## SPCS2
- **UniProt:** Q15005 (SPC25) · **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 SPCS2 as a non-catalytic accessory SPC subunit that enhances complex activity and shapes substrate/cleavage-site selection (yeast Spc2 ortholog; membrane-thinning). PN node correctly captures complex membership without ascribing catalysis. No contradictions.
- **PN story / NEW pressure:** Same pattern as SPCS1. PN asserts CC membership (GO:0005787, already in review IBA/IEA/IPI) and the broad transport class (GO:0015031). The review deliberately MODIFIES IBA GO:0045047→GO:0006465 (signal peptide processing), arguing SPCS2 acts after targeting. So the PN GO:0015031 protein transport projection slightly over-reaches; GO:0006465 is the accurate BP. No new MF (non-catalytic; "enhances enzymatic activity" is a regulatory/architectural role, not a catalytic MF). Conclude: membership already captured; transport-class projection over-reaches.
- **Mapping strategy:** GO:0005787 CC mapping correct. GO:0015031 protein transport is the questionable class projection for accessory subunits; review's GO:0006465 signal peptide processing is more defensible. Node should distinguish accessory (architecture/selectivity, GO:0006465) from catalytic (GO:0009003) members rather than flattening all four to one CC + protein-transport BP.
- **Evidence alignment:** PN row carries no titles; review's structural/mechanistic evidence (PMID:34388369; PMID:39565596 yeast Spc2 substrate/cleavage-site selection, explicitly cross-referenced to human SPCS2) plus host-pathogen context (PMID:34232536, 36789796, 38230952) and falcon deep research (chung2024, kozono2023) all converge. Congruent.
- **Verdict:** CONSISTENT on membership; PN's protein-transport class projection over-reaches (review's GO:0006465 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). Optionally [REF] note PMID:39565596 (Spc2/SPCS2 substrate-selection) supports a substrate-selectivity contribution beyond bare membership.