HSD3B7 (3 beta-hydroxysteroid dehydrogenase type 7; 3-beta-hydroxy-Delta(5)-C27-steroid oxidoreductase, EC 1.1.1.181) catalyzes the second committed step of bile-acid biosynthesis. Acting on the 7-alpha-hydroxylated sterols generated by CYP7A1/CYP7B1, it oxidizes the 3-beta-hydroxyl group and isomerizes the Delta5 double bond, converting 7-alpha-hydroxycholesterol (and related 7-alpha-hydroxy-oxysterols such as 7-alpha,25-, 7-alpha,26- and 7-alpha,24-triols) to the corresponding 3-oxo-Delta4 intermediates, e.g. 7-alpha-hydroxy-4-cholesten-3-one. A single such enzyme feeds all known pathways of bile-acid synthesis. It is specific for C27 bile-acid-precursor sterols and does not metabolize the C19/C21 steroids handled by the steroidogenic paralogs HSD3B1/HSD3B2 (with which it shares only ~34% identity). HSD3B7 is a multi-pass endoplasmic-reticulum-membrane (microsomal) enzyme expressed predominantly in liver. Loss-of-function mutations cause congenital bile acid synthesis defect type 1 (CBAS1), presenting as neonatal cholestasis, progressive liver disease and fat-soluble-vitamin malabsorption. By acting on the oxysterol 7-alpha,25-dihydroxycholesterol, the enzyme also contributes to turnover of the EBI2/GPR183 ligand that positions lymphocytes in lymphoid tissue.
| GO Term | Evidence | Action | Reason |
|---|---|---|---|
|
GO:0016616
oxidoreductase activity, acting on the CH-OH group of donors, NAD or NADP as acceptor
|
IBA
GO_REF:0000033 |
MODIFY |
Summary: Broad phylogenetically-inferred molecular-function term correctly placing HSD3B7 as an NAD(P)-dependent dehydrogenase acting on a CH-OH group. This is accurate but general; the specific activity is the 3-beta-hydroxy-Delta5-steroid dehydrogenase reaction on 7-alpha-hydroxylated C27 sterols.
Reason: The IBA term is correct at the family level but too general for a gene with a demonstrated specific catalytic activity. Retain the parent but propose the specific dehydrogenase terms already supported by experiment (GO:0003854, GO:0047016) as the core molecular function.
Propagation Review
Root cause:
TERM SCOPING PROBLEM
Failure modes:
GRANULARITY MISMATCH
Sources checked:
PANTHER:PTN000041225
· 3-beta-HSD family node (GO_Central IBA)
SUPPORTS TRANSFER
Family-level IBA correctly assigns the general NAD(P)-dependent CH-OH dehydrogenase activity, but HSD3B7 has a demonstrated more specific 3-beta-hydroxy-Delta5-C27-steroid dehydrogenase activity (PMID:11067870).
Proposed replacements:
3-beta-hydroxy-Delta5-steroid dehydrogenase (NAD+) activity
cholest-5-ene-3-beta,7-alpha-diol 3-beta-dehydrogenase activity
Supporting Evidence:
file:human/HSD3B7/HSD3B7-uniprot.txt
HSD VII is active
|
|
GO:0005789
endoplasmic reticulum membrane
|
IEA
GO_REF:0000044 |
ACCEPT |
Summary: HSD3B7 is a multi-pass endoplasmic reticulum membrane (microsomal) protein; this UniProt SubCellular-mapping IEA correctly captures the primary localization.
Reason: The ER membrane localization is directly stated in UniProt (SUBCELLULAR LOCATION) and consistent with the microsomal enzyme described in PMID:11067870 and with the two predicted transmembrane helices. This is a core aspect of the annotation.
Supporting Evidence:
file:human/HSD3B7/HSD3B7-uniprot.txt
Endoplasmic reticulum membrane; Multi-pass
|
|
GO:0006694
steroid biosynthetic process
|
IEA
GO_REF:0000120 |
MODIFY |
Summary: Broad biosynthetic-process term. HSD3B7 participates in steroid (sterol/bile-acid) biosynthesis, so the term is not wrong, but the specific and better-supported process is bile acid biosynthesis (GO:0006699).
Reason: Bile-acid precursors are C27 sterols and the enzyme is specific for the bile-acid pathway; the more informative process term GO:0006699 is preferred. The broad steroid-biosynthesis term is retained conceptually but should be specialized.
Proposed replacements:
bile acid biosynthetic process
Supporting Evidence:
file:human/HSD3B7/HSD3B7-uniprot.txt
Lipid metabolism; steroid biosynthesis
|
|
GO:0016616
oxidoreductase activity, acting on the CH-OH group of donors, NAD or NADP as acceptor
|
IEA
GO_REF:0000120 |
MODIFY |
Summary: Same broad dehydrogenase molecular-function term as the IBA annotation, here from InterPro/ARBA. Correct but general.
Reason: Correct family-level assignment (NAD(P)-dependent CH-OH oxidoreductase), but a more specific term is warranted given the demonstrated 3-beta-hydroxy-Delta5-steroid dehydrogenase activity. Propose the specific MF terms.
Proposed replacements:
3-beta-hydroxy-Delta5-steroid dehydrogenase (NAD+) activity
cholest-5-ene-3-beta,7-alpha-diol 3-beta-dehydrogenase activity
Supporting Evidence:
file:human/HSD3B7/HSD3B7-uniprot.txt
HSD VII is active
|
|
GO:0047016
cholest-5-ene-3-beta,7-alpha-diol 3-beta-dehydrogenase activity
|
IEA
GO_REF:0000120 |
ACCEPT |
Summary: Specific molecular-function term (EC 1.1.1.181) for the 3-beta-dehydrogenation of the 7-alpha-hydroxylated sterol cholest-5-ene-3-beta,7-alpha-diol (7-alpha-hydroxycholesterol). This is the demonstrated activity of HSD3B7 and is the core function; here inferred electronically but corroborated by experiment (PMID:11067870).
