## CALR
- **UniProt:** P27797 · **batch:** proteostasis-batch-2026-06-06 · **review status:** COMPLETE (exhaustive; ~80 annotations, notes + falcon deep-research present)
- **PN placement:** `ER proteostasis|Glycoproteostasis|N-glycosylation system|Lectin chaperone` ; **PN-node mapping:** type (Lectin chaperone)→no_mapping; group (N-glycosylation system)→GO:0006487 protein N-linked glycosylation (mapped/ok_for_propagation); class/branch→no_mapping. (Identical node + mapping to CANX, its membrane-bound paralog.)
- **Consistency:** Biology consistent across review, notes, deep-research, and PN — calreticulin is the soluble ER-luminal lectin chaperone of the CNX/CRT cycle binding monoglucosylated N-glycans, also the major ER Ca2+ buffer and an MHC-I PLC component. As with CANX, the PROJECTED GO term conflicts with this role.
- **PN story / NEW pressure:** GO:0006487 (VERIFIED real) = the process of ADDING the N-glycan; calreticulin binds the pre-formed glycan, it is not a glycosyltransferase. The review correctly represents function as GO:0030246 carbohydrate binding (ACCEPT), GO:0044183 protein folding chaperone, GO:0006457 protein folding, GO:0036503 ERAD, plus Ca2+ binding and MHC-I PLC roles. GO:0006487 absent from CALR GOA (confirmed). Conclude: OVER-REACHES — same category error as CANX; do NOT add.
- **Mapping strategy:** Same fix as CANX — the lectin-chaperone members of the "N-glycosylation system" group should not inherit the enzymatic GO:0006487; the "Lectin chaperone" type node should carry a binding/chaperone mapping instead. This is one shared correction covering both CALR and CANX.
- **Evidence alignment:** PN node carries no reference titles; review well-evidenced (PMID:15474971 review, PMID:35948544 PLC structure, PMID:17563366 insulin-receptor chaperoning, PMID:10358038 surface CALR). Review also flags two wrong-gene reference mis-assignments at source (PMID:21705382→Bcl2l10; PMID:21590275→CALR3) — unrelated to the PN mapping but worth noting for REF hygiene. No shared evidence supports an N-glycosylation-process claim.
- **Verdict:** OVER-REACHES — reject projected GO:0006487 for CALR (true lectin-chaperone function already captured). **Recommended edits:** [MAP] do not propagate GO:0006487 to CALR; re-map the shared "Lectin chaperone" type node to a binding/chaperone term (GO:0030246 / GO:0036503), covering CALR+CANX together.