## DNAJB13
- **UniProt:** P59910 (TSARG3/TSARG6) · **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, scope=ok_for_propagation_to_go, GO:0030544 Hsp70 protein binding (parents no_mapping)
- **Consistency:** CONTRADICTION — this is the misfit. Notes and review YAML both conclude DNAJB13 is functionally a *structural* component of the axonemal radial spoke (RS1 stalk), NOT a working cytosolic HSP70 co-chaperone. The review actively downgrades the J-protein/HSP70 inferences: GO:0051087 chaperone binding and GO:0006457 folding are KEEP_AS_NON_CORE ("not experimentally demonstrated"), and IBA cytosol (GO:0005829) is MARK_AS_OVER_ANNOTATED. Core MF is assigned as GO:0030674 protein-macromolecule adaptor activity, located in radial spoke/axoneme. The PN placement under "HSP70 system | J-domain HSP70 cochaperone" with a mapped GO:0030544 directly conflicts with the review's verdict that no HSP70-binding function is demonstrated for this protein. Also note: PN puts it in the *ER* branch, but DNAJB13 is axonemal/ciliary — not an ER protein.
- **PN story / NEW pressure:** PN asserts HSP70 binding the review explicitly rejects as undemonstrated. No NEW GO pressure for proteostasis; the gene's defensible terms are cilium/flagellum/radial-spoke (GO:0001534, GO:0005930, GO:1904158, GO:0030317, GO:0003341) — all already captured. Over-reaches as a proteostasis HSP70 cochaperone.
- **Mapping strategy:** The type-level GO:0030544 mapping should NOT propagate to DNAJB13 — it is a catalytically/functionally divergent J-domain member whose J domain appears repurposed structurally (review's own suggested experiment asks whether HSP70-stimulating activity is retained at all). This is exactly the "distinguish genuine Hsp70-cochaperone from members lacking direct evidence" flag.
- **Evidence alignment:** PN cochaperone framing diverges from the review's evidence (PMID:27486783 PCD/radial spoke; PMID:36417862 RS1) which is entirely axonemal. No HSP70/BiP papers in the review.
- **Verdict:** OVER-REACH / MISPLACED — DNAJB13 should be excluded from the HSP70-cochaperone GO:0030544 propagation (and arguably from the ER/HSP70-system PN node); its function is structural radial-spoke, captured by GO:0001534/GO:0030674.
- **Recommended edits:** [MAP] Exclude DNAJB13 from the `J-domain containing HSP70 cochaperone` GO:0030544 projection (catalytically-divergent, no HSP70-binding evidence; function is structural radial-spoke). [MAP] Re-examine its ER-branch placement (protein is axonemal, not ER-resident).