Reason: This is exactly the biochemically characterized activity of HSD3B7 acting on 7-alpha-hydroxycholesterol, matching the UniProt catalytic-activity entry (Rhea:11896, EC 1.1.1.181). Accept as a core molecular function.
Supporting Evidence:
PMID:11067870
active against four 7alpha-hydroxylated sterols
|
|
GO:0005515
protein binding
|
IPI
PMID:25416956 A proteome-scale map of the human interactome network. |
MARK AS OVER ANNOTATED |
Summary: Generic protein-binding annotation from a proteome-scale (HuRI/CCSB) binary interactome screen. The partner (SPRY2, O43597) is not part of a functionally characterized HSD3B7 complex, and the bare protein-binding term is uninformative about the enzyme's molecular function.
Reason: High-throughput interactome hits assigned only the uninformative GO:0005515 term. Per curation guidance, bare protein binding does not describe HSD3B7's catalytic function; this is retained as an over-annotation rather than removed, since the interaction data itself is experimental.
Supporting Evidence:
PMID:25416956
A proteome-scale map of the human interactome network
|
|
GO:0005515
protein binding
|
IPI
PMID:32296183 A reference map of the human binary protein interactome. |
MARK AS OVER ANNOTATED |
Summary: Generic protein-binding annotations from the HuRI binary interactome map, covering many heterogeneous partners (keratin-associated proteins, transcription factors, etc.). None represent a defined functional HSD3B7 complex, and the term is uninformative about molecular function.
Reason: These are large-scale yeast-two-hybrid/binary-screen hits annotated only to the bare GO:0005515 term. Not informative for HSD3B7's dehydrogenase function; marked as over-annotated per policy rather than removed.
Supporting Evidence:
PMID:32296183
A reference map of the human binary protein interactome
|
|
GO:0035754
B cell chemotaxis
|
IEA
GO_REF:0000107 |
KEEP AS NON CORE |
Summary: Biological-process annotation transferred by Ensembl Compara from the mouse ortholog (Q9EQC1), reflecting HSD3B7's role in degrading the oxysterol 7-alpha,25-dihydroxycholesterol, an EBI2/GPR183 ligand that positions B cells in lymphoid tissue.
Reason: This is a genuine but downstream/physiological consequence inferred from the mouse ortholog, not HSD3B7's core catalytic role in bile-acid synthesis. The human enzyme does act on 7-alpha,25-OHC in vitro (UniProt catalytic activity Rhea:47156), supporting relevance, but the process is peripheral and evidence is by-similarity; keep as non-core.
Supporting Evidence:
file:human/HSD3B7/HSD3B7-uniprot.txt
Plays a key role in cell positioning and
|
|
GO:0006699
bile acid biosynthetic process
|
TAS
Reactome:R-HSA-193368 |
ACCEPT |
Summary: HSD3B7 catalyzes the second step of the classic (neutral) bile-acid pathway via 7-alpha-hydroxycholesterol; Reactome annotates its participation in bile acid biosynthesis. This is a core biological process for HSD3B7.
Reason: Bile acid biosynthesis is the central, disease-defining role of HSD3B7, established biochemically and genetically (PMID:11067870). Accept as core.
Supporting Evidence:
PMID:11067870
a single C(27) 3beta-HSD enzyme can participate in all known pathways of bile acid synthesis
|
|
GO:0006699
bile acid biosynthetic process
|
TAS
Reactome:R-HSA-193775 |
ACCEPT |
Summary: Participation in bile-acid/bile-salt synthesis via the 24-hydroxycholesterol (acidic/alternative) branch; HSD3B7 performs the 3-beta-dehydrogenation/isomerization step on the 7-alpha-hydroxylated 24-hydroxy sterol. Core bile-acid process annotation.
Reason: Duplicate of the core bile-acid biosynthetic process annotation, from a different Reactome pathway branch. Correct and core; the enzyme acts across all bile-acid pathway branches.
Supporting Evidence:
PMID:11067870
a single C(27) 3beta-HSD enzyme can participate in all known pathways of bile acid synthesis
|
|
GO:0006699
bile acid biosynthetic process
|
TAS
Reactome:R-HSA-193807 |
ACCEPT |
Summary: Participation in bile-acid/bile-salt synthesis via the 27-hydroxycholesterol branch. HSD3B7 acts on the 7-alpha-hydroxylated 27-hydroxy sterol. Core bile-acid process annotation.
Reason: Duplicate of the core bile-acid biosynthetic process annotation from another Reactome branch. Consistent with the enzyme's broad substrate range across bile-acid pathways.
Supporting Evidence:
PMID:11067870
a single C(27) 3beta-HSD enzyme can participate in all known pathways of bile acid synthesis
|
|
GO:0003854
3-beta-hydroxy-Delta5-steroid dehydrogenase (NAD+) activity
|
TAS
Reactome:R-HSA-192097 |
ACCEPT |
Summary: Core molecular function - NAD+-dependent 3-beta-hydroxy-Delta5-steroid dehydrogenase (with associated isomerase activity). Reactome R-HSA-192097 describes HSD3B7 oxidizing/isomerizing 7-alpha-hydroxycholesterol to 4-cholesten-7-alpha-ol-3-one.
Reason: This is the defining catalytic activity of HSD3B7, supported by biochemistry (PMID:11067870) and by the Reactome reaction. Accept as a core molecular function.
