## SPCS1
- **UniProt:** Q9Y6A9 (SPC12) · **batch:** proteostasis-batch-2026-06-11 · **review status:** COMPLETE
- **PN placement:** `ER proteostasis|Protein transport|ER signal peptidase`; **PN-node mapping:** group mapped, ok_for_propagation_to_go, GO:0005787 (signal peptidase complex); class GO:0015031 (protein transport).
- **Consistency:** Strong agreement. Deep research, review YAML, and PN all describe SPCS1 as a non-catalytic accessory SPC subunit (multi-pass, cytosol-facing termini, dispensable for catalysis; contributes to membrane-thinning window/selectivity) plus a flavivirus/HCV host factor. PN node correctly captures complex membership without ascribing catalysis. No contradictions.
- **PN story / NEW pressure:** PN asserts only CC membership (GO:0005787) and broad transport (GO:0015031). GO:0005787 already in review (IBA/IEA/IPI/TAS). The transport class GO:0015031 is broader than the review, which deliberately MODIFIES the IBA GO:0045047 (protein targeting to ER) to GO:0006465 signal peptide processing — i.e. the review argues SPCS1 acts downstream of targeting, not in transport. So PN's GO:0015031 (protein transport) projection slightly over-reaches for an accessory peptidase subunit. The accurate process is GO:0006465. No new MF justified (non-catalytic). Conclude: membership already captured; PN transport-class projection over-reaches vs review's signal-peptide-processing framing.
- **Mapping strategy:** GO:0005787 CC mapping is correct. The class-level GO:0015031 protein transport is the questionable projection: for accessory SPC subunits the review's signal peptide processing (GO:0006465) is the defensible BP, and protein transport over-states an upstream-transport role SPCS1 does not have (parallels the broader-than-warranted precedent). Suggest the node distinguish accessory (membership/selectivity, GO:0006465) from catalytic members.
- **Evidence alignment:** PN row carries no titles; review's accessory/topology evidence (PMID:8632014, PMID:34388369) and viral host-factor evidence (PMID:24009510, 27383988, 29593046, 35130329, 33577859) plus falcon deep research (liaci2021, chung2024) all converge. Congruent.
- **Verdict:** CONSISTENT on membership; PN's protein-transport class projection over-reaches (review's GO:0006465 signal peptide processing is more accurate). No gene-YAML edit needed.
- **Recommended edits:** [MAP] At the "ER signal peptidase" class, prefer GO:0006465 signal peptide processing over GO:0015031 protein transport as the BP projection for accessory subunits (SPCS1/2), reflecting that SPCS1 acts downstream of ER targeting (matches review MODIFY of GO:0045047→GO:0006465).