Q8AVI9 (PORED_XENLA) Reviewed, UniProtKB/Swiss-Prot

Names and origin

Protein names

Recommended name:
Polyprenol reductase
EC=1.3.1.94

Alternative name(s):
3-oxo-5-alpha-steroid 4-dehydrogenase 3
EC=1.3.1.22
Steroid 5-alpha-reductase 3
Short name=S5AR 3
Short name=SR type 3

Gene names

Name:

srd5a3

Organism

Xenopus laevis (African clawed frog)

Taxonomic identifier

8355 [NCBI]

Taxonomic lineage

cellular organisms › Eukaryota › Opisthokonta › Metazoa › Eumetazoa › Bilateria › Deuterostomia › Chordata › Craniata › Vertebrata › Gnathostomata › Teleostomi › Euteleostomi › Sarcopterygii › Tetrapoda › Amphibia › Batrachia › Anura › Pipoidea › Pipidae › Xenopodinae › Xenopus › Xenopus

Protein attributes

Sequence length	319 AA.
Sequence status	Complete.
Protein existence	Evidence at transcript level

General annotation (Comments)

Function	Plays a key role in early steps of protein N-linked glycosylation by being required for the conversion of polyprenol into dolichol. Dolichols are required for the synthesis of dolichol-linked monosaccharides and the oligosaccharide precursor used for N-glycosylation. Acts as a polyprenol reductase that promotes the reduction of the alpha-isoprene unit of polyprenols into dolichols in a NADP-dependent mechanism. Also able to convert testosterone (T) into 5-alpha-dihydrotestosterone (DHT) By similarity.
Catalytic activity	Ditrans,polycis-dolichol + NADP+ = ditrans,polycis-polyprenol + NADPH. A 3-oxo-5-alpha-steroid + NADP+ = a 3-oxo-Delta(4)-steroid + NADPH.
Pathway	Protein modification; protein glycosylation.
Subcellular location	Endoplasmic reticulum membrane; Multi-pass membrane protein By similarity.
Sequence similarities	Belongs to the steroid 5-alpha reductase family. Polyprenol reductase subfamily.

Ontologies

Keywords
Cellular component	Endoplasmic reticulum Membrane
Domain	Transmembrane Transmembrane helix
Ligand	NADP
Molecular function	Oxidoreductase
Gene Ontology (GO)
Biological_process	dolichol metabolic process Inferred from sequence or structural similarity. Source: UniProtKB dolichol-linked oligosaccharide biosynthetic process Inferred from sequence or structural similarity. Source: UniProtKB polyprenol catabolic process Inferred from sequence or structural similarity. Source: UniProtKB protein glycosylation Inferred from electronic annotation. Source: UniProtKB-UniPathway
Cellular_component	endoplasmic reticulum Inferred from sequence or structural similarity. Source: UniProtKB endoplasmic reticulum membrane Inferred from electronic annotation. Source: UniProtKB-SubCell integral to membrane Inferred from electronic annotation. Source: UniProtKB-KW
Molecular_function	3-oxo-5-alpha-steroid 4-dehydrogenase activity Inferred from sequence or structural similarity. Source: UniProtKB cholestenone 5-alpha-reductase activity Inferred from electronic annotation. Source: EC oxidoreductase activity, acting on the CH-CH group of donors, NAD or NADP as acceptor Inferred from sequence or structural similarity. Source: UniProtKB
Complete GO annotation...

Sequence annotation (Features)

	Feature key	Position(s)	Length	Description	Graphical view	Feature identifier
Molecule processing
	Chain	1 – 319	319	Polyprenol reductase		PRO_0000317705
Regions
	Topological domain	1 – 12	12	Cytoplasmic Potential
	Transmembrane	13 – 33	21	Helical; Potential
	Topological domain	34 – 79	46	Lumenal Potential
	Transmembrane	80 – 100	21	Helical; Potential
	Topological domain	101 – 122	22	Cytoplasmic Potential
	Transmembrane	123 – 143	21	Helical; Potential
	Topological domain	144 – 158	15	Lumenal Potential
	Transmembrane	159 – 179	21	Helical; Potential
	Topological domain	180 – 195	16	Cytoplasmic Potential
	Transmembrane	196 – 216	21	Helical; Potential
	Topological domain	217 – 266	50	Lumenal Potential
	Transmembrane	267 – 287	21	Helical; Potential
	Topological domain	288 – 319	32	Cytoplasmic Potential

Sequences

	Sequence		Length	Mass (Da)
	Q8AVI9 [UniParc]. Last modified March 1, 2003. Version 1. Checksum: 5163DCD07643B1DB	FASTA	319	36,591
	10 20 30 40 50 60 MQLVQLLPPG VSLLALVWLA VDAAFLTALL LYLQRGCDSG RSLLCSVFQD LIRYGKTKSG 70 80 90 100 110 120 LRRPSWLQWF DIPKRCFWHF YFVSLVWNGF LLWILLHLLL QSVPVPEWLQ AVLQFLCAGS 130 140 150 160 170 180 EPQVLGGELS VVLAFSLLWL HSLRRLLECL FVSIFSNGVI HFVQYCFGLG YYILIGFTIL 190 200 210 220 230 240 GYCPLDRRTA VSLDDLLMQG NWYHILGLTL YVWASLHQYT CHCILADLRK SASGAIINLK 250 260 270 280 290 300 HAVPTGDWFE KVSCPHYFAE LLIYLSIAVV FGLLNTIWWL VVLYVLLSQA LAAVLCHEFY 310 HEKFDSYPIH RKAFIPLIF

References

[1]	NIH - Xenopus Gene Collection (XGC) project Submitted (JAN-2003) to the EMBL/GenBank/DDBJ databases Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA]. Tissue: Embryo.

Cross-references

Sequence databases
EMBL GenBank DDBJ	BC042255 mRNA. Translation: AAH42255.1.
RefSeq	NP_001079436.1. NM_001085967.1.
UniGene	Xl.15326.
3D structure databases
ModBase	Search...
Protocols and materials databases
StructuralBiologyKnowledgebase	Search...
Genome annotation databases
GeneID	379123.
KEGG	xla:379123.
Organism-specific databases
CTD	79644.
Xenbase	XB-GENE-985517. srd5a3.
Phylogenomic databases
HOVERGEN	HBG057797.
KO	K12345.
Enzyme and pathway databases
UniPathway	UPA00378.
Family and domain databases
InterPro	IPR001104. 3-oxo-5_a-steroid_4-DH_C. [Graphical view]
Pfam	PF02544. Steroid_dh. 1 hit. [Graphical view]
PROSITE	PS50244. S5A_REDUCTASE. 1 hit. [Graphical view]
ProtoNet	Search...

Entry information

Entry name

PORED_XENLA

Accession

Primary (citable) accession number: Q8AVI9

Entry history

Integrated into UniProtKB/Swiss-Prot:	February 5, 2008
Last sequence update:	March 1, 2003
Last modified:	February 6, 2013
This is version 51 of the entry and version 1 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation program

Chordata Protein Annotation Program