## EMC8
- **UniProt:** O43402 · **batch:** proteostasis-batch-2026-06-11 · **review status:** COMPLETE
- **PN placement:** `ER proteostasis|Protein transport|Transmembrane protein import|EMC complex component` ; **PN-node mapping:** type → GO:0072546 (EMC complex); group → GO:0044743 (protein transmembrane import into intracellular organelle); class → GO:0015031 (protein transport); branch=no_mapping.
- **Consistency:** Deep research, review YAML, and PN annotation agree: EMC8 is a cytosolic, non-catalytic accessory subunit docking on the EMC2 scaffold; mutually exclusive with paralog EMC9 (PMID:32459176). Degenerate MPN domain, no catalytic metalloprotease residues. The review adds an EMC8-specific client-docking ("Cyto dock"/CaVbeta3) chaperone surface (PMID:37196677) beyond the dossier; no contradiction.
- **PN story / NEW pressure:** PN asserts only EMC membership + transmembrane import/insertion, already captured (GO:0072546 part_of; GO:0032977 contributes_to; GO:0045050, GO:0071816 involved_in). No NEW term warranted. The EMC8-specific CaVbeta3 chaperone/assembly surface could in principle motivate a chaperone MF, but the review (appropriately) leaves it as descriptive, not a new annotation — defensible.
- **Mapping strategy:** EMC8 does not change the shared node mapping; its EMC8/EMC9 mutual exclusivity makes both still "EMC complex" members, so GO:0072546 stands. Same group-level concern as EMC7: GO:0044743 (lumenal import) mismatches EMC membrane-protein *insertion* semantics (insertion terms are not subclasses of it).
- **Evidence alignment:** High overlap — review and PN both rest on the EMC insertase/structure papers (22119785, 29242231, 32439656, 30415835, 32459176, 35287476). PN process claim is fully evidenced in the review.
- **Verdict:** Consistent; thoroughly reviewed (incl. correct contributes_to for non-catalytic subunit). Only shared concern: group→GO:0044743 import mapping diverges from EMC insertion semantics.