Supporting Evidence:
Reactome:R-HSA-192097
catalyzed by HSD3B7 (3 beta-hydroxysteroid dehydrogenase type 7) in the endoplasmic reticulum membrane
|
|
GO:0003854
3-beta-hydroxy-Delta5-steroid dehydrogenase (NAD+) activity
|
TAS
Reactome:R-HSA-193789 |
ACCEPT |
Summary: Same core 3-beta-hydroxy-Delta5-steroid dehydrogenase activity, annotated from the Reactome reaction on cholest-5-ene-3beta,7alpha,24(S)-triol (the 24-hydroxy branch substrate).
Reason: Duplicate core molecular-function annotation from another Reactome reaction; correct and central to HSD3B7 function.
Supporting Evidence:
Reactome:R-HSA-193789
catalyzed by HSD3B7 (3 beta-hydroxysteroid dehydrogenase type 7) in the endoplasmic reticulum membrane
|
|
GO:0003854
3-beta-hydroxy-Delta5-steroid dehydrogenase (NAD+) activity
|
TAS
Reactome:R-HSA-193816 |
ACCEPT |
Summary: Same core 3-beta-hydroxy-Delta5-steroid dehydrogenase activity, annotated from the Reactome reaction on cholest-5-ene-3beta,7alpha,27-triol (the 27-hydroxy branch substrate).
Reason: Duplicate core molecular-function annotation from another Reactome reaction; correct and central to HSD3B7 function.
Supporting Evidence:
Reactome:R-HSA-193816
in a reaction catalyzed by HSD3B7 (3 beta-hydroxysteroid dehydrogenase type 7) in the endoplasmic reticulum membrane
|
|
GO:0005811
lipid droplet
|
IDA
GO_REF:0000052 |
KEEP AS NON CORE |
Summary: Immunofluorescence-based (HPA) localization to lipid droplets. HSD3B7's mechanistically-supported and primary compartment is the ER membrane; a lipid-droplet signal is plausible for an ER-associated lipid-metabolizing enzyme but is secondary.
Reason: The IDA/HPA lipid-droplet signal is a real immunolocalization observation but is not the primary functional compartment (ER membrane, multi-pass). Lipid droplets are ER-derived and this may reflect ER continuity; retain as non-core rather than treat as a core localization.
Supporting Evidence:
file:human/HSD3B7/HSD3B7-uniprot.txt
Endoplasmic reticulum membrane; Multi-pass
|
|
GO:0047016
cholest-5-ene-3-beta,7-alpha-diol 3-beta-dehydrogenase activity
|
EXP
PMID:11067870 The bile acid synthetic gene 3beta-hydroxy-Delta(5)-C(27)-st... |
ACCEPT |
Summary: Experimentally demonstrated activity - the expression-cloned C27 3beta-HSD acts on 7-alpha-hydroxylated sterols (cholest-5-ene-3-beta,7-alpha-diol, i.e. 7-alpha-hydroxycholesterol), catalyzing the 3-beta-dehydrogenation (EC 1.1.1.181). This is the specific, disease-relevant core molecular function.
Reason: Direct experimental evidence (transfection/activity assay) for this exact specific activity in the defining paper. Core molecular function.
Supporting Evidence:
PMID:11067870
active against four 7alpha-hydroxylated sterols
|
|
GO:0035754
B cell chemotaxis
|
ISS
GO_REF:0000024 |
KEEP AS NON CORE |
Summary: Sequence-similarity transfer from the mouse ortholog (Q9EQC1) of the role in lymphocyte positioning via degradation of the EBI2/GPR183 ligand 7-alpha,25-dihydroxycholesterol.
Reason: Same physiological role as the Ensembl IEA annotation, here as manual ISS from mouse. Genuine but peripheral relative to HSD3B7's core bile-acid catalytic function, and inferred by similarity; keep as non-core.
Supporting Evidence:
file:human/HSD3B7/HSD3B7-uniprot.txt
Plays a key role in cell positioning and
|
|
GO:0047016
cholest-5-ene-3-beta,7-alpha-diol 3-beta-dehydrogenase activity
|
ISS
GO_REF:0000024 |
ACCEPT |
Summary: Sequence-similarity transfer (from mouse Q9EQC1) of the specific 3-beta-dehydrogenase activity on 7-alpha-hydroxycholesterol. Corroborates the experimentally-established human activity.
Reason: The specific MF is independently demonstrated experimentally for the human enzyme (PMID:11067870); the ISS transfer is consistent and correct. Accept as core molecular function.
Supporting Evidence:
PMID:11067870
active against four 7alpha-hydroxylated sterols
|
|
GO:0005789
endoplasmic reticulum membrane
|
TAS
Reactome:R-HSA-192097 |
ACCEPT |
Summary: ER-membrane localization asserted by Reactome for the HSD3B7-catalyzed reaction. Consistent with UniProt (multi-pass ER membrane) and the microsomal enzyme described in PMID:11067870. Core localization.
Reason: Correct and core; matches the authoritative UniProt subcellular location and the biochemistry (microsomal fraction).
Supporting Evidence:
Reactome:R-HSA-192097
catalyzed by HSD3B7 (3 beta-hydroxysteroid dehydrogenase type 7) in the endoplasmic reticulum membrane
|
|
GO:0005789
endoplasmic reticulum membrane
|
TAS
Reactome:R-HSA-193789 |
ACCEPT |
Summary: Duplicate ER-membrane localization from another Reactome reaction for HSD3B7. Core localization.
Reason: Correct and core; consistent with UniProt subcellular location.
