Reviewed, UniProtKB/Swiss-Prot O00391 (QSOX1_HUMAN)

Names and origin

Protein names

Recommended name:
    Sulfhydryl oxidase 1
      Short name=hQSOX
    EC=1.8.3.2
Alternative name(s):
    Quiescin Q6

Gene names

Name:	QSOX1
Synonyms:	QSCN6
ORF Names:	UNQ2520/PRO6013

Organism

Homo sapiens (Human) [Complete proteome]

Taxonomic identifier

9606 [NCBI]

Taxonomic lineage

Eukaryota › Metazoa › Chordata › Craniata › Vertebrata › Euteleostomi › Mammalia › Eutheria › Euarchontoglires › Primates › Haplorrhini › Catarrhini › Hominidae › Homo

Protein attributes

Sequence length	747 AA.
Sequence status	Complete.
Sequence processing	The displayed sequence is further processed into a mature form.
Protein existence	Evidence at protein level.

General annotation (Comments)

Function	Catalyzes the oxidation of sulfhydryl groups in peptide and protein thiols to disulfides with the reduction of oxygen to hydrogen peroxide. May contribute to disulfide bond formation in a variety of secreted proteins. In fibroblasts, it may have tumor-suppressing capabilities being involved in growth regulation. Ref.2 Ref.7 Ref.8 Ref.10 Ref.12
Catalytic activity	4 R'C(R)SH + O2 = 2 R'C(R)S-S(R)CR' + 2 H2O.
Cofactor	Binds 1 FAD per subunit By similarity.
Subunit structure	Monomer By similarity.
Subcellular location	Isoform 1: Golgi apparatus membrane; Single-pass membrane protein. Ref.8 Ref.12 Isoform 2: Secreted › extracellular space. Note: Found in the extracellular medium of quiescent cells but is not found in proliferating cells. Ref.8 Ref.12
Tissue specificity	Expressed in heart, placenta, lung, liver, skeletal muscle, pancreas and very weakly in brain and kidney. Ref.8 Ref.9
Induction	Induced in quiescent cells just as fibroblasts begin to leave the proliferative cycle and enter quiescence. Ref.7 Ref.8 Ref.1
Miscellaneous	'Quiescin Q6' means that it was the sixth clone to be found at a higher level of expression in quiescent fibroblasts.
Sequence similarities	Belongs to the quiescin-sulfhydryl oxidase (QSOX) family. Contains 1 ERV/ALR sulfhydryl oxidase domain. Contains 1 thioredoxin domain.

Ontologies

Keywords
Cellular component	Golgi apparatus Membrane Secreted
Coding sequence diversity	Alternative splicing Polymorphism
Domain	Signal Transmembrane
Ligand	FAD Flavoprotein
Molecular function	Oxidoreductase
PTM	Glycoprotein
Technical term	Complete proteome
Gene Ontology (GO)
Biological process	cell redox homeostasis Inferred from electronic annotation. Source: InterPro oxidation reduction Inferred from electronic annotation. Source: UniProtKB-KW protein thiol-disulfide exchange Ref.12 Inferred from genetic interaction. Source: UniProtKB
Cellular component	extracellular space Ref.8 Inferred from direct assay. Source: UniProtKB integral to Golgi membrane Ref.12 Inferred from direct assay. Source: UniProtKB
Molecular function	flavin-linked sulfhydryl oxidase activity Ref.12 Inferred from genetic interaction. Source: UniProtKB
Complete GO annotation...

Alternative products

This entry describes 2 isoforms produced by alternative splicing. [Align] [Select]

Isoform 1 (identifier: O00391-1)

Also known as: a; QSOX-L;

This isoform has been chosen as the 'canonical' sequence. All positional information in this entry refers to it. This is also the sequence that appears in the downloadable versions of the entry.

Isoform 2 (identifier: O00391-2)

Also known as: b; QSOX-S;

The sequence of this isoform differs from the canonical sequence as follows:
     603-604: AS → LI
     605-747: Missing.

Note: Found in the extracellular medium of quiescent cells but is not found in proliferating cells. Ref.8 Ref.12 No experimental confirmation available.

