## SEC63
- **UniProt:** Q9UGP8 (DNAJC23) · **batch:** proteostasis-batch-2026-06-11 · **review status:** COMPLETE
- **PN placement:** `ER proteostasis|Chaperone|HSP70 system|J-domain containing HSP70 cochaperone` and `ER proteostasis|Protein transport|SEC61 channel complex component`; **PN-node mapping:** J-cochaperone type mapped, ok_for_propagation_to_go, GO:0030544 (Hsp70 protein binding); translocon group GO:0005784 (Sec61 translocon complex); transport class GO:0015031 (protein transport).
- **Consistency:** Strong agreement. Deep research, notes, and review YAML all frame SEC63 as a translocon-accessory DnaJ/Hsp40 J-domain co-chaperone that recruits/stimulates ER Hsp70 BiP (HSPA5) via its luminal J-domain (HPD/H132) to gate Sec61 and drive translocation. PN's dual placement (HSP70-system J-cochaperone + SEC61 component) exactly matches the review's two core_functions. No contradictions.
- **PN story / NEW pressure:** PN asserts a role NOT in existing GO annotations. SEC63 GOA has GO:0031207 (Sec62/Sec63 complex) and translocation BP terms, but NO molecular-function term for the J-domain/BiP co-chaperone activity. The review's own suggested_questions explicitly flags this gap. PN-projected GO:0030544 Hsp70 protein binding (verified real, def "Binding to a Hsp70 protein") precisely captures the J-domain-BiP interaction. Strong, defensible ADD. (GO:0051087 protein-folding chaperone binding is a verified broader alternative.) Conclude: ADD GO:0030544.
- **Mapping strategy:** Mapping is correct and is the gene that most justifies its node's MF. GO:0030544 is appropriately specific (not over-broad). Dossier `more_specific_than_existing_goa` is accurate (no MF chaperone term in GOA). GO:0005784 translocon CC is also defensible (TRAP-inclusive def); note SEC63 already has the narrower GO:0031207. No mapping change needed.
- **Evidence alignment:** PN rows carry no reference titles, but the review's BiP/J-domain evidence (PMID:29719251, 36459117, 32133789; SUBUNIT/DOMAIN/H132 mutagenesis) and the falcon deep research (shao2023, sun2022, schorr2019) fully support the PN J-cochaperone claim. Congruent; no divergence.
- **Verdict:** CONSISTENT; PN supplies the strongest NEW-term signal of the set (Hsp70 binding MF missing from GOA).
- **Recommended edits:** [YAML] Add MF GO:0030544 Hsp70 protein binding (enables; J-domain stimulation of BiP/HSPA5) to SEC63 existing_annotations + core_functions, supported by H132/HPD mutagenesis and PMID:29719251/36459117. [YAML] Optionally add GO:0005784 Sec61 translocon complex CC to mirror the PN node.