Existing Annotations Review

GO Term	Evidence	Action	Reason
GO:0005737 cytoplasm	IEA GO_REF:0000117	KEEP AS NON CORE	Summary: Electronic cytoplasm annotation. CSP-beta is a membrane-anchored co-chaperone with a cytoplasmic-facing pool. Reason: Generic cytoplasm localization; consistent with a J-domain co-chaperone but less informative than its membrane/TGN association. Supporting Evidence: file:human/DNAJC5B/DNAJC5B-uniprot.txt Interacts with the chaperone complex consisting of HSC70
GO:0016020 membrane	IEA GO_REF:0000044	ACCEPT	Summary: Membrane localization from UniProt subcellular-location mapping, experimentally supported by detection as a lipid-anchored, TGN-associated protein. Reason: CSP-beta is experimentally documented as a membrane (lipid-anchor) protein that may associate with the trans-Golgi network; membrane is its core compartment. Supporting Evidence: file:human/DNAJC5B/DNAJC5B-uniprot.txt SUBCELLULAR LOCATION: Membrane
GO:0005515 protein binding	IPI PMID:25416956 A proteome-scale map of the human interactome network.	KEEP AS NON CORE	Summary: Proteome-scale yeast two-hybrid map capturing a CSP-beta-TFCP2 interaction. The bare protein binding term is uninformative and the partner (the transcription factor TFCP2/CP2) does not define a chaperone function. Reason: Records a single high-throughput interaction; bare protein binding is uninformative and is not elevated to core. Supporting Evidence: file:human/DNAJC5B/DNAJC5B-uniprot.txt Q9UF47; Q12800: TFCP2; NbExp=3

Core Functions

HSP70/HSC70 co-chaperone defined by an N-terminal J domain, experimentally shown to interact with the HSC70-SGTA chaperone complex; acts in a testis-specific, membrane/trans-Golgi-network context.

Molecular Function:

Hsp70 protein binding

Cellular Locations:

membrane

Supporting Evidence:

file:human/DNAJC5B/DNAJC5B-uniprot.txt
Interacts with the chaperone complex consisting of HSC70

References

GO_REF:0000044

Gene Ontology annotation through association of InterPro records with GO terms

GO_REF:0000117

Electronic Gene Ontology annotations created by ARBA machine learning models

PMID:25416956

A proteome-scale map of the human interactome network.

PMID:17034881

Cysteine-string protein isoform beta (Cspbeta) is targeted to the trans-Golgi network as a non-palmitoylated CSP in clonal beta-cells.

CSP-beta interacts with the HSC70 and SGTA chaperone complex and is a membrane-anchored protein targeted to the trans-Golgi network; its membrane association does not require palmitoylation.

file:human/DNAJC5B/DNAJC5B-uniprot.txt

UniProt entry Q9UF47 (DNJ5B_HUMAN), cysteine-string protein isoform beta

Testis-specific CSP paralog; J domain (aa 19-84); interacts with the HSC70/SGTA chaperone complex; membrane lipid-anchor associated with the trans-Golgi network; palmitoylated but palmitoylation is not required for membrane association.

Suggested Experiments

Experiment: Reconstituted HSC70 ATPase assays with purified CSP-beta (wild-type and J-domain HPD mutant) to confirm co-chaperone activity.

Experiment: Affinity purification-mass spectrometry of tagged CSP-beta from a testis-derived or beta-cell line to identify its client/interaction network and any secretory-pathway partners.

📚 Additional Documentation

Notes

(DNAJC5B-notes.md)

DNAJC5B (Q9UF47) research notes

Identity

DnaJ homolog subfamily C member 5B; cysteine-string protein isoform beta (CSP-beta). Paralog of DNAJC5/CSPalpha.
199 aa. J domain (aa 19-84) [file:human/DNAJC5B/DNAJC5B-uniprot.txt "DOMAIN 19..84 /note=\"J\""]. Cysteine-string region downstream of J domain. Palmitoylated.
Testis specific [uniprot "TISSUE SPECIFICITY: Testis specific"].

Function / experimental data

PMID:17034881 (Boal et al. 2007, BBA): CSP-beta interacts with the HSC70+SGTA chaperone complex; targeted to the trans-Golgi network as a non-palmitoylated CSP in clonal beta-cells; palmitoylation NOT required for membrane association.
UniProt SUBUNIT: "Interacts with the chaperone complex consisting of HSC70 and SGTA." -> bona fide HSP70/HSC70 co-chaperone (like CSPalpha), but tissue-restricted (testis) and TGN-targeted.
SUBCELLULAR LOCATION: Membrane; Lipid-anchor; may be associated with trans-Golgi network.

Interactions (GOA)

protein binding IPI with TFCP2 (Q12800) from PMID:25416956 (proteome-scale Y2H map). Uninformative HT interaction; partner is a transcription factor (CP2), not a chaperone client.

