Gene Ontology annotation based on Enzyme Commission mapping
Annotation inferences using phylogenetic trees
Gene Ontology annotation based on UniPathway vocabulary mapping
Gene Ontology annotation based on UniProtKB/Swiss-Prot Subcellular Location vocabulary mapping, accompanied by conservative changes to GO terms applied by UniProt
Electronic Gene Ontology annotations created by ARBA machine learning models
Combined Automated Annotation using Multiple IEA Methods
Androgen metabolism via 17beta-hydroxysteroid dehydrogenase type 3 in mammalian and non-mammalian vertebrates: comparison of the human and the zebrafish enzyme.
-
Recombinant zebrafish Hsd17b3 reduces androstenedione to testosterone using NADPH.
"The zebrafish enzyme in vitro effectively catalyzed the conversion of androstenedione to testosterone by use of NADPH as cofactor."
-
Zebrafish Hsd17b3 also reduces DHEA and epiandrosterone at C-17 but, unlike the human enzyme, not androsterone or androstanedione.
"Among further tested androgens epiandrosterone and dehydroepiandrosterone were accepted as substrates and reduced at C-17 by the human and the zebrafish enzyme. Androsterone and androstanedione though, were only substrates of human 17beta-HSD type 3, not the zebrafish enzyme."
-
Both human and zebrafish enzymes reduce 11-ketoandrostenedione and 11beta-hydroxyandrostenedione at C-17, i.e. toward 11-ketotestosterone.
"we found that both enzymes can reduce 11-ketoandrostenedione as well as 11beta-hydroxyandrostenedione at C-17 to the respective testosterone forms."
-
Zebrafish Hsd17b3 localizes to the endoplasmic reticulum.
"At the subcellular level, both human and zebrafish 17beta-HSD type 3 localize to the endoplasmic reticulum."
-
Expression is not testis-restricted; it is embryonic (sphere to 84 hpf) and sexually dimorphic in adults, highest in male liver and in ovary.
"Expression was also detected in various tissues of both male and female adults, but displayed sexual dimorphism. Interestingly, expression was not highest in male testis but in male liver. In female adults, strongest expression was observed in ovaries."
Absence of 11-keto reduction of cortisone and 11-ketotestosterone in the model organism zebrafish.
-
Zebrafish androgen and glucocorticoid metabolism was compared with human using recombinant enzymes and microsomes; UniProt cites this paper as additional evidence for Hsd17b3 EC 1.1.1.64 activity and for reduction of 11-ketoandrostenedione.
"We compared glucocorticoid and androgen metabolism between human and zebrafish using recombinant enzymes, microsomal preparations and zebrafish larvae."
-
Zebrafish lack 11-ketosteroid reductase activity; 11-ketotestosterone production is sustained, with Hsd11b2 generating the main fish androgen 11KT.
"Additionally, a dual-role of 11β-HSD2 by inactivating glucocorticoids and generating the main fish androgen 11KT was supported."
UniProtKB entry Q6QA32 for Danio rerio hsd17b3
-
Curated function is NADPH-dependent reduction of 17-oxosteroids to 17beta-hydroxysteroids, favoring androstenedione to testosterone.
"FUNCTION: Catalyzes the conversion of 17-oxosteroids to 17beta-hydroxysteroids in the presence of NADPH (PubMed:16216911, PubMed:27927697). Favors the reduction of androstenedione to testosterone (PubMed:16216911, PubMed:27927697)."
-
Curated subcellular location is the endoplasmic reticulum, with predicted single-pass membrane topology.
"SUBCELLULAR LOCATION: Endoplasmic reticulum {ECO:0000269|PubMed:16216911}. Membrane {ECO:0000255}; Single-pass membrane protein {ECO:0000255}."
-
The enzyme is placed in the testosterone biosynthesis pathway.
"PATHWAY: Hormone biosynthesis; testosterone biosynthesis."
Falcon (Edison) deep research report for Danio rerio hsd17b3 (Q6QA32)
-
Unlike testis-restricted mammalian HSD17B3, zebrafish hsd17b3 is broadly expressed across adult tissues (dominant in testis, liver, ovary), suggesting a more somatic expression pattern.
"Zebrafish hsd17b3 expression is reported across **multiple adult tissues**, with summarized dominant sites including **testis, liver, and ovary**, and additional detection reported in **skin, muscle, spleen, intestine, and eyes**."
-
In vivo developmental contribution may be stage-dependent: hsd17b3 expression is low or undetected in juvenile zebrafish gonads (19/30 dpf), implying another Hsd17b enzyme may supply 17beta-HSD activity at early stages.
"They report that **hsd17b3 expression is low** at both 19 and 30 dpf and that they **did not detect hsd17b3** in ZZ NA gonads at 30 dpf."
-
Zebrafish lacks an HSD17B5 ortholog, raising the possibility that zebrafish Hsd17b3 covers roles distributed among multiple paralogs in mammals.
"notes that zebrafish lacks an HSD17B5 ortholog, raising the possibility that zebrafish Hsd17b3 may cover functional roles that in mammals are distributed differently among paralogs."