## HSPB2
- **UniProt:** Q16082 (MKBP) · **batch:** proteostasis-batch-2026-06-07b · **review status:** COMPLETE
- **PN placement:** two rows — `Cytonuclear proteostasis|Chaperone|small HSP system|small HSP` (type=mapped) and `Mitochondrial proteostasis|Chaperone|small HSP` (group=mapped); **PN-node mapping:** both → GO:0044183 protein folding chaperone, scope=ok_for_propagation_to_go, projected new_to_goa; class/branch=no_mapping.
- **Consistency:** Largely consistent. Deep research, notes, and review YAML agree HSPB2 is an ATP-independent small HSP (alpha-crystallin/HSP20) holdase (core MF GO:0051082 unfolded protein binding; validated client GAPDH, PMID:26465331) and a DMPK kinase activator (core MF GO:0008047, PMID:9490724). PN "small HSP" placement matches. The CY+MI dual branch fits HSPB2's cytosolic muscle oligomers plus a cardiac mitochondrial-leaning interactome (PMID:26465331). No contradiction; note review REMOVES GO:0005212 (eye-lens crystallin) as an erroneous family transfer — a good catch the PN small-HSP node does not propagate.
- **PN story / NEW pressure:** PN asserts GO:0044183 protein folding chaperone (verified real). GOA lacks GO:0044183 (new_to_goa correct). GO:0044183 sits on the chaperone-ACTIVITY branch, sibling to the review's GO:0051082 (on the binding branch) — neither is ancestor of the other; both are defensible for a sHSP holdase. GO:0044183 is broader/coarser than the review's holdase-specific framing but not wrong. Reasonable ADD; not over-reaching for a bona fide sHSP.
- **Mapping strategy:** Node status unchanged. Projection accurate (term absent from GOA). GO:0044183 is appropriately generic for the "small HSP" type; the review's GO:0051082 + holdase (GO:0140309 territory) is the more precise gene-level call. Minor altitude divergence only.
- **Evidence alignment:** PN rows no titles; review anchors on PMID:9490724 (MKBP/DMPK, TAS) and PMID:26465331 (cardiac interactome/GAPDH client) — both VERIFIED. No conflict.
- **Verdict:** Consistent. GO:0044183 is a defensible new_to_goa ADD (broader sibling of review's GO:0051082, both valid for a sHSP holdase). DMPK-activator and lens-removal are gene-specific calls outside the PN family mapping.