Names & Taxonomy
- Uniprot ID:
- Q9H8P0
- Entry Name:
- PORED_HUMAN
- Status:
- reviewed
- Protein Names:
- Polyprenol 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)
- Gene Names:
- SRD5A3 SRD5A2L
- Gene Names Primary:
- SRD5A3
- Organism:
- Homo sapiens (Human)
Structure
- Length:
- 318
- Sequence:
- MAPWAEAEHSALNPLRAVWLTLTAAFLLTLLLQLLPPGLLPGCAIFQDLIRYGKTKCGEPSRPAACRAFDVPKRYFSHFYIISVLWNGFLLWCLTQSLFLGAPFPSWLHGLLRILGAAQFQGGELALSAFLVLVFLWLHSLRRLFECLYVSVFSNVMIHVVQYCFGLVYYVLVGLTVLSQVPMDGRNAYITGKNLLMQARWFHILGMMMFIWSSAHQYKCHVILGNLRKNKAGVVIHCNHRIPFGDWFEYVSSPNYLAELMIYVSMAVTFGFHNLTWWLVVTNVFFNQALSAFLSHQFYKSKFVSYPKHRKAFLPFLF
- Proteomes:
- UP000005640
Subcellular location
- Subcellular Location:
- Endoplasmic reticulum membrane
Function
- 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).
- Pathway:
- Protein modification; protein glycosylation.
- Catalytic Activity:
- Ditrans,polycis-dolichol + NADP(+) = ditrans,polycis-polyprenol + NADPH.; A 3-oxo-5-alpha-steroid + NADP(+) = a 3-oxo-Delta(4)-steroid + NADPH.
- Cross Reference Drug Bank:
- DB00421
- Gene Ontology Go:
- endoplasmic reticulum
endoplasmic reticulum membrane
integral component of membrane
3-oxo-5-alpha-steroid 4-dehydrogenase activity
cholestenone 5-alpha-reductase activity
oxidoreductase activity, acting on the CH-CH group of donors, NAD or NADP as acceptor
androgen biosynthetic process
cellular protein metabolic process
dolichol metabolic process
dolichol-linked oligosaccharide biosynthetic process
dolichyl diphosphate biosynthetic process
polyprenol catabolic process
post-translational protein modification
protein N-linked glycosylation via asparagine
small molecule metabolic process
steroid metabolic process - Gene Ontology Biological Process:
- androgen biosynthetic process
cellular protein metabolic process
dolichol-linked oligosaccharide biosynthetic process
dolichol metabolic process
dolichyl diphosphate biosynthetic process
polyprenol catabolic process
post-translational protein modification
protein N-linked glycosylation via asparagine
small molecule metabolic process
steroid metabolic process - Gene Ontology Molecular Function:
- 3-oxo-5-alpha-steroid 4-dehydrogenase activity
cholestenone 5-alpha-reductase activity
oxidoreductase activity, acting on the CH-CH group of donors, NAD or NADP as acceptor - Gene Ontology Cellular Component:
- endoplasmic reticulum
endoplasmic reticulum membrane
integral component of membrane - Keywords:
- Cataract
Complete proteome
Congenital disorder of glycosylation
Endoplasmic reticulum
Membrane
Mental retardation
NADP
Oxidoreductase
Reference proteome
Transmembrane
Transmembrane helix