Protein: Polyprenal reductase (EC 1.3.1.94) (3-oxo-5-alpha-steroid 4-dehydrogenase 3) (EC 1.3.1.22) (Steroid 5-alpha-reductase 2-like) (Steroid 5-alpha-reductase 3) (S5AR 3) (SR type 3) (Q9H8P0)
Organism: Homo sapiens (Human)
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).
Subcellular location: Endoplasmic reticulum membrane {ECO:0000305|PubMed:20637498}; Multi-pass membrane protein {ECO:0000255}.
Sequence: MAPWAEAEHSALNPLRAVWLTLTAAFLLTLLLQLLPPGLLPGCAIFQDLIRYGKTKCGEPSRPAACRAFDVPKRYFSHFYIISVLWNGFLLWCLTQSLFLGAPFPSWLHGLLRILGAAQFQGGELALSAFLVLVFLWLHSLRRLFECLYVSVFSNVMIHVVQYCFGLVYYVLVGLTVLSQVPMDGRNAYITGKNLLMQARWFHILGMMMFIWSSAHQYKCHVILGNLRKNKAGVVIHCNHRIPFGDWFEYVSSPNYLAELMIYVSMAVTFGFHNLTWWLVVTNVFFNQALSAFLSHQFYKSKFVSYPKHRKAFLPFLF
InterPro domains: - IPR001104: 3-oxo-5-alpha-steroid 4-dehydrogenase, C-terminal (domain) [199-318]
- IPR039698: Polyprenal reductase (family) [12-318]
Interaction partners: - 3-oxo-5-alpha-steroid 4-dehydrogenase 1
- Dolichol kinase
- Aldo-keto reductase family 1 member C3
- Aldo-keto reductase family 1 member C4
- 3 beta-hydroxysteroid dehydrogenase/Delta 5-->4-isomerase type 2
- Aldo-keto reductase family 1 member C2
- Steroid 17-alpha-hydroxylase/17,20 lyase
- 3-oxo-5-alpha-steroid 4-dehydrogenase 2
- 17-beta-hydroxysteroid dehydrogenase type 2
- Aldo-keto reductase family 1 member C1
Gene Ontology annotations:
Molecular Function (MF): GO:0003674 (molecular function), GO:0005488 (binding), GO:0003824 (catalytic activity), GO:0005515 (protein binding), GO:0016491 (oxidoreductase activity), GO:0016627 (oxidoreductase activity, acting on the CH-CH group of donors), GO:0016628 (oxidoreductase activity, acting on the CH-CH group of donors, NAD or NADP as acceptor)
Biological Process (BP): GO:0008150 (biological process), GO:0008152 (metabolic process), GO:0009987 (cellular process), GO:0009058 (biosynthetic process), GO:0044237 (cellular metabolic process), GO:0044281 (small molecule metabolic process), GO:0071704 (organic substance metabolic process), GO:0044238 (primary metabolic process), GO:1901615 (organic hydroxy compound metabolic process), GO:1901576 (organic substance biosynthetic process), GO:0006629 (lipid metabolic process), GO:0044283 (small molecule biosynthetic process), GO:0120254 (olefinic compound metabolic process), GO:0006082 (organic acid metabolic process), GO:0044255 (cellular lipid metabolic process), GO:0006066 (alcohol metabolic process), GO:0044249 (cellular biosynthetic process), GO:0009687 (abscisic acid metabolic process), GO:0120255 (olefinic compound biosynthetic process), GO:0006720 (isoprenoid metabolic process), GO:1902644 (tertiary alcohol metabolic process), GO:0043436 (oxoacid metabolic process), GO:0016053 (organic acid biosynthetic process), GO:1901617 (organic hydroxy compound biosynthetic process), GO:0008299 (isoprenoid biosynthetic process), GO:0046165 (alcohol biosynthetic process), GO:0008610 (lipid biosynthetic process), GO:0019752 (carboxylic acid metabolic process), GO:1902645 (tertiary alcohol biosynthetic process), GO:0046394 (carboxylic acid biosynthetic process), GO:0006721 (terpenoid metabolic process), GO:0016114 (terpenoid biosynthetic process), GO:0043288 (apocarotenoid metabolic process), GO:0072330 (monocarboxylic acid biosynthetic process), GO:0016106 (sesquiterpenoid biosynthetic process), GO:0032787 (monocarboxylic acid metabolic process), GO:0006714 (sesquiterpenoid metabolic process)
Cellular Component (CC): GO:0005575 (cellular component), GO:0110165 (cellular anatomical entity), GO:0005622 (intracellular anatomical structure), GO:0043226 (organelle), GO:0016020 (membrane), GO:0005737 (cytoplasm), GO:0012505 (endomembrane system), GO:0031984 (organelle subcompartment), GO:0042175 (nuclear outer membrane-endoplasmic reticulum membrane network), GO:0031090 (organelle membrane), GO:0005783 (endoplasmic reticulum), GO:0043229 (intracellular organelle), GO:0043227 (membrane-bounded organelle), GO:0098827 (endoplasmic reticulum subcompartment), GO:0043231 (intracellular membrane-bounded organelle), GO:0005789 (endoplasmic reticulum membrane)