Curation judgment

Core MF: HSP70/HSC70 co-chaperone (Hsp70 protein binding) — supported by experimental HSC70/SGTA interaction.
Membrane / cytoplasm localizations: ACCEPT/KEEP_AS_NON_CORE (membrane is lipid-anchored; TGN association).
protein binding IPI (TFCP2): KEEP_AS_NON_CORE (uninformative HT).

Pn Notes

(DNAJC5B-pn-notes.md)

DNAJC5B PN Consistency Notes

Generated: 2026-06-18
Project: PROTEOSTASIS
Scope: PN consistency rereview against local AIGR review and available deep-research artifacts
UniProt: Q9UF47
AIGR review status: COMPLETE
Review batch: proteostasis-batch-2026-06-07b
Batch change status: added

Source Files Checked

AIGR review YAML: present - genes/human/DNAJC5B/DNAJC5B-ai-review.yaml
AIGR review HTML: present - genes/human/DNAJC5B/DNAJC5B-ai-review.html
Gene notes: present - genes/human/DNAJC5B/DNAJC5B-notes.md
GOA TSV: present - genes/human/DNAJC5B/DNAJC5B-goa.tsv
UniProt record: present - genes/human/DNAJC5B/DNAJC5B-uniprot.txt
PN dossier: projects/PROTEOSTASIS/reports/phase1_dossiers/DNAJC5B.md
PN consistency section: projects/PROTEOSTASIS/reports/phase1_dossiers/_sections/DNAJC5B.md
PN projection report: projects/PROTEOSTASIS/reports/pn_projection/pn_projected_gene_go_summary.tsv
PN mapping audit: projects/PROTEOSTASIS/reports/pn_mapping_audit/current_mapping_scrutiny.tsv

Deep Research Files

No *-deep-research*.md file found in this gene directory.

AIGR Review Snapshot

Description: DNAJC5B (cysteine-string protein isoform beta, CSP-beta) is a testis-specific paralog of the synaptic co-chaperone CSPalpha/DNAJC5. Like other cysteine string proteins it has an N-terminal J domain that engages the constitutive HSP70 chaperone HSC70/HSPA8 and a downstream cysteine-string region that can be palmitoylated. CSP-beta interacts with the HSC70-SGTA chaperone complex and is membrane-anchored, associating with the trans-Golgi network; unlike CSPalpha its membrane association does not require palmitoylation. Its physiological role is presumed to be HSP70 co-chaperone activity in a secretory/membrane-trafficking context of the testis, but it is otherwise poorly characterized.
Existing/core annotation action counts: ACCEPT: 1; KEEP_AS_NON_CORE: 2

PN Consistency Summary

Consistency: Consistent. Deep research (notes), review and PN converge on DNAJC5B/CSP-beta as a testis-specific CSPalpha paralog (J domain aa 19-84) that interacts with the HSC70-SGTA chaperone complex and targets the trans-Golgi network as a non-palmitoylated CSP (PMID:17034881, Boal et al.). The review's core MF is exactly GO:0030544 Hsp70 protein binding, matching the PN projection. The TGN/secretory-pathway context makes the ER-branch placement reasonable. The HSC70/SGTA interaction is experimentally documented (not just family inference), so GO:0030544 here is better-supported than for the Tdark paralogs DNAJC4/DNAJC5G.
PN story / NEW pressure: GO:0030544 is already the review's core MF → already captured (verified real). goa_status=more_specific_than_existing_goa is accurate (GOA had no chaperone-binding MF, only membrane/cytoplasm + one HT protein-binding IPI with TFCP2). The Hsp70-cochaperone assertion is genuine MF (the experimental HSC70-SGTA interaction), not an over-broad holdase claim.
Evidence alignment: PN carries no row references. Review cites PMID:17034881 (HIGH relevance, UNVERIFIED/uncached primary functional paper) and PMID:25416956 (proteome-scale Y2H, TFCP2 HT hit). No divergence from PN.
Verdict: Fully consistent; PN Hsp70-binding story already captured as core MF and experimentally supported via HSC70/SGTA. Recommended edits: none required.

