Q04828 (AK1C1_HUMAN) Reviewed, UniProtKB/Swiss-Prot

Names and origin

Protein names

Recommended name:
Aldo-keto reductase family 1 member C1
EC=1.1.1.-

Alternative name(s):
20-alpha-hydroxysteroid dehydrogenase
Short name=20-alpha-HSD
EC=1.1.1.149
Chlordecone reductase homolog HAKRC
Dihydrodiol dehydrogenase 1/2
Short name=DD1/DD2
High-affinity hepatic bile acid-binding protein
Short name=HBAB
Indanol dehydrogenase
EC=1.1.1.112
Trans-1,2-dihydrobenzene-1,2-diol dehydrogenase
EC=1.3.1.20

Gene names

Name:	AKR1C1
Synonyms:	DDH, DDH1

Organism

Homo sapiens (Human) [Reference proteome]

Taxonomic identifier

9606 [NCBI]

Taxonomic lineage

cellular organisms › Eukaryota › Opisthokonta › Metazoa › Eumetazoa › Bilateria › Deuterostomia › Chordata › Craniata › Vertebrata › Gnathostomata › Teleostomi › Euteleostomi › Sarcopterygii › Tetrapoda › Amniota › Mammalia › Theria › Eutheria › Euarchontoglires › Primates › Haplorrhini › Simiiformes › Catarrhini › Hominoidea › Hominidae › Homininae › Homo

Protein attributes

Sequence length	323 AA.
Sequence status	Complete.
Protein existence	Evidence at protein level

General annotation (Comments)

Function	Converts progesterone to its inactive form, 20-alpha-dihydroxyprogesterone (20-alpha-OHP). In the liver and intestine, may have a role in the transport of bile. May have a role in monitoring the intrahepatic bile acid concentration. Has a low bile-binding ability. May play a role in myelin formation. Ref.6 Ref.11
Catalytic activity	17-alpha,20-alpha-dihydroxypregn-4-en-3-one + NAD(P)+ = 17-alpha-hydroxyprogesterone + NAD(P)H. Ref.6 Ref.11 Trans-1,2-dihydrobenzene-1,2-diol + NADP+ = catechol + NADPH. Ref.6 Ref.11 Indan-1-ol + NAD(P)+ = indanone + NAD(P)H. Ref.6 Ref.11
Enzyme regulation	Inhibited by hexestrol with an IC50 of 9.5 µM, 1,10-phenanthroline with an IC50 of 55 µM, 1,7-phenanthroline with an IC50 of 72 µM, flufenamic acid with an IC50 of 6.0 µM, indomethacin with an IC50 of 140 µM, ibuprofen with an IC50 of 950 µM, lithocholic acid with an IC50 of 25 µM, ursodeoxycholic acid with an IC50 of 340 µM and chenodeoxycholic acid with an IC50 of 570 µM. Ref.11
Subunit structure	Monomer.
Subcellular location	Cytoplasm.
Tissue specificity	Expressed in all tissues tested including liver, prostate, testis, adrenal gland, brain, uterus, mammary gland and keratinocytes. Highest levels found in liver, mammary gland and brain. Ref.6
Sequence similarities	Belongs to the aldo/keto reductase family.
Biophysicochemical properties	Kinetic parameters: KM=5 µM for (s)-tetralol Ref.6 Ref.11 KM=38 µM for (s)-indan-1-ol KM=580 µM for benzene dihydrodiol KM=3 µM for 5-beta-pregnane-3-alpha,20-alpha-diol KM=3 µM for 5-beta-pregnan-20-alpha-ol-3-one KM=12 µM for 4-pregnen-20-alpha-ol-3-one KM=133 µM for 9-alpha,11-beta-PGF2 KM=2 µM for 5-beta-pregnan-3-alpha-ol-20-one KM=1 µM for 5-beta-androstane-3,17-dione KM=12 µM for PGD2 KM=0.6 µM for 20-alpha-hydroxyprogesterone (with NADH)