Sequence annotation (Features)

	Feature key	Position(s)	Length	Description	Graphical view	Feature identifier
Molecule processing
	Signal peptide	1 – 29	29	Potential
	Chain	30 – 747	718	Sulfhydryl oxidase 1		PRO_0000249533
Regions
	Transmembrane	710 – 730	21	Potential
	Domain	36 – 156	121	Thioredoxin
	Domain	396 – 503	108	ERV/ALR sulfhydryl oxidase
Amino acid modifications
	Glycosylation	130	1	N-linked (GlcNAc...) Ref.11
	Glycosylation	243	1	N-linked (GlcNAc...) Potential
	Glycosylation	575	1	N-linked (GlcNAc...) Potential
Natural variations
	Alternative sequence	603 – 604	2	AS → LI in isoform 2.		VSP_020489
	Alternative sequence	605 – 747	143	Missing in isoform 2.		VSP_020490
	Natural variant	114	1	N → S: dbSNP rs3894211.		VAR_027429
	Natural variant	200	1	G → A: dbSNP rs17855475. Ref.2 Ref.4 Ref.6		VAR_027430
	Natural variant	256	1	R → M: dbSNP rs4360492.		VAR_027431
	Natural variant	294	1	A → S: dbSNP rs2278943.		VAR_027432
	Natural variant	444	1	H → R: dbSNP rs12371. Ref.2		VAR_027433
	Natural variant	591	1	N → H: dbSNP rs3738115.		VAR_027434
	Natural variant	605	1	R → P: dbSNP rs16855466.		VAR_053652

Sequences

	Sequence		Length	Mass (Da)
	Isoform 1 (a) (QSOX-L) [UniParc]. Last modified June 1, 2001. Version 3. Checksum: 52639D09A50E00C5	FASTA	747	82,578
	10 20 30 40 50 60 MRRCNSGSGP PPSLLLLLLW LLAVPGANAA PRSALYSPSD PLTLLQADTV RGAVLGSRSA 70 80 90 100 110 120 WAVEFFASWC GHCIAFAPTW KALAEDVKAW RPALYLAALD CAEETNSAVC RDFNIPGFPT 130 140 150 160 170 180 VRFFKAFTKN GSGAVFPVAG ADVQTLRERL IDALESHHDT WPPACPPLEP AKLEEIDGFF 190 200 210 220 230 240 ARNNEEYLAL IFEKGGSYLG REVALDLSQH KGVAVRRVLN TEANVVRKFG VTDFPSCYLL 250 260 270 280 290 300 FRNGSVSRVP VLMESRSFYT AYLQRLSGLT REAAQTTVAP TTANKIAPTV WKLADRSKIY 310 320 330 340 350 360 MADLESALHY ILRIEVGRFP VLEGQRLVAL KKFVAVLAKY FPGRPLVQNF LHSVNEWLKR 370 380 390 400 410 420 QKRNKIPYSF FKTALDDRKE GAVLAKKVNW IGCQGSEPHF RGFPCSLWVL FHFLTVQAAR 430 440 450 460 470 480 QNVDHSQEAA KAKEVLPAIR GYVHYFFGCR DCASHFEQMA AASMHRVGSP NAAVLWLWSS 490 500 510 520 530 540 HNRVNARLAG APSEDPQFPK VQWPPRELCS ACHNERLDVP VWDVEATLNF LKAHFSPSNI 550 560 570 580 590 600 ILDFPAAGSA ARRDVQNVAA APELAMGALE LESRNSTLDP GKPEMMKSPT NTTPHVPAEG 610 620 630 640 650 660 PEASRPPKLH PGLRAAPGQE PPEHMAELQR NEQEQPLGQW HLSKRDTGAA LLAESRAEKN 670 680 690 700 710 720 RLWGPLEVRR VGRSSKQLVD IPEGQLEARA GRGRGQWLQV LGGGFSYLDI SLCVGLYSLS 730 740 FMGLLAMYTY FQAKIRALKG HAGHPAA
	Isoform 2 (b) (QSOX-S). Checksum: B557EE4D1525E7FB	FASTA	604	66,861
	10 20 30 40 50 60 MRRCNSGSGP PPSLLLLLLW LLAVPGANAA PRSALYSPSD PLTLLQADTV RGAVLGSRSA 70 80 90 100 110 120 WAVEFFASWC GHCIAFAPTW KALAEDVKAW RPALYLAALD CAEETNSAVC RDFNIPGFPT 130 140 150 160 170 180 VRFFKAFTKN GSGAVFPVAG ADVQTLRERL IDALESHHDT WPPACPPLEP AKLEEIDGFF 190 200 210 220 230 240 ARNNEEYLAL IFEKGGSYLG REVALDLSQH KGVAVRRVLN TEANVVRKFG VTDFPSCYLL 250 260 270 280 290 300 FRNGSVSRVP VLMESRSFYT AYLQRLSGLT REAAQTTVAP TTANKIAPTV WKLADRSKIY 310 320 330 340 350 360 MADLESALHY ILRIEVGRFP VLEGQRLVAL KKFVAVLAKY FPGRPLVQNF LHSVNEWLKR 370 380 390 400 410 420 QKRNKIPYSF FKTALDDRKE GAVLAKKVNW IGCQGSEPHF RGFPCSLWVL FHFLTVQAAR 430 440 450 460 470 480 QNVDHSQEAA KAKEVLPAIR GYVHYFFGCR DCASHFEQMA AASMHRVGSP NAAVLWLWSS 490 500 510 520 530 540 HNRVNARLAG APSEDPQFPK VQWPPRELCS ACHNERLDVP VWDVEATLNF LKAHFSPSNI 550 560 570 580 590 600 ILDFPAAGSA ARRDVQNVAA APELAMGALE LESRNSTLDP GKPEMMKSPT NTTPHVPAEG PELI

