HSP20A

Review rationale: The target is a full-length small heat-shock protein with an alpha-crystallin domain. The PTHR11527 family-root PAINT node PTN000163021 carries response to salt stress, and the closest placed relative of B7FXQ8 is a Thalassiosira pseudonana PTHR11527:SF175 sHSP. The family-root salt IBD rests on stimulus-specific plant phenotypes, and no salt induction, protection or loss-of-function data exist for B7FXQ8 or any characterised protein in its diatom lineage. The gene review treats this IBD as an open question rather than transferring it, and the OpenScientist analysis flags the salt prediction as an outlier relative to the family's InterPro2GO mapping. Characterised sHSP client binding (PMID:29983375) does not establish a salt-triggered response. The term is absent from GOA for this gene, and the prediction can neither be supported nor refuted.

Review rationale: B7FXQ8 is a full-length sHSP with a complete alpha-crystallin domain and retains the C-terminal I-X-I oligomer-assembly motif (IAI, residues 150-152). Protein complex oligomerization is a PAINT IBD at the PTHR11527 family root PTN000163021, from which the diatom SF175 sHSPs that group with B7FXQ8 descend, and oligomer assembly is demonstrated experimentally for sHSPs such as archaeal Hsp16.5 (PMID:29983375). This is a justified family-level inference, not an observation on the target, and it does not fix an oligomer size. The gene review proposes this process as a new annotation. B7FXQ8 has no GOA annotations, so the prediction is novel.

Review rationale: Protein folding is among the PAINT IBDs at the PTHR11527 family root, and characterised sHSPs bind non-native clients and suppress their aggregation (PMID:29983375), which can feed into ATP-dependent refolding by other chaperones. The re-reviewed gene and its bioinformatic analysis limit transfer to holdase client binding, oligomerization and response to heat, and treat sHSPs as holdases that do not themselves assist folding; the PTHR11527 family review leaves the protein-folding process unresolved. No folding, refolding or aggregation assay exists for B7FXQ8 or any protein in its diatom lineage. The term is absent from GOA for this gene. Whether holdase activity amounts to participation in protein folding for this protein is not settled by the available evidence.

Review rationale: Response to heat is a PAINT IBD at the PTHR11527 family root PTN000163021, and in an alpha- crystallin-domain tree B7FXQ8 groups with a Thalassiosira pseudonana PTHR11527:SF175 sHSP that descends from that node. B7FXQ8 is a full-length member with a complete alpha-crystallin domain, and characterised sHSPs bind unfolded clients (PMID:29983375), the mechanism by which they hold heat- denatured proteins. The gene review proposes response to heat as a new annotation on this basis. The support is a phylogenetic transfer; no heat-induction or thermotolerance data exist for B7FXQ8 itself. B7FXQ8 has no GOA annotations, so the prediction is novel.

Review rationale: The small-HSP architecture supports a holdase chaperone role, and response to hydrogen peroxide is a PAINT IBD at the PTHR11527 family root. That IBD rests on stimulus-specific phenotypes in other branches, and the gene review leaves its family-wide applicability as an open question rather than transferring it. No peroxide induction, protection or perturbation data exist for B7FXQ8 or a characterised protein in its diatom lineage, and the OpenScientist analysis flags the peroxide prediction as an outlier. The term is absent from GOA for this gene and can neither be supported nor refuted.

Review rationale: B7FXQ8 has the complete alpha-crystallin domain and I-X-I motif of small heat-shock proteins. Client-binding experiments on characterised sHSPs show recognition of partially or globally unfolded proteins (PMID:29983375), and the gene review's core function is an ATP-independent holdase that binds non-native clients. This supports the binding claim as a family-level inference. GO:0051082 is obsolete in the current ontology without a replacement; the gene review records the activity under a proposed holdase chaperone term. The biological claim is correct, but the term is unusable for a live annotation. B7FXQ8 has no GOA annotations, so the claim is novel.