Ontologies

Keywords
Cellular component	Cytoplasm
Coding sequence diversity	Polymorphism
Ligand	NADP
Molecular function	Oxidoreductase
Technical term	3D-structure Complete proteome Direct protein sequencing Reference proteome
Gene Ontology (GO)
Biological_process	bile acid and bile salt transport Traceable author statement Ref.1. Source: UniProtKB bile acid metabolic process Inferred from direct assay Ref.1. Source: UniProtKB cellular response to jasmonic acid stimulus Inferred from direct assay PubMed 19487289. Source: UniProtKB cholesterol homeostasis Traceable author statement Ref.1. Source: UniProtKB daunorubicin metabolic process Inferred from mutant phenotype PubMed 20837989. Source: UniProtKB doxorubicin metabolic process Inferred from mutant phenotype PubMed 20837989. Source: UniProtKB intestinal cholesterol absorption Traceable author statement Ref.1. Source: UniProtKB phototransduction, visible light Traceable author statement. Source: Reactome progesterone metabolic process Inferred from direct assay PubMed 21232532. Source: UniProtKB protein homooligomerization Inferred from direct assay Ref.1. Source: UniProtKB response to organophosphorus Inferred from expression pattern PubMed 16079077. Source: UniProtKB retinal metabolic process Inferred from direct assay PubMed 21851338. Source: UniProtKB xenobiotic metabolic process Non-traceable author statement Ref.1. Source: UniProtKB
Cellular_component	cytosol Inferred from direct assay Ref.1. Source: UniProtKB
Molecular_function	17-alpha,20-alpha-dihydroxypregn-4-en-3-one dehydrogenase activity Inferred from electronic annotation. Source: EC alditol:NADP+ 1-oxidoreductase activity Inferred from direct assay PubMed 21232532. Source: UniProtKB androsterone dehydrogenase (B-specific) activity Inferred from direct assay Ref.1. Source: UniProtKB bile acid binding Inferred from direct assay Ref.1. Source: UniProtKB indanol dehydrogenase activity Inferred from electronic annotation. Source: EC ketosteroid monooxygenase activity Inferred from direct assay PubMed 21232532. Source: UniProtKB oxidoreductase activity, acting on NAD(P)H, quinone or similar compound as acceptor Inferred from direct assay PubMed 19442656PubMed 20837989. Source: UniProtKB phenanthrene 9,10-monooxygenase activity Inferred from direct assay PubMed 21851338. Source: UniProtKB trans-1,2-dihydrobenzene-1,2-diol dehydrogenase activity Inferred from direct assay Ref.1. Source: UniProtKB
Complete GO annotation...

Sequence annotation (Features)

Feature key

Position(s)

Length

Description

Graphical view

Feature identifier

Molecule processing

Chain

1 – 323

323

Aldo-keto reductase family 1 member C1

PRO_0000124633

Regions

Nucleotide binding

13 – 22

10

NADP Potential

Nucleotide binding

217 – 280

64

NADP By similarity

Sites

Active site

55

1

Proton donor By similarity

Binding site

117

1

Substrate By similarity

Binding site

304

1

Progesterone

Site

54

1

Important for substrate specificity By similarity

Site

84

1

Lowers pKa of active site Tyr By similarity

Site

222

1

May be involved in the mediating step between the transformation of progesterone and the release of the cofactor

Natural variations

Natural variant

170

1

R → H.
Corresponds to variant rs17295755 [ dbSNP | Ensembl ].

VAR_048214

Natural variant

172

1

Q → L.
Corresponds to variant rs17354444 [ dbSNP | Ensembl ].