References

	« Hide 'large scale' referencesShow 'large scale' references »
[1]	"The quiescin Q6 gene (QSCN6) is a fusion of two ancient gene families: thioredoxin and ERV1." Coppock D.L., Cina-Poppe D., Gilleran S. Genomics 54:460-468(1998) [PubMed: 9878249] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [MRNA] (ISOFORM 1), INDUCTION. Tissue: Lung.
[2]	"Identification and expression of a new splicing variant of FAD-sulfhydryl oxidase in adult rat brain." Radom J., Colin D., Thiebault F., Dognin-Bergeret M.J., Mairet-Coello G., Esnard-Feve A., Fellmann D., Jouvenot M. Biochim. Biophys. Acta 1759:225-233(2006) [PubMed: 16806532] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [MRNA] (ISOFORM 2), FUNCTION, VARIANTS ALA-200 AND ARG-444. Tissue: Placenta.
[3]	"The secreted protein discovery initiative (SPDI), a large-scale effort to identify novel human secreted and transmembrane proteins: a bioinformatics assessment." Clark H.F., Gurney A.L., Abaya E., Baker K., Baldwin D.T., Brush J., Chen J., Chow B., Chui C., Crowley C., Currell B., Deuel B., Dowd P., Eaton D., Foster J.S., Grimaldi C., Gu Q., Hass P.E. , Heldens S., Huang A., Kim H.S., Klimowski L., Jin Y., Johnson S., Lee J., Lewis L., Liao D., Mark M.R., Robbie E., Sanchez C., Schoenfeld J., Seshagiri S., Simmons L., Singh J., Smith V., Stinson J., Vagts A., Vandlen R.L., Watanabe C., Wieand D., Woods K., Xie M.-H., Yansura D.G., Yi S., Yu G., Yuan J., Zhang M., Zhang Z., Goddard A.D., Wood W.I., Godowski P.J., Gray A.M. Genome Res. 13:2265-2270(2003) [PubMed: 12975309] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA] (ISOFORM 1).
[4]	Totoki Y., Toyoda A., Takeda T., Sakaki Y., Tanaka A., Yokoyama S., Ohara O., Nagase T., Kikuno R.F. Submitted (MAR-2005) to the EMBL/GenBank/DDBJ databases Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA] (ISOFORM 1), VARIANT ALA-200. Tissue: Brain.
[5]	"The DNA sequence and biological annotation of human chromosome 1." Gregory S.G., Barlow K.F., McLay K.E., Kaul R., Swarbreck D., Dunham A., Scott C.E., Howe K.L., Woodfine K., Spencer C.C.A., Jones M.C., Gillson C., Searle S., Zhou Y., Kokocinski F., McDonald L., Evans R., Phillips K. , Atkinson A., Cooper R., Jones C., Hall R.E., Andrews T.D., Lloyd C., Ainscough R., Almeida J.P., Ambrose K.D., Anderson F., Andrew R.W., Ashwell R.I.S., Aubin K., Babbage A.K., Bagguley C.L., Bailey J., Beasley H., Bethel G., Bird C.P., Bray-Allen S., Brown J.Y., Brown A.J., Buckley D., Burton J., Bye J., Carder C., Chapman J.C., Clark S.Y., Clarke G., Clee C., Cobley V., Collier R.E., Corby N., Coville G.J., Davies J., Deadman R., Dunn M., Earthrowl M., Ellington A.G., Errington H., Frankish A., Frankland J., French L., Garner P., Garnett J., Gay L., Ghori M.R.J., Gibson R., Gilby L.M., Gillett W., Glithero R.J., Grafham D.V., Griffiths C., Griffiths-Jones S., Grocock R., Hammond S., Harrison E.S.I., Hart E., Haugen E., Heath P.D., Holmes S., Holt K., Howden P.J., Hunt A.R., Hunt S.E., Hunter G., Isherwood J., James R., Johnson C., Johnson D., Joy A., Kay M., Kershaw J.K., Kibukawa M., Kimberley A.M., King A., Knights A.J., Lad H., Laird