Supporting Evidence:
Reactome:R-HSA-193789
catalyzed by HSD3B7 (3 beta-hydroxysteroid dehydrogenase type 7) in the endoplasmic reticulum membrane
|
|
GO:0005789
endoplasmic reticulum membrane
|
TAS
Reactome:R-HSA-193816 |
ACCEPT |
Summary: Duplicate ER-membrane localization from another Reactome reaction for HSD3B7. Core localization.
Reason: Correct and core; consistent with UniProt subcellular location.
Supporting Evidence:
Reactome:R-HSA-193816
in a reaction catalyzed by HSD3B7 (3 beta-hydroxysteroid dehydrogenase type 7) in the endoplasmic reticulum membrane
|
|
GO:0003854
3-beta-hydroxy-Delta5-steroid dehydrogenase (NAD+) activity
|
NAS
PMID:11067870 The bile acid synthetic gene 3beta-hydroxy-Delta(5)-C(27)-st... |
ACCEPT |
Summary: Non-traceable-author-statement assignment of the general 3-beta-hydroxy-Delta5-steroid dehydrogenase (NAD+) activity, sourced to the defining paper. Consistent with the experimentally-established specific activity.
Reason: The core dehydrogenase molecular function is well supported by the same paper's experiments (PMID:11067870). Accept.
Supporting Evidence:
PMID:11067870
active against four 7alpha-hydroxylated sterols
|
|
GO:0006699
bile acid biosynthetic process
|
TAS
PMID:11067870 The bile acid synthetic gene 3beta-hydroxy-Delta(5)-C(27)-st... |
ACCEPT |
Summary: The defining paper establishes HSD3B7's central role in bile-acid biosynthesis; TAS annotation of the core biological process. Loss of activity causes a bile-acid synthesis defect (CBAS1).
Reason: Central, disease-defining biological process supported directly by PMID:11067870. Accept as core.
Supporting Evidence:
PMID:11067870
establish the central role of C(27) 3beta-HSD in the biosynthesis of bile acids
|
Human 3 beta-hydroxysteroid dehydrogenase type 7 / 3-beta-hydroxy-Delta(5)-C27-steroid
oxidoreductase (C27 3beta-HSD). EC 1.1.1.181. HGNC:18324. Chromosome 16p11.2-12.
protein binding (GO:0005515) IPIs from the two high-throughput interactome mapsid: Q9H2F3
gene_symbol: HSD3B7
product_type: PROTEIN
status: INITIALIZED
taxon:
id: NCBITaxon:9606
label: Homo sapiens
description: HSD3B7 (3 beta-hydroxysteroid dehydrogenase type 7; 3-beta-hydroxy-Delta(5)-C27-steroid
oxidoreductase, EC 1.1.1.181) catalyzes the second committed step of bile-acid biosynthesis.
Acting on the 7-alpha-hydroxylated sterols generated by CYP7A1/CYP7B1, it oxidizes the
3-beta-hydroxyl group and isomerizes the Delta5 double bond, converting 7-alpha-hydroxycholesterol
(and related 7-alpha-hydroxy-oxysterols such as 7-alpha,25-, 7-alpha,26- and 7-alpha,24-triols)
to the corresponding 3-oxo-Delta4 intermediates, e.g. 7-alpha-hydroxy-4-cholesten-3-one.
A single such enzyme feeds all known pathways of bile-acid synthesis. It is specific for
C27 bile-acid-precursor sterols and does not metabolize the C19/C21 steroids handled by
the steroidogenic paralogs HSD3B1/HSD3B2 (with which it shares only ~34% identity). HSD3B7
is a multi-pass endoplasmic-reticulum-membrane (microsomal) enzyme expressed predominantly
in liver. Loss-of-function mutations cause congenital bile acid synthesis defect type 1
(CBAS1), presenting as neonatal cholestasis, progressive liver disease and fat-soluble-vitamin
malabsorption. By acting on the oxysterol 7-alpha,25-dihydroxycholesterol, the enzyme also
contributes to turnover of the EBI2/GPR183 ligand that positions lymphocytes in lymphoid
tissue.
alternative_products:
- name: '1'
id: Q9H2F3-1
- name: '2'
id: Q9H2F3-2
sequence_note: VSP_042658
existing_annotations:
- term:
id: GO:0016616
label: oxidoreductase activity, acting on the CH-OH group of donors, NAD or NADP
as acceptor
evidence_type: IBA
original_reference_id: GO_REF:0000033
qualifier: enables
review:
summary: Broad phylogenetically-inferred molecular-function term correctly placing
HSD3B7 as an NAD(P)-dependent dehydrogenase acting on a CH-OH group. This is
accurate but general; the specific activity is the 3-beta-hydroxy-Delta5-steroid
dehydrogenase reaction on 7-alpha-hydroxylated C27 sterols.
action: MODIFY
reason: The IBA term is correct at the family level but too general for a gene
with a demonstrated specific catalytic activity. Retain the parent but propose
the specific dehydrogenase terms already supported by experiment (GO:0003854,
GO:0047016) as the core molecular function.
proposed_replacement_terms:
- id: GO:0003854
label: 3-beta-hydroxy-Delta5-steroid dehydrogenase (NAD+) activity
- id: GO:0047016
label: cholest-5-ene-3-beta,7-alpha-diol 3-beta-dehydrogenase activity
propagation_review:
root_cause: TERM_SCOPING_PROBLEM
failure_modes:
- GRANULARITY_MISMATCH
source_entities:
- source_id: PANTHER:PTN000041225
source_label: 3-beta-HSD family node (GO_Central IBA)
source_status: SUPPORTS_TRANSFER
comment: Family-level IBA correctly assigns the general NAD(P)-dependent CH-OH
dehydrogenase activity, but HSD3B7 has a demonstrated more specific
3-beta-hydroxy-Delta5-C27-steroid dehydrogenase activity (PMID:11067870).
