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Details on Person UniProt:Q03020 ISU1

Class:IdReferenceGeneProduct:233108
_chainChangeLogtransit peptide:1-27 added on Sat February 7 2015;chain:28-165 added on Sat February 7 2015
_displayNameUniProt:Q03020 ISU1
_timestamp2025-02-21 18:57:41
chaintransit peptide:1-27
chain:28-165
checksumE240845A27D2E9EE
commentFUNCTION Scaffold protein for the de novo synthesis of iron-sulfur (Fe-S) clusters within mitochondria, which is required for maturation of both mitochondrial and cytoplasmic [2Fe-2S] and [4Fe-4S] proteins (PubMed:10588895, PubMed:12970193, PubMed:14741370, PubMed:15123690, PubMed:16341089, PubMed:27738674, PubMed:31040179). First, a [2Fe-2S] cluster is transiently assembled on the scaffold proteins ISU1 and ISU2 (PubMed:12970193, PubMed:16341089, PubMed:31040179). In a second step, the cluster is released from ISU1/ISU2, transferred to glutaredoxin GRX5, followed by the formation of mitochondrial [2Fe-2S] proteins, the synthesis of [4Fe-4S] clusters and their target-specific insertion into the recipient apoproteins (PubMed:12970193, PubMed:23615440). Cluster assembly on ISU1/ISU2 depends on the function of the cysteine desulfurase complex NFS1-ISD11, which serves as the sulfur donor for cluster synthesis, the iron-binding protein frataxin (YFH1) as the putative iron donor, and the electron transfer chain comprised of ferredoxin reductase ARH1 and ferredoxin YAH1, which receive their electrons from NADH (PubMed:12970193, PubMed:14741370, PubMed:16341089, PubMed:25358379, PubMed:31040179). Fe-S cluster release from ISU1/ISU2 is achieved by interaction with the Hsp70 chaperone SSQ1, assisted by the DnaJ-like co-chaperone JAC1 and the nucleotide exchange factor MGE1 (PubMed:14741370, PubMed:15123690, PubMed:16431909, PubMed:23615440, PubMed:31040179). ISU1 is the major isoform in yeast, while ISU2 is not detectable in cells grown to stationary phase (PubMed:10588895). Also involved in production of a sulfur precursor required for thiolation of cytoplasmic tRNAs (PubMed:31040179).COFACTOR Binds 1 [2Fe-2S] cluster per subunit (By similarity). Zn(2+) binding stabilizes the monomeric form (PubMed:28548666).PATHWAY Cofactor biosynthesis; iron-sulfur cluster biosynthesis.SUBUNIT Homodimer, but can exist as monomers or trimers (PubMed:26941001, PubMed:28548666). Oligomerization may be regulated by Zn(2+) availability (PubMed:28548666). Component of the core Fe-S cluster (ISC) assembly machinery. Interacts with YFH1/frataxin with a 1 to 1 stoichiometry; the interaction is direct (PubMed:12947415, PubMed:14741370, PubMed:20815377, PubMed:25228696, PubMed:26941001, PubMed:28548666). Interacts with the mitochondrial co-chaperones JAC1 and SSQ1 (PubMed:12756240, PubMed:15123690, PubMed:22306468, PubMed:23615440, PubMed:23946486). Interacts with NFS1 (PubMed:23946486, PubMed:25228696). Interacts with YAH1/ferredoxin; interacts with the reduced form (PubMed:25358379).INTERACTION Cells deleted for both ISU1 and ISU2 have decreased activity of several respiratory enzymes that contain Fe-S clusters (PubMed:10468587, PubMed:10588895). As a result, cells grow poorly on carbon sources requiring respiration and also accumulate abnormally high levels of iron in their mitochondria (PubMed:10468587, PubMed:10588895). Knockdown of ISU1 in ISU2 knockout cells reduces cell growth, decreases cytosolic tRNA thiolation, and increases association between SSQ1 and GRX5 (PubMed:23615440, PubMed:27738674, PubMed:31040179).MISCELLANEOUS Present with 10800 molecules/cell in log phase SD medium.SIMILARITY Belongs to the NifU family.
created[InstanceEdit:217385] Schmidt, EE, 2008-03-27 06:23:53
descriptionrecommendedName: Iron sulfur cluster assembly protein 1, mitochondrial alternativeName: Iron sulfur cluster scaffold protein 1
geneNameISU1
NUA1
YPL135W
identifierQ03020
isSequenceChangedFALSE
keyword2Fe-2S
3D-structure
Iron
Iron-sulfur
Metal-binding
Mitochondrion
Reference proteome
Transit peptide
modified[InstanceEdit:354386] Schmidt, EE, 2008-06-18 04:45:12
[InstanceEdit:384350] Kanapin, AA, 2008-11-26 14:00:39
[InstanceEdit:392885] Kanapin, AA, 2009-03-09 12:07:18
[InstanceEdit:400710] Schmidt, EE, 2009-03-25 05:33:35
[InstanceEdit:423310] Kanapin, AA
[InstanceEdit:435478] Kanapin, AA
[InstanceEdit:435871] Kanapin, AA
[InstanceEdit:447347] Kanapin, AA
[InstanceEdit:525883] Kanapin, AA
[InstanceEdit:613449] Kanapin, AA
[InstanceEdit:797602] Kanapin, AA
[InstanceEdit:937368] Yung, CK
[InstanceEdit:1042053] Yung, CK
[InstanceEdit:1220657] Yung, CK
[InstanceEdit:1300696] Yung, CK
[InstanceEdit:1301627] Yung, CK
[InstanceEdit:1551960] Weiser, JD
[InstanceEdit:1995863] Weiser, JD
[InstanceEdit:2132304] Weiser, JD
[InstanceEdit:2265580] Weiser, JD
[InstanceEdit:2455454] Weiser, JD
[InstanceEdit:5433710] Weiser, JD
[InstanceEdit:5618415] Weiser, JD
[InstanceEdit:5634237] Weiser, JD
[InstanceEdit:5673015] Weiser, JD
[InstanceEdit:8944791] Weiser, JD
[InstanceEdit:9037114] Weiser, JD
[InstanceEdit:9637257] Weiser, JD
[InstanceEdit:9676415] Weiser, JD
[InstanceEdit:9715482] Weiser, JD
[InstanceEdit:9852000] Weiser, Joel, 2023-11-03
[InstanceEdit:9917590] Weiser, Joel, 2024-08-09
[InstanceEdit:9939033] Weiser, Joel, 2025-02-21
nameISU1
referenceDatabase[ReferenceDatabase:2] UniProt
secondaryIdentifierISU1_YEAST
D6W3N2
sequenceLength165
species[Species:68322] Saccharomyces cerevisiae
(referenceEntity)[EntityWithAccessionedSequence:8878828] ISU1 [mitochondrial matrix] [Saccharomyces cerevisiae]
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No pathways have been reviewed or authored by UniProt:Q03020 ISU1 (233108)