G., Lawlor S., Leongamornlert D.A., Lloyd D.M., Loveland J., Lovell J., Lush M.J., Lyne R., Martin S., Mashreghi-Mohammadi M., Matthews L., Matthews N.S.W., McLaren S., Milne S., Mistry S., Moore M.J.F., Nickerson T., O'Dell C.N., Oliver K., Palmeiri A., Palmer S.A., Parker A., Patel D., Pearce A.V., Peck A.I., Pelan S., Phelps K., Phillimore B.J., Plumb R., Rajan J., Raymond C., Rouse G., Saenphimmachak C., Sehra H.K., Sheridan E., Shownkeen R., Sims S., Skuce C.D., Smith M., Steward C., Subramanian S., Sycamore N., Tracey A., Tromans A., Van Helmond Z., Wall M., Wallis J.M., White S., Whitehead S.L., Wilkinson J.E., Willey D.L., Williams H., Wilming L., Wray P.W., Wu Z., Coulson A., Vaudin M., Sulston J.E., Durbin R.M., Hubbard T., Wooster R., Dunham I., Carter N.P., McVean G., Ross M.T., Harrow J., Olson M.V., Beck S., Rogers J., Bentley D.R. Nature 441:315-321(2006) [PubMed: 16710414] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
[6]	"The status, quality, and expansion of the NIH full-length cDNA project: the Mammalian Gene Collection (MGC)." The MGC Project Team Genome Res. 14:2121-2127(2004) [PubMed: 15489334] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA] (ISOFORMS 1 AND 2), VARIANT ALA-200. Tissue: Chondrosarcoma and Kidney.
[7]	"Homology between egg white sulfhydryl oxidase and quiescin Q6 defines a new class of flavin-linked sulfhydryl oxidases." Hoober K.L., Glynn N.M., Burnside J., Coppock D.L., Thorpe C. J. Biol. Chem. 274:31759-31762(1999) [PubMed: 10542195] [Abstract] Cited for: INDUCTION, FUNCTION, MASS SPECTROMETRY.
[8]	"Regulation of the quiescence-induced genes: quiescin Q6, decorin, and ribosomal protein S29." Coppock D.L., Kopman C., Gudas J., Cina-Poppe D.A. Biochem. Biophys. Res. Commun. 269:604-610(2000) [PubMed: 10708601] [Abstract] Cited for: INDUCTION, FUNCTION, SUBCELLULAR LOCATION, TISSUE SPECIFICITY.
[9]	"The distribution and specificity of expression of quiescin Q6 (Q6) in Human tissues is associated with both endocrine and non-endocrine protein secretion." Turi G.K. Proc. Annu. Meet. Am. Assoc. Cancer Res. 42:397-397(2001) Cited for: TISSUE SPECIFICITY.
[10]	"Sulfhydryl oxidases: emerging catalysts of protein disulfide bond formation in eukaryotes." Thorpe C., Hoober K.L., Raje S., Glynn N.M., Burnside J., Turi G.K., Coppock D.L. Arch. Biochem. Biophys. 405:1-12(2002) [PubMed: 12176051] [Abstract] Cited for: FUNCTION, NOMENCLATURE, ALTERNATIVE SPLICING.
[11]	"Human plasma N-glycoproteome analysis by immunoaffinity subtraction, hydrazide chemistry, and mass spectrometry." Liu T., Qian W.-J., Gritsenko M.A., Camp D.G. II, Monroe M.E., Moore R.J., Smith R.D. J. Proteome Res. 4:2070-2080(2005) [PubMed: 16335952] [Abstract] Cited for: GLYCOSYLATION [LARGE SCALE ANALYSIS] AT ASN-130, MASS SPECTROMETRY. Tissue: Plasma.
[12]	"Intracellular catalysis of disulfide bond formation by the human sulfhydryl oxidase, QSOX1." Chakravarthi S., Jessop C.E., Willer M., Stirling C.J., Bulleid N.J. Biochem. J. 404:403-411(2007) [PubMed: 17331072] [Abstract] Cited for: FUNCTION, SUBCELLULAR LOCATION.
+	Additional computationally mapped references.