VAR_048215

Experimental info

Mutagenesis

127

1

E → D: 30-fold decrease in k(cat)/K(m) value for progesterone reduction; no effect on the K(m) value. Ref.13

Mutagenesis

222

1

H → I: Marked decrease in k(cat)/K(m) value for progesterone; 24-fold decrease for progesterone reduction; 18-fold decrease for 20alpha-OHProg oxidation. 95-fold decrease in K(m) value for NADPH. Ref.13

Mutagenesis

222

1

H → S: Marked decrease in k(cat)/K(m) value for progesterone; 10-fold decrease for progesterone reduction; 3-fold decrease for 20alpha-OHProg oxidation. 10-fold decrease in K(m) value for NADPH. Ref.13

Mutagenesis

304

1

R → L: 70-fold decrease in progesterone reduction. No effect on DHT reduction. Ref.13

Mutagenesis

305

1

Y → F: No effect on progesterone reduction. Ref.13

Mutagenesis

307

1

T → V: No effect on progesterone reduction. Ref.13

Mutagenesis

309

1

D → V: No effect on progesterone reduction. Ref.13

Sequence conflict

3

1

S → A no nucleotide entry Ref.4

Sequence conflict

95

1

V → D no nucleotide entry Ref.4

Sequence conflict

95

1

V → D in AAD14012. Ref.10

Sequence conflict

158

1

G → E no nucleotide entry Ref.4

Sequence conflict

158

1

G → E in AAD14012. Ref.10

Sequence conflict

171 – 172

2

RQ → ST no nucleotide entry Ref.4

Sequence conflict

171 – 172

2

RQ → ST in AAD14012. Ref.10

Sequence conflict

183 – 184

2

KY → QV no nucleotide entry Ref.4

Sequence conflict

183 – 184

2

KY → QV in AAD14012. Ref.10

Sequence conflict

222

1

H → L no nucleotide entry Ref.4

Sequence conflict

222

1

H → L in AAD14012. Ref.10

Sequence conflict

319

1

F → I no nucleotide entry Ref.4

Sequence conflict

319

1

F → I in AAD14012. Ref.10

Secondary structure

1

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323

Helix Strand Turn

Details...

Beta strand

7 – 9

3

Beta strand

15 – 22

8

Helix

33 – 44

12

Beta strand

48 – 50

3

Helix

53 – 55

3

Helix

58 – 70

13

Helix

76 – 78

3

Beta strand

80 – 85

6

Helix

87 – 89

3

Helix

92 – 106

15

Beta strand

111 – 116

6

Beta strand

124 – 126

3

Helix

144 – 156

13

Beta strand

159 – 167

9

Helix

170 – 177

8

Beta strand

187 – 192

6

Beta strand

194 – 197

4

Helix

200 – 208

9

Beta strand

212 – 217

6

Turn

225 – 227

3

Helix

235 – 237

3

Helix

239 – 248

10

Helix

252 – 262

11

Beta strand

266 – 270

5

Helix

274 – 280

7

Helix

281 – 285

5

Helix

290 – 297

8

Helix

309 – 311

3

Sequences

	Sequence		Length	Mass (Da)
	Q04828 [UniParc]. Last modified October 1, 1993. Version 1. Checksum: 9CB215478FBD29D5	FASTA	323	36,788
	10 20 30 40 50 60 MDSKYQCVKL NDGHFMPVLG FGTYAPAEVP KSKALEATKL AIEAGFRHID SAHLYNNEEQ 70 80 90 100 110 120 VGLAIRSKIA DGSVKREDIF YTSKLWCNSH RPELVRPALE RSLKNLQLDY VDLYLIHFPV 130 140 150 160 170 180 SVKPGEEVIP KDENGKILFD TVDLCATWEA VEKCKDAGLA KSIGVSNFNR RQLEMILNKP 190 200 210 220 230 240 GLKYKPVCNQ VECHPYFNQR KLLDFCKSKD IVLVAYSALG SHREEPWVDP NSPVLLEDPV 250 260 270 280 290 300 LCALAKKHKR TPALIALRYQ LQRGVVVLAK SYNEQRIRQN VQVFEFQLTS EEMKAIDGLN 310 320 RNVRYLTLDI FAGPPNYPFS DEY

