091] Weiser, Joel, 2026-02-20
nameMOCS1
referenceDatabase[ReferenceDatabase:2] UniProt
referenceGene[ReferenceDNASequence:8999003] ENSEMBL:ENSG00000124615 MOCS1 [Homo sapiens]
secondaryIdentifierMOCS1_HUMAN
B3KPT7
B4DTP1
O14940
O14941
O75710
Q5J7W0
Q5TCE1
Q5TCE2
Q5TCE6
Q5TCE9
Q5TCF0
Q5TCF1
Q8N418
Q9NZB7
Q9UEM1
sequenceLength636
species[Species:48887] Homo sapiens
variantIdentifierQ9NZB8-1
(referenceEntity)[EntityWithAccessionedSequence:947547] MOCS1-1 [cytosol] [Homo sapiens]
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No pathways have been reviewed or authored by UniProt:Q9NZB8-1 MOCS1 (414940)