Cross-references

Sequence databases
EMBLGenBankDDBJ	U97276 mRNA. Translation: AAC09010.2. AF361868 mRNA. Translation: AAM00263.1. AY358941 mRNA. Translation: AAQ89300.1. AB209280 mRNA. Translation: BAD92517.1. Different initiation. AL390718 Genomic DNA. Translation: CAI14838.1. AL390718 Genomic DNA. Translation: CAI14839.1. BC017692 mRNA. Translation: AAH17692.1. BC100023 mRNA. Translation: AAI00024.1.
IPI	IPI00003590. IPI00465016.
RefSeq	NP_001004128.1. NP_002817.2.
UniGene	Hs.518374
3D structure databases
HSSP	HSSP built from PDB template 2TRX based on UniProtKB P00274.
ModBase	Search...
PTM databases
PhosphoSite	O00391.
Proteomic databases
PeptideAtlas	O00391.
PRIDE	O00391.
Genome annotation databases
Ensembl	ENSG00000116260. Homo sapiens. [Contig view]
GeneID	5768.
KEGG	hsa:5768.
UCSC	uc001gny.1. human. uc001gnz.1. human.
Organism-specific databases
GeneCards	GC01P178391.
HGNC	HGNC:9756. QSOX1.
MIM	603120. gene.
PharmGKB	PA34097.
GenAtlas	Search...
Phylogenomic databases
HOVERGEN	O00391.
OMA	O00391. CAEETNS.
Enzyme and pathway databases
BRENDA	1.8.3.2. 247.
Gene expression databases
ArrayExpress	O00391.
Bgee	O00391.
CleanEx	HS_QSOX1.
GermOnline	ENSG00000116260. Homo sapiens.
Family and domain databases
InterPro	IPR017905. ERV/ALR_sulphydryl_oxidase. IPR006863. Evr1_Alr. IPR017936. Thioredoxin-like. IPR013766. Thioredoxin_domain. IPR012335. Thioredoxin_fold. [Graphical view]
Gene3D	G3DSA:1.20.120.310. Evr1_Alr. 1 hit. G3DSA:3.40.30.10. Thioredoxin_fold. 1 hit.
Pfam	PF04777. Evr1_Alr. 1 hit. PF00085. Thioredoxin. 1 hit. [Graphical view]
PROSITE	PS51324. ERV_ALR. 1 hit. PS51352. THIOREDOXIN_2. 1 hit. [Graphical view]
ProtoNet	Search...
Other Resources
NextBio	22434.
SOURCE	Search...

Entry information

Entry name

QSOX1_HUMAN

Accession

Primary (citable) accession number: O00391
Secondary accession number(s): Q59G29 , Q5T2X0, Q8TDL6, Q8WVP4

Entry history

Integrated into UniProtKB/Swiss-Prot:	September 19, 2006
Last sequence update:	June 1, 2001
Last modified:	July 7, 2009
This is version 75 of the entry and version 3 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation project

HPI (Human Proteome Initiative)