Selected accession A0A9L0S5Z5; ordinary UniProt record is TrEMBL and cites genome sequencing/submission rather than a gene-specific functional experiment. Human evidence is summarized in the paired human investigation. Sequence comparison records the exact target gaps and transfer limits. The targeted Europe PMC search found no decisive gene-specific horse functional assay warranting a separate horse Edison investigation; general omics/association hits were not counted as mechanistic validation.
Apg2/HSPA4 belongs to the Hsp110 branch of the Hsp70 superfamily. Human biochemical work measures its effect on the Hsc70 ATPase cycle, aggregate binding and refolding. The concentration dependence is important: low Apg2 stimulates the system, while high concentrations can inhibit it. Its acidic and C-terminal regions regulate association and exchange. Those studies do not make HSPA4 the Hsp70L1 subunit of the Mpp11/Hsp70L1 ribosome-associated complex. General chaperone activity is transferable at a broader level than membership of a specific ribosome-bound assembly. A Tom40-import annotation must be checked in the complete original paper, since its abstract emphasizes Hsp90 rather than resolving every chaperone tested.
Sources: PMID:30521813(https://pubmed.ncbi.nlm.nih.gov/30521813/), PMID:36167183(https://pubmed.ncbi.nlm.nih.gov/36167183/), PMID:36604744(https://pubmed.ncbi.nlm.nih.gov/36604744/), PMID:15644312(https://pubmed.ncbi.nlm.nih.gov/15644312/).