supported_by:
- reference_id: file:human/HSD3B7/HSD3B7-uniprot.txt
supporting_text: HSD VII is active
- term:
id: GO:0005789
label: endoplasmic reticulum membrane
evidence_type: IEA
original_reference_id: GO_REF:0000044
qualifier: located_in
review:
summary: HSD3B7 is a multi-pass endoplasmic reticulum membrane (microsomal) protein;
this UniProt SubCellular-mapping IEA correctly captures the primary localization.
action: ACCEPT
reason: The ER membrane localization is directly stated in UniProt (SUBCELLULAR
LOCATION) and consistent with the microsomal enzyme described in PMID:11067870
and with the two predicted transmembrane helices. This is a core aspect of the
annotation.
supported_by:
- reference_id: file:human/HSD3B7/HSD3B7-uniprot.txt
supporting_text: 'Endoplasmic reticulum membrane; Multi-pass'
- term:
id: GO:0006694
label: steroid biosynthetic process
evidence_type: IEA
original_reference_id: GO_REF:0000120
qualifier: involved_in
review:
summary: Broad biosynthetic-process term. HSD3B7 participates in steroid (sterol/bile-acid)
biosynthesis, so the term is not wrong, but the specific and better-supported
process is bile acid biosynthesis (GO:0006699).
action: MODIFY
reason: Bile-acid precursors are C27 sterols and the enzyme is specific for the
bile-acid pathway; the more informative process term GO:0006699 is preferred.
The broad steroid-biosynthesis term is retained conceptually but should be specialized.
proposed_replacement_terms:
- id: GO:0006699
label: bile acid biosynthetic process
supported_by:
- reference_id: file:human/HSD3B7/HSD3B7-uniprot.txt
supporting_text: 'Lipid metabolism; steroid biosynthesis'
- term:
id: GO:0016616
label: oxidoreductase activity, acting on the CH-OH group of donors, NAD or NADP
as acceptor
evidence_type: IEA
original_reference_id: GO_REF:0000120
qualifier: enables
review:
summary: Same broad dehydrogenase molecular-function term as the IBA annotation,
here from InterPro/ARBA. Correct but general.
action: MODIFY
reason: Correct family-level assignment (NAD(P)-dependent CH-OH oxidoreductase),
but a more specific term is warranted given the demonstrated 3-beta-hydroxy-Delta5-steroid
dehydrogenase activity. Propose the specific MF terms.
proposed_replacement_terms:
- id: GO:0003854
label: 3-beta-hydroxy-Delta5-steroid dehydrogenase (NAD+) activity
- id: GO:0047016
label: cholest-5-ene-3-beta,7-alpha-diol 3-beta-dehydrogenase activity
supported_by:
- reference_id: file:human/HSD3B7/HSD3B7-uniprot.txt
supporting_text: HSD VII is active
- term:
id: GO:0047016
label: cholest-5-ene-3-beta,7-alpha-diol 3-beta-dehydrogenase activity
evidence_type: IEA
original_reference_id: GO_REF:0000120
qualifier: enables
review:
summary: Specific molecular-function term (EC 1.1.1.181) for the 3-beta-dehydrogenation
of the 7-alpha-hydroxylated sterol cholest-5-ene-3-beta,7-alpha-diol (7-alpha-hydroxycholesterol).
This is the demonstrated activity of HSD3B7 and is the core function; here inferred
electronically but corroborated by experiment (PMID:11067870).
action: ACCEPT
reason: This is exactly the biochemically characterized activity of HSD3B7 acting
on 7-alpha-hydroxycholesterol, matching the UniProt catalytic-activity entry (Rhea:11896,
EC 1.1.1.181). Accept as a core molecular function.
supported_by:
- reference_id: PMID:11067870
supporting_text: active against four 7alpha-hydroxylated sterols
- term:
id: GO:0005515
label: protein binding
evidence_type: IPI
original_reference_id: PMID:25416956
qualifier: enables
review:
summary: Generic protein-binding annotation from a proteome-scale (HuRI/CCSB) binary
interactome screen. The partner (SPRY2, O43597) is not part of a functionally
characterized HSD3B7 complex, and the bare protein-binding term is uninformative
about the enzyme's molecular function.
action: MARK_AS_OVER_ANNOTATED
reason: High-throughput interactome hits assigned only the uninformative GO:0005515
term. Per curation guidance, bare protein binding does not describe HSD3B7's
catalytic function; this is retained as an over-annotation rather than removed,
since the interaction data itself is experimental.
supported_by:
- reference_id: PMID:25416956
supporting_text: A proteome-scale map of the human interactome network
- term:
id: GO:0005515
label: protein binding
evidence_type: IPI
original_reference_id: PMID:32296183
qualifier: enables
review:
summary: Generic protein-binding annotations from the HuRI binary interactome map,
covering many heterogeneous partners (keratin-associated proteins, transcription
factors, etc.). None represent a defined functional HSD3B7 complex, and the term
is uninformative about molecular function.
action: MARK_AS_OVER_ANNOTATED
reason: These are large-scale yeast-two-hybrid/binary-screen hits annotated only
to the bare GO:0005515 term. Not informative for HSD3B7's dehydrogenase function;
marked as over-annotated per policy rather than removed.
supported_by:
- reference_id: PMID:32296183
supporting_text: A reference map of the human binary protein interactome
- term:
id: GO:0035754
label: B cell chemotaxis
evidence_type: IEA
original_reference_id: GO_REF:0000107
qualifier: involved_in
review:
summary: Biological-process annotation transferred by Ensembl Compara from the
mouse ortholog (Q9EQC1), reflecting HSD3B7's role in degrading the oxysterol
7-alpha,25-dihydroxycholesterol, an EBI2/GPR183 ligand that positions B cells
in lymphoid tissue.
action: KEEP_AS_NON_CORE
reason: This is a genuine but downstream/physiological consequence inferred from
the mouse ortholog, not HSD3B7's core catalytic role in bile-acid synthesis.