Full Consistency Review

UniProt: Q9UF47 · batch: proteostasis-batch-2026-06-07b · review status: COMPLETE
PN placement: ER proteostasis|Chaperone|HSP70 system|J-domain containing HSP70 cochaperone (branch ER) ; PN-node mapping: type → mapped/ok_for_propagation_to_go GO:0030544 Hsp70 protein binding (goa_status=more_specific_than_existing_goa); all ancestor nodes no_mapping.
Consistency: Consistent. Deep research (notes), review and PN converge on DNAJC5B/CSP-beta as a testis-specific CSPalpha paralog (J domain aa 19-84) that interacts with the HSC70-SGTA chaperone complex and targets the trans-Golgi network as a non-palmitoylated CSP (PMID:17034881, Boal et al.). The review's core MF is exactly GO:0030544 Hsp70 protein binding, matching the PN projection. The TGN/secretory-pathway context makes the ER-branch placement reasonable. The HSC70/SGTA interaction is experimentally documented (not just family inference), so GO:0030544 here is better-supported than for the Tdark paralogs DNAJC4/DNAJC5G.
PN story / NEW pressure: GO:0030544 is already the review's core MF → already captured (verified real). goa_status=more_specific_than_existing_goa is accurate (GOA had no chaperone-binding MF, only membrane/cytoplasm + one HT protein-binding IPI with TFCP2). The Hsp70-cochaperone assertion is genuine MF (the experimental HSC70-SGTA interaction), not an over-broad holdase claim.
Mapping strategy: No change to the node. GO:0030544 is the correct breadth and is experimentally anchored for this gene.
Evidence alignment: PN carries no row references. Review cites PMID:17034881 (HIGH relevance, UNVERIFIED/uncached primary functional paper) and PMID:25416956 (proteome-scale Y2H, TFCP2 HT hit). No divergence from PN.
Verdict: Fully consistent; PN Hsp70-binding story already captured as core MF and experimentally supported via HSC70/SGTA. Recommended edits: none required.

PN Dossier Context

review_batch: proteostasis-batch-2026-06-07b
review_yaml: genes/human/DNAJC5B/DNAJC5B-ai-review.yaml
PN workbook rows: 1

PN row 1: ER proteostasis | Chaperone | HSP70 system | J-domain containing HSP70 cochaperone

UniProt: Q9UF47
In branches: ER
PN-node mapping records (path + ancestors):
- [type] ER proteostasis|Chaperone|HSP70 system|J-domain containing HSP70 cochaperone
  status=mapped scope=ok_for_propagation_to_go GO=[GO:0030544 Hsp70 protein binding]
  rationale: In the PN hierarchy, this type denotes J-domain cochaperones assigned to the HSP70 system. Their shared mechanistic role is direct interaction with HSP70-family chaperones, making Hsp70 protein binding the most defensible GO target in the current cache.
- [group] ER proteostasis|Chaperone|HSP70 system
  status=no_mapping scope= GO=[]
  rationale: Reviewed as a broad PN category rather than a single GO class. The member genes span multiple activities, complexes, or contexts, so direct propagation from this node would overstate the shared biology.
- [class] ER proteostasis|Chaperone
  status=no_mapping scope= GO=[]
  rationale: Reviewed as a broad PN category rather than a single GO class. The member genes span multiple activities, complexes, or contexts, so direct propagation from this node would overstate the shared biology.
- [branch] ER proteostasis
  status=no_mapping scope= GO=[]
  rationale: Reviewed as a top-level PN branch. This is a systems/taxonomy umbrella, not a direct GO assertion; narrower child curations carry any propagating GO mappings.

Projected GO annotations (1)

GO:0030544 Hsp70 protein binding | scope=ok_for_propagation_to_go | goa_status=more_specific_than_existing_goa | from=ER proteostasis|Chaperone|HSP70 system|J-domain containing HSP70 cochaperone

Note

This file is generated from the current PROTEOSTASIS phase-1 dossier and local gene-review artifacts. Edit the source review, PN mapping, or dossier rather than this generated note when correcting the underlying curation.