References

	« Hide 'large scale' referencesShow 'large scale' references »
[1]	"cDNA cloning and expression of the human hepatic bile acid-binding protein. A member of the monomeric reductase gene family." Stolz A., Hammond L., Lou H., Takikawa H., Ronk M., Shively J.E. J. Biol. Chem. 268:10448-10457(1993) [PubMed] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [MRNA]. Tissue: Liver.
[2]	"Genomic organization and chromosomal localization of a novel human hepatic dihydrodiol dehydrogenase with high affinity bile acid binding." Lou H., Hammond L., Sharma V., Sparkes R.S., Lusis A.J., Stolz A. J. Biol. Chem. 269:8416-8422(1994) [PubMed] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA]. Tissue: Blood.
[3]	"Regulation of human dihydrodiol dehydrogenase by Michael acceptor xenobiotics." Ciaccio P.J., Jaiswal A.K., Tew K.D. J. Biol. Chem. 269:15558-15562(1994) [PubMed] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [MRNA]. Tissue: Colon.
[4]	"Distribution of 3 alpha-hydroxysteroid dehydrogenase in rat brain and molecular cloning of multiple cDNAs encoding structurally related proteins in humans." Khanna M., Qin K.-N., Cheng K.-C. J. Steroid Biochem. Mol. Biol. 53:41-46(1995) [PubMed] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [MRNA]. Tissue: Liver.
[5]	"Close kinship of human 20alpha-hydroxysteroid dehydrogenase gene with three aldo-keto reductase genes." Nishizawa M., Nakajima T., Yasuda K., Kanzaki H., Sasaguri Y., Watanabe K., Ito S. Genes Cells 5:111-125(2000) [PubMed] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [MRNA]. Tissue: Liver.
[6]	"Characterization of a human 20alpha-hydroxysteroid dehydrogenase." Zhang Y., Dufort I., Rheault P., Luu-The V. J. Mol. Endocrinol. 25:221-228(2000) [PubMed] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [MRNA], FUNCTION, CATALYTIC ACTIVITY, BIOPHYSICOCHEMICAL PROPERTIES, TISSUE SPECIFICITY. Tissue: Skin fibroblast.
[7]	"Cloning of human full-length CDSs in BD Creator(TM) system donor vector." Kalnine N., Chen X., Rolfs A., Halleck A., Hines L., Eisenstein S., Koundinya M., Raphael J., Moreira D., Kelley T., LaBaer J., Lin Y., Phelan M., Farmer A. Submitted (MAY-2003) to the EMBL/GenBank/DDBJ databases Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA].
[8]	"The DNA sequence and comparative analysis of human chromosome 10." Deloukas P., Earthrowl M.E., Grafham D.V., Rubenfield M., French L., Steward C.A., Sims S.K., Jones M.C., Searle S., Scott C., Howe K., Hunt S.E., Andrews T.D., Gilbert J.G.R., Swarbreck D., Ashurst J.L., Taylor A., Battles J. , Bird C.P., Ainscough R., Almeida J.P., Ashwell R.I.S., Ambrose K.D., Babbage A.K., Bagguley C.L., Bailey J., Banerjee R., Bates K., Beasley H., Bray-Allen S., Brown A.J., Brown J.Y., Burford D.C., Burrill W., Burton J., Cahill P., Camire D., Carter N.P., Chapman J.C., Clark S.Y., Clarke G., Clee C.M., Clegg S., Corby N., Coulson A., Dhami P., Dutta I., Dunn M., Faulkner L., Frankish A., Frankland J.A., Garner P., Garnett