The human enzyme does act on 7-alpha,25-OHC in vitro (UniProt catalytic activity
Rhea:47156), supporting relevance, but the process is peripheral and evidence
is by-similarity; keep as non-core.
supported_by:
- reference_id: file:human/HSD3B7/HSD3B7-uniprot.txt
supporting_text: Plays a key role in cell positioning and
- term:
id: GO:0006699
label: bile acid biosynthetic process
evidence_type: TAS
original_reference_id: Reactome:R-HSA-193368
qualifier: involved_in
review:
summary: HSD3B7 catalyzes the second step of the classic (neutral) bile-acid pathway
via 7-alpha-hydroxycholesterol; Reactome annotates its participation in bile
acid biosynthesis. This is a core biological process for HSD3B7.
action: ACCEPT
reason: Bile acid biosynthesis is the central, disease-defining role of HSD3B7,
established biochemically and genetically (PMID:11067870). Accept as core.
supported_by:
- reference_id: PMID:11067870
supporting_text: a single C(27) 3beta-HSD enzyme can
participate in all known pathways of bile acid synthesis
- term:
id: GO:0006699
label: bile acid biosynthetic process
evidence_type: TAS
original_reference_id: Reactome:R-HSA-193775
qualifier: involved_in
review:
summary: Participation in bile-acid/bile-salt synthesis via the 24-hydroxycholesterol
(acidic/alternative) branch; HSD3B7 performs the 3-beta-dehydrogenation/isomerization
step on the 7-alpha-hydroxylated 24-hydroxy sterol. Core bile-acid process annotation.
action: ACCEPT
reason: Duplicate of the core bile-acid biosynthetic process annotation, from a
different Reactome pathway branch. Correct and core; the enzyme acts across all
bile-acid pathway branches.
supported_by:
- reference_id: PMID:11067870
supporting_text: a single C(27) 3beta-HSD enzyme can
participate in all known pathways of bile acid synthesis
- term:
id: GO:0006699
label: bile acid biosynthetic process
evidence_type: TAS
original_reference_id: Reactome:R-HSA-193807
qualifier: involved_in
review:
summary: Participation in bile-acid/bile-salt synthesis via the 27-hydroxycholesterol
branch. HSD3B7 acts on the 7-alpha-hydroxylated 27-hydroxy sterol. Core bile-acid
process annotation.
action: ACCEPT
reason: Duplicate of the core bile-acid biosynthetic process annotation from another
Reactome branch. Consistent with the enzyme's broad substrate range across
bile-acid pathways.
supported_by:
- reference_id: PMID:11067870
supporting_text: a single C(27) 3beta-HSD enzyme can
participate in all known pathways of bile acid synthesis
- term:
id: GO:0003854
label: 3-beta-hydroxy-Delta5-steroid dehydrogenase (NAD+) activity
evidence_type: TAS
original_reference_id: Reactome:R-HSA-192097
qualifier: enables
review:
summary: Core molecular function - NAD+-dependent 3-beta-hydroxy-Delta5-steroid
dehydrogenase (with associated isomerase activity). Reactome R-HSA-192097 describes
HSD3B7 oxidizing/isomerizing 7-alpha-hydroxycholesterol to 4-cholesten-7-alpha-ol-3-one.
action: ACCEPT
reason: This is the defining catalytic activity of HSD3B7, supported by biochemistry
(PMID:11067870) and by the Reactome reaction. Accept as a core molecular function.
supported_by:
- reference_id: Reactome:R-HSA-192097
supporting_text: catalyzed by HSD3B7 (3 beta-hydroxysteroid
dehydrogenase type 7) in the endoplasmic reticulum membrane
- term:
id: GO:0003854
label: 3-beta-hydroxy-Delta5-steroid dehydrogenase (NAD+) activity
evidence_type: TAS
original_reference_id: Reactome:R-HSA-193789
qualifier: enables
review:
summary: Same core 3-beta-hydroxy-Delta5-steroid dehydrogenase activity, annotated
from the Reactome reaction on cholest-5-ene-3beta,7alpha,24(S)-triol (the 24-hydroxy
branch substrate).
action: ACCEPT
reason: Duplicate core molecular-function annotation from another Reactome reaction;
correct and central to HSD3B7 function.
supported_by:
- reference_id: Reactome:R-HSA-193789
supporting_text: catalyzed by HSD3B7 (3 beta-hydroxysteroid dehydrogenase type 7)
in the endoplasmic reticulum membrane
- term:
id: GO:0003854
label: 3-beta-hydroxy-Delta5-steroid dehydrogenase (NAD+) activity
evidence_type: TAS
original_reference_id: Reactome:R-HSA-193816
qualifier: enables
review:
summary: Same core 3-beta-hydroxy-Delta5-steroid dehydrogenase activity, annotated
from the Reactome reaction on cholest-5-ene-3beta,7alpha,27-triol (the 27-hydroxy
branch substrate).
action: ACCEPT
reason: Duplicate core molecular-function annotation from another Reactome reaction;
correct and central to HSD3B7 function.