📄 View Raw YAML

id: Q9UF47
gene_symbol: DNAJC5B
product_type: PROTEIN
status: COMPLETE
taxon:
  id: NCBITaxon:9606
  label: Homo sapiens
description: DNAJC5B (cysteine-string protein isoform beta, CSP-beta) is a testis-specific
  paralog of the synaptic co-chaperone CSPalpha/DNAJC5. Like other cysteine string
  proteins it has an N-terminal J domain that engages the constitutive HSP70 chaperone
  HSC70/HSPA8 and a downstream cysteine-string region that can be palmitoylated. CSP-beta
  interacts with the HSC70-SGTA chaperone complex and is membrane-anchored, associating
  with the trans-Golgi network; unlike CSPalpha its membrane association does not require
  palmitoylation. Its physiological role is presumed to be HSP70 co-chaperone activity
  in a secretory/membrane-trafficking context of the testis, but it is otherwise poorly
  characterized.
existing_annotations:
- term:
    id: GO:0005737
    label: cytoplasm
  evidence_type: IEA
  original_reference_id: GO_REF:0000117
  qualifier: located_in
  review:
    summary: Electronic cytoplasm annotation. CSP-beta is a membrane-anchored co-chaperone
      with a cytoplasmic-facing pool.
    action: KEEP_AS_NON_CORE
    reason: Generic cytoplasm localization; consistent with a J-domain co-chaperone
      but less informative than its membrane/TGN association.
    supported_by:
    - reference_id: file:human/DNAJC5B/DNAJC5B-uniprot.txt
      supporting_text: Interacts with the chaperone complex consisting of HSC70
- term:
    id: GO:0016020
    label: membrane
  evidence_type: IEA
  original_reference_id: GO_REF:0000044
  qualifier: located_in
  review:
    summary: Membrane localization from UniProt subcellular-location mapping, experimentally
      supported by detection as a lipid-anchored, TGN-associated protein.
    action: ACCEPT
    reason: CSP-beta is experimentally documented as a membrane (lipid-anchor) protein
      that may associate with the trans-Golgi network; membrane is its core compartment.
    supported_by:
    - reference_id: file:human/DNAJC5B/DNAJC5B-uniprot.txt
      supporting_text: 'SUBCELLULAR LOCATION: Membrane'
- term:
    id: GO:0005515
    label: protein binding
  evidence_type: IPI
  original_reference_id: PMID:25416956
  qualifier: enables
  review:
    summary: Proteome-scale yeast two-hybrid map capturing a CSP-beta-TFCP2 interaction.
      The bare protein binding term is uninformative and the partner (the transcription
      factor TFCP2/CP2) does not define a chaperone function.
    action: KEEP_AS_NON_CORE
    reason: Records a single high-throughput interaction; bare protein binding is
      uninformative and is not elevated to core.
    supported_by:
    - reference_id: file:human/DNAJC5B/DNAJC5B-uniprot.txt
      supporting_text: 'Q9UF47; Q12800: TFCP2; NbExp=3'
references:
- id: GO_REF:0000044
  title: Gene Ontology annotation through association of InterPro records with GO
    terms
  findings: []
- id: GO_REF:0000117
  title: Electronic Gene Ontology annotations created by ARBA machine learning models
  findings: []
- id: PMID:25416956
  title: A proteome-scale map of the human interactome network.
  findings: []
- id: PMID:17034881
  title: Cysteine-string protein isoform beta (Cspbeta) is targeted to the trans-Golgi
    network as a non-palmitoylated CSP in clonal beta-cells.
  reference_review:
    relevance: HIGH
    correctness: UNVERIFIED
    review_notes: "Primary functional reference for CSP-beta/DNAJC5B: reports its
      membrane targeting to the trans-Golgi network and association with the HSC70/
      SGTA chaperone complex, the basis for the co-chaperone and membrane-localization
      annotations. Not cached in publications/, so the identifier/content could not be
      checked against a cached/PubMed anchor; title is consistent with the claim but
      left UNVERIFIED."
  findings:
  - statement: CSP-beta interacts with the HSC70 and SGTA chaperone complex and is
      a membrane-anchored protein targeted to the trans-Golgi network; its membrane
      association does not require palmitoylation.
    reference_section_type: RESULTS
- id: file:human/DNAJC5B/DNAJC5B-uniprot.txt
  title: UniProt entry Q9UF47 (DNJ5B_HUMAN), cysteine-string protein isoform beta
  findings:
  - statement: Testis-specific CSP paralog; J domain (aa 19-84); interacts with the
      HSC70/SGTA chaperone complex; membrane lipid-anchor associated with the trans-Golgi
      network; palmitoylated but palmitoylation is not required for membrane association.
    reference_section_type: OTHER
core_functions:
- description: HSP70/HSC70 co-chaperone defined by an N-terminal J domain, experimentally
    shown to interact with the HSC70-SGTA chaperone complex; acts in a testis-specific,
    membrane/trans-Golgi-network context.
  molecular_function:
    id: GO:0030544
    label: Hsp70 protein binding
  locations:
  - id: GO:0016020
    label: membrane
  supported_by:
  - reference_id: file:human/DNAJC5B/DNAJC5B-uniprot.txt
    supporting_text: Interacts with the chaperone complex consisting of HSC70
proposed_new_terms: []
suggested_questions:
- question: What is the testis-specific physiological function of CSP-beta, and does
    it chaperone a secretory or membrane-trafficking client analogous to CSPalpha's
    SNAP-25?
- question: Does CSP-beta stimulate HSC70 ATPase activity via its J domain, and how
    does its palmitoylation-independent membrane targeting differ mechanistically
    from CSPalpha?
suggested_experiments:
- description: Reconstituted HSC70 ATPase assays with purified CSP-beta (wild-type
    and J-domain HPD mutant) to confirm co-chaperone activity.
- description: Affinity purification-mass spectrometry of tagged CSP-beta from a testis-derived
    or beta-cell line to identify its client/interaction network and any secretory-pathway
    partners.

DNAJC5B

Gene Description