J., Gribble S., Griffiths C., Grocock R., Gustafson E., Hammond S., Harley J.L., Hart E., Heath P.D., Ho T.P., Hopkins B., Horne J., Howden P.J., Huckle E., Hynds C., Johnson C., Johnson D., Kana A., Kay M., Kimberley A.M., Kershaw J.K., Kokkinaki M., Laird G.K., Lawlor S., Lee H.M., Leongamornlert D.A., Laird G., Lloyd C., Lloyd D.M., Loveland J., Lovell J., McLaren S., McLay K.E., McMurray A., Mashreghi-Mohammadi M., Matthews L., Milne S., Nickerson T., Nguyen M., Overton-Larty E., Palmer S.A., Pearce A.V., Peck A.I., Pelan S., Phillimore B., Porter K., Rice C.M., Rogosin A., Ross M.T., Sarafidou T., Sehra H.K., Shownkeen R., Skuce C.D., Smith M., Standring L., Sycamore N., Tester J., Thorpe A., Torcasso W., Tracey A., Tromans A., Tsolas J., Wall M., Walsh J., Wang H., Weinstock K., West A.P., Willey D.L., Whitehead S.L., Wilming L., Wray P.W., Young L., Chen Y., Lovering R.C., Moschonas N.K., Siebert R., Fechtel K., Bentley D., Durbin R.M., Hubbard T., Doucette-Stamm L., Beck S., Smith D.R., Rogers J. Nature 429:375-381(2004) [PubMed] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
[9]	"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] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA]. Tissue: Lung and Testis.
[10]	"Molecular cloning of multiple cDNAs encoding human enzymes structurally related to 3 alpha-hydroxysteroid dehydrogenase." Qin K.-N., New M.I., Cheng K.-C. J. Steroid Biochem. Mol. Biol. 46:673-679(1993) [PubMed] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [MRNA] OF 4-323. Tissue: Liver.
[11]	"Relationship of human liver dihydrodiol dehydrogenases to hepatic bile-acid-binding protein and an oxidoreductase of human colon cells." Hara A., Matsuura K., Tamada Y., Sato K., Miyabe Y., Deyashiki Y., Ishida N. Biochem. J. 313:373-376(1996) [PubMed] [Europe PMC] [Abstract] Cited for: PROTEIN SEQUENCE OF 10-31; 40-61; 69-126; 137-153; 162-206; 209-230; 250-267; 271-289 AND 295-323, FUNCTION, CATALYTIC ACTIVITY, ENZYME REGULATION, BIOPHYSICOCHEMICAL PROPERTIES.
[12]	"Molecular cloning of two human liver 3 alpha-hydroxysteroid/dihydrodiol dehydrogenase isoenzymes that are identical with chlordecone reductase and bile-acid binder." Deyashiki Y., Ogasawara A., Nakayama T., Nakanishi M., Miyabe Y., Sato K., Hara A. Biochem. J. 299:545-552(1994) [PubMed] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [MRNA] OF 18-323, PROTEIN SEQUENCE OF 18-31; 105-131; 176-193 AND 271-294. Tissue: Liver.
[13]	"Human 20alpha-hydroxysteroid dehydrogenase: crystallographic and site-directed mutagenesis studies lead to the identification of an alternative binding site for C21-steroids." Couture J.-F., Legrand P., Cantin L., Luu-The V., Labrie F., Breton R. J. Mol. Biol. 331:593-604(2003) [PubMed] [Europe PMC] [Abstract] Cited for: X-RAY CRYSTALLOGRAPHY (1.6 ANGSTROMS) IN COMPLEX WITH NADP AND 20ALPHA-HYDROXY-PROGESTERONE, MUTAGENESIS OF GLU-127; HIS-222; ARG-304; TYR-305; THR-307 AND ASP-309.
+	Additional computationally mapped references.