supported_by:
- reference_id: Reactome:R-HSA-193816
supporting_text: in a reaction catalyzed by HSD3B7 (3 beta-hydroxysteroid
dehydrogenase type 7) in the endoplasmic reticulum membrane
- term:
id: GO:0005811
label: lipid droplet
evidence_type: IDA
original_reference_id: GO_REF:0000052
qualifier: located_in
review:
summary: Immunofluorescence-based (HPA) localization to lipid droplets. HSD3B7's
mechanistically-supported and primary compartment is the ER membrane; a lipid-droplet
signal is plausible for an ER-associated lipid-metabolizing enzyme but is secondary.
action: KEEP_AS_NON_CORE
reason: The IDA/HPA lipid-droplet signal is a real immunolocalization observation
but is not the primary functional compartment (ER membrane, multi-pass). Lipid
droplets are ER-derived and this may reflect ER continuity; retain as non-core
rather than treat as a core localization.
supported_by:
- reference_id: file:human/HSD3B7/HSD3B7-uniprot.txt
supporting_text: 'Endoplasmic reticulum membrane; Multi-pass'
- term:
id: GO:0047016
label: cholest-5-ene-3-beta,7-alpha-diol 3-beta-dehydrogenase activity
evidence_type: EXP
original_reference_id: PMID:11067870
qualifier: enables
review:
summary: Experimentally demonstrated activity - the expression-cloned C27 3beta-HSD
acts on 7-alpha-hydroxylated sterols (cholest-5-ene-3-beta,7-alpha-diol, i.e.
7-alpha-hydroxycholesterol), catalyzing the 3-beta-dehydrogenation (EC 1.1.1.181).
This is the specific, disease-relevant core molecular function.
action: ACCEPT
reason: Direct experimental evidence (transfection/activity assay) for this exact
specific activity in the defining paper. Core molecular function.
supported_by:
- reference_id: PMID:11067870
supporting_text: active against four 7alpha-hydroxylated sterols
- term:
id: GO:0035754
label: B cell chemotaxis
evidence_type: ISS
original_reference_id: GO_REF:0000024
qualifier: involved_in
review:
summary: Sequence-similarity transfer from the mouse ortholog (Q9EQC1) of the role
in lymphocyte positioning via degradation of the EBI2/GPR183 ligand 7-alpha,25-dihydroxycholesterol.
action: KEEP_AS_NON_CORE
reason: Same physiological role as the Ensembl IEA annotation, here as manual ISS
from mouse. Genuine but peripheral relative to HSD3B7's core bile-acid catalytic
function, and inferred by similarity; keep as non-core.
supported_by:
- reference_id: file:human/HSD3B7/HSD3B7-uniprot.txt
supporting_text: Plays a key role in cell positioning and
- term:
id: GO:0047016
label: cholest-5-ene-3-beta,7-alpha-diol 3-beta-dehydrogenase activity
evidence_type: ISS
original_reference_id: GO_REF:0000024
qualifier: enables
review:
summary: Sequence-similarity transfer (from mouse Q9EQC1) of the specific 3-beta-dehydrogenase
activity on 7-alpha-hydroxycholesterol. Corroborates the experimentally-established
human activity.
action: ACCEPT
reason: The specific MF is independently demonstrated experimentally for the human
enzyme (PMID:11067870); the ISS transfer is consistent and correct. Accept as
core molecular function.
supported_by:
- reference_id: PMID:11067870
supporting_text: active against four 7alpha-hydroxylated sterols
- term:
id: GO:0005789
label: endoplasmic reticulum membrane
evidence_type: TAS
original_reference_id: Reactome:R-HSA-192097
qualifier: located_in
review:
summary: ER-membrane localization asserted by Reactome for the HSD3B7-catalyzed
reaction. Consistent with UniProt (multi-pass ER membrane) and the microsomal
enzyme described in PMID:11067870. Core localization.
action: ACCEPT
reason: Correct and core; matches the authoritative UniProt subcellular location
and the biochemistry (microsomal fraction).
supported_by:
- reference_id: Reactome:R-HSA-192097
supporting_text: catalyzed by HSD3B7 (3 beta-hydroxysteroid
dehydrogenase type 7) in the endoplasmic reticulum membrane
- term:
id: GO:0005789
label: endoplasmic reticulum membrane
evidence_type: TAS
original_reference_id: Reactome:R-HSA-193789
qualifier: located_in
review:
summary: Duplicate ER-membrane localization from another Reactome reaction for
HSD3B7. Core localization.
action: ACCEPT
reason: Correct and core; consistent with UniProt subcellular location.
supported_by:
- reference_id: Reactome:R-HSA-193789
supporting_text: catalyzed by HSD3B7 (3 beta-hydroxysteroid dehydrogenase type 7)
in the endoplasmic reticulum membrane
- term:
id: GO:0005789
label: endoplasmic reticulum membrane
evidence_type: TAS
original_reference_id: Reactome:R-HSA-193816
qualifier: located_in
review:
summary: Duplicate ER-membrane localization from another Reactome reaction for
HSD3B7. Core localization.
action: ACCEPT
reason: Correct and core; consistent with UniProt subcellular location.
supported_by:
- reference_id: Reactome:R-HSA-193816
supporting_text: in a reaction catalyzed by HSD3B7 (3 beta-hydroxysteroid dehydrogenase type 7)
in the endoplasmic reticulum membrane
- term:
id: GO:0003854
label: 3-beta-hydroxy-Delta5-steroid dehydrogenase (NAD+) activity
evidence_type: NAS
original_reference_id: PMID:11067870
qualifier: enables
review:
summary: Non-traceable-author-statement assignment of the general 3-beta-hydroxy-Delta5-steroid
dehydrogenase (NAD+) activity, sourced to the defining paper. Consistent with
the experimentally-established specific activity.
action: ACCEPT
reason: The core dehydrogenase molecular function is well supported by the same
paper's experiments (PMID:11067870). Accept.
supported_by:
- reference_id: PMID:11067870
supporting_text: active against four 7alpha-hydroxylated sterols
- term:
id: GO:0006699
label: bile acid biosynthetic process
evidence_type: TAS
original_reference_id: PMID:11067870
qualifier: involved_in
review:
summary: The defining paper establishes HSD3B7's central role in bile-acid biosynthesis;
TAS annotation of the core biological process. Loss of activity causes a bile-acid
synthesis defect (CBAS1).
action: ACCEPT
reason: Central, disease-defining biological process supported directly by PMID:11067870.