Cross-references

Sequence databases

EMBL
GenBank
DDBJ

M86609 mRNA. Translation: AAB02880.1.
U05861 , U05853, U05854, U05855, U05857, U05858, U05859, U05860 Genomic DNA. Translation: AAA18115.1.
U05684 mRNA. Translation: AAA16227.1.
AB031083 mRNA. Translation: BAA92883.1.
AB032150 Genomic DNA. Translation: BAA92886.1.
BT007197 mRNA. Translation: AAP35861.1.
AL713867, AC091817 Genomic DNA. Translation: CAI16409.1.
BC015490 mRNA. Translation: AAH15490.1.
BC020216 mRNA. Translation: AAH20216.1.
BC040210 mRNA. Translation: AAH40210.1.
S68290 mRNA. Translation: AAD14012.1.
D26124 mRNA. Translation: BAA05121.1.

IPI

IPI00029733.

PIR

A53436.
I73675.
S59619.
S61515.

RefSeq

NP_001344.2. NM_001353.5.

UniGene

Hs.460260.

3D structure databases

PDBe
RCSB PDB
PDBj

Entry	Method	Resolution (Å)	Chain	Positions	PDBsum
1MRQ	X-ray	1.59	A	2-323	[»]
3C3U	X-ray	1.80	A	1-323	[»]
3GUG	X-ray	1.90	A	1-323	[»]
3NTY	X-ray	1.87	A	1-323	[»]

ProteinModelPortal

Q04828.

ModBase

Search...

Protein-protein interaction databases

IntAct

Q04828. 2 interactions.

MINT

MINT-5001209.

STRING

9606.ENSP00000370254.

PTM databases

PhosphoSite

Q04828.

Polymorphism databases

DMDM

416877.

Proteomic databases

PaxDb

Q04828.

PRIDE

Q04828.

Protocols and materials databases

DNASU

1645.

StructuralBiologyKnowledgebase

Search...

Genome annotation databases

Ensembl

ENST00000380872; ENSP00000370254; ENSG00000187134.
ENST00000434459; ENSP00000412248; ENSG00000187134.
ENST00000578362; ENSP00000462940; ENSG00000266592.
ENST00000582412; ENSP00000462966; ENSG00000266592.

GeneID

1645.

KEGG

hsa:1645.

UCSC

uc001iho.3. human.

Organism-specific databases

CTD

1645.

GeneCards

GC10P004995.

HGNC

HGNC:384. AKR1C1.

HPA

CAB010874.
CAB047303.

MIM

600449. gene.

neXtProt

NX_Q04828.

PharmGKB

PA24677.

GenAtlas

Search...

Phylogenomic databases

eggNOG

COG0656.

HOGENOM

HOG000250272.

HOVERGEN

HBG000020.

InParanoid

Q04828.

KO

K00089.
K00212.

OMA

DSGIARD.

OrthoDB

EOG4Q2DG2.

PhylomeDB

Q04828.

Enzyme and pathway databases

SABIO-RK

Q04828.

Gene expression databases

ArrayExpress

Q04828.

Bgee

Q04828.

CleanEx

HS_AKR1C1.

Genevestigator

Q04828.

GermOnline

ENSG00000187134. Homo sapiens.

Family and domain databases

Gene3D

3.20.20.100. 1 hit.

InterPro

IPR001395. Aldo/ket_red.
IPR018170. Aldo/ket_reductase_CS.
IPR020471. Aldo/keto_reductase_subgr.
IPR023210. NADP_OxRdtase_dom.
[Graphical view]

PANTHER

PTHR11732. PTHR11732. 1 hit.

Pfam

PF00248. Aldo_ket_red. 1 hit.
[Graphical view]

PIRSF

PIRSF000097. AKR. 1 hit.

PRINTS

PR00069. ALDKETRDTASE.

SUPFAM

SSF51430. Aldo/ket_red. 1 hit.

PROSITE

PS00798. ALDOKETO_REDUCTASE_1. 1 hit.
PS00062. ALDOKETO_REDUCTASE_2. 1 hit.
PS00063. ALDOKETO_REDUCTASE_3. 1 hit.
[Graphical view]

ProtoNet

Search...

Other

BindingDB

Q04828.

ChEMBL

CHEMBL5905.

DrugBank

DB00157. NADH.

EvolutionaryTrace

Q04828.

GenomeRNAi

1645.

NextBio

6768.

SOURCE

Search...

Entry information

Entry name

AK1C1_HUMAN

Accession

Primary (citable) accession number: Q04828
Secondary accession number(s): P52896 , Q5SR15, Q7M4N2, Q9UCX2

Entry history

Integrated into UniProtKB/Swiss-Prot:	October 1, 1993
Last sequence update:	October 1, 1993
Last modified:	May 29, 2013
This is version 143 of the entry and version 1 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation program

Chordata Protein Annotation Program

Disclaimer

Any medical or genetic information present in this entry is provided for research, educational and informational purposes only. It is not in any way intended to be used as a substitute for professional medical advice, diagnosis, treatment or care.