Accept as core.
supported_by:
- reference_id: PMID:11067870
supporting_text: establish the central role of C(27) 3beta-HSD in the
biosynthesis of bile acids
core_functions:
- description: NAD+-dependent 3-beta-hydroxy-Delta5-steroid dehydrogenase/isomerase that
oxidizes the 3-beta-hydroxyl and isomerizes the Delta5 double bond of 7-alpha-hydroxylated
C27 sterols (e.g. 7-alpha-hydroxycholesterol -> 7-alpha-hydroxy-4-cholesten-3-one),
the second step of bile-acid biosynthesis.
molecular_function:
id: GO:0003854
label: 3-beta-hydroxy-Delta5-steroid dehydrogenase (NAD+) activity
directly_involved_in:
- id: GO:0006699
label: bile acid biosynthetic process
locations:
- id: GO:0005789
label: endoplasmic reticulum membrane
supported_by:
- reference_id: PMID:11067870
supporting_text: active against four 7alpha-hydroxylated sterols
- description: Specific 3-beta-dehydrogenation of the 7-alpha-hydroxylated sterol
cholest-5-ene-3-beta,7-alpha-diol (7-alpha-hydroxycholesterol), EC 1.1.1.181,
the biochemically demonstrated bile-acid-precursor-specific activity of HSD3B7.
molecular_function:
id: GO:0047016
label: cholest-5-ene-3-beta,7-alpha-diol 3-beta-dehydrogenase activity
directly_involved_in:
- id: GO:0006699
label: bile acid biosynthetic process
locations:
- id: GO:0005789
label: endoplasmic reticulum membrane
supported_by:
- reference_id: PMID:11067870
supporting_text: active against four 7alpha-hydroxylated sterols
references:
- id: GO_REF:0000024
title: Manual transfer of experimentally-verified manual GO annotation data to orthologs
by curator judgment of sequence similarity
findings: []
- id: GO_REF:0000033
title: Annotation inferences using phylogenetic trees
findings: []
- id: GO_REF:0000044
title: Gene Ontology annotation based on UniProtKB/Swiss-Prot Subcellular Location
vocabulary mapping, accompanied by conservative changes to GO terms applied by
UniProt
findings: []
- id: GO_REF:0000052
title: Gene Ontology annotation based on curation of immunofluorescence data
findings: []
- id: GO_REF:0000107
title: Automatic transfer of experimentally verified manual GO annotation data to
orthologs using Ensembl Compara
findings: []
- id: GO_REF:0000120
title: Combined Automated Annotation using Multiple IEA Methods
findings: []
- id: file:human/HSD3B7/HSD3B7-uniprot.txt
title: UniProtKB Q9H2F3 (3BHS7_HUMAN) - 3 beta-hydroxysteroid dehydrogenase type 7
findings: []
- id: PMID:11067870
title: The bile acid synthetic gene 3beta-hydroxy-Delta(5)-C(27)-steroid oxidoreductase
is mutated in progressive intrahepatic cholestasis.
findings: []
reference_review:
relevance: HIGH
correctness: VERIFIED
review_notes: PubMed-verified defining paper; expression cloning shows the C27
3beta-HSD acts on four 7-alpha-hydroxylated sterols, does not metabolize C19/21
steroids, and that loss of activity causes neonatal cholestasis. Abstract-only
in cache (full_text_available false); quotes taken verbatim from the abstract.
- id: PMID:25416956
title: A proteome-scale map of the human interactome network.
findings: []
reference_review:
relevance: LOW
correctness: VERIFIED
review_notes: High-throughput interactome map (HuRI/CCSB); source of bare protein-binding
IPI. Correctly cited but uninformative for HSD3B7's molecular function.
- id: PMID:32296183
title: A reference map of the human binary protein interactome.
findings: []
reference_review:
relevance: LOW
correctness: VERIFIED
review_notes: HuRI binary interactome map; source of numerous bare protein-binding
IPIs. Correctly cited but uninformative for HSD3B7's molecular function.
- id: Reactome:R-HSA-192097
title: 7alpha-hydroxycholesterol is oxidized and isomerized to 4-cholesten-7alpha-ol-3-one
findings: []
- id: Reactome:R-HSA-193368
title: Synthesis of bile acids and bile salts via 7alpha-hydroxycholesterol
findings: []
- id: Reactome:R-HSA-193775
title: Synthesis of bile acids and bile salts via 24-hydroxycholesterol
findings: []
- id: Reactome:R-HSA-193789
title: Cholest-5-ene-3beta,7alpha,24(S)-triol is oxidized and isomerized to 4-cholesten-7alpha,24(S)-diol-3-one
findings: []
- id: Reactome:R-HSA-193807
title: Synthesis of bile acids and bile salts via 27-hydroxycholesterol
findings: []
- id: Reactome:R-HSA-193816
title: Cholest-5-ene-3beta,7alpha,27-triol is oxidized and isomerized to 4-cholesten-7alpha,27-diol-3-one
findings: []