id: A0A9L0S961
gene_symbol: PPP4R4
taxon:
  id: NCBITaxon:9796
  label: Equus caballus
status: COMPLETE
description: Phosphatase regulation and complex membership are supported by conserved PP4R4 biology; blastocyst
  hatching remains unverified.
source_documents:
- projects/PROTNLM_EVALUATION/mammal-benchmark/horse40-predictions.csv
- projects/PROTNLM_EVALUATION/mammal-benchmark/predictions.jsonl.gz
- projects/PROTNLM_EVALUATION/mammal-benchmark/paired-sequences/PPP4R4.json
references:
- id: PMID:18715871
  title: PP4R4/KIAA1622 forms a novel stable cytosolic complex with phosphoprotein phosphatase 4.
  full_text_unavailable: true
  findings: []
- id: file:HORSE/PPP4R4/PPP4R4-bioinformatics/RESULTS.md
  title: HORSE/PPP4R4/PPP4R4-bioinformatics/RESULTS.md
  findings: []
predictions:
- source_method: ProtNLM2
  source_version: UniProt API snapshot 2026-09-08
  predicted_term:
    id: GO:0001835
    label: blastocyst hatching
  predicted_term_type: GO_BP
  review:
    assessment: UNC
    confidence_score: 1
    summary: The primary human PP4R4 study establishes a cytosolic PP4 complex and altered phosphatase
      activity, not an embryonic hatching function. A nearly full-length horse homolog supports transfer
      of the molecular complex role but does not by itself establish this specific developmental process.
      Gene-specific embryo evidence or a traced functional mechanism is needed; absence of such evidence
      is not proof that the process is impossible.
    supported_by:
    - &id001
      reference_id: PMID:18715871
      supporting_text: "we identify \na novel, stable cytosolic PP4c interacting partner, KIAA1622, which\
        \ we have \nrenamed PP4R4."
    - reference_id: file:HORSE/PPP4R4/PPP4R4-bioinformatics/RESULTS.md
      supporting_text: share 95.0% identity among 865 paired residues. Paired coverage is 99.1% of human
        and 100.0% of horse.
- source_method: ProtNLM2
  source_version: UniProt API snapshot 2026-09-08
  predicted_term:
    id: GO:0019888
    label: protein phosphatase regulator activity
  predicted_term_type: GO_MF
  review:
    assessment: COR
    confidence_score: 2
    summary: Human PP4R4 is an experimentally isolated stable cytosolic partner of PP4c and changes the
      activity of the complex. The selected horse protein is 95.0% identical across nearly the entire
      human sequence with no large domain deletion, supporting conserved complex membership and regulatory
      function. These claims are new relative to the frozen horse GOA; human evidence is not claimed to
      be absent from model training.
    supported_by:
    - *id001
    - reference_id: PMID:18715871
      supporting_text: "PP4c.PP4R4 complexes exhibit phosphatase activity toward a \nfluorogenic substrate\
        \ and gammaH2AX, but this activity is lower than that \nassociated with the PP4c.PP4R2.PP4R3 complex,\
        \ which itself is less active than \nthe free PP4c catalytic subunit."
    - reference_id: file:HORSE/PPP4R4/PPP4R4-bioinformatics/RESULTS.md
      supporting_text: share 95.0% identity among 865 paired residues. Paired coverage is 99.1% of human
        and 100.0% of horse.
- source_method: ProtNLM2
  source_version: UniProt API snapshot 2026-09-08
  predicted_term:
    id: GO:0008287
    label: protein serine/threonine phosphatase complex
  predicted_term_type: GO_CC
  review:
    assessment: COR
    confidence_score: 2
    summary: Human PP4R4 is an experimentally isolated stable cytosolic partner of PP4c and changes the
      activity of the complex. The selected horse protein is 95.0% identical across nearly the entire
      human sequence with no large domain deletion, supporting conserved complex membership and regulatory
      function. These claims are new relative to the frozen horse GOA; human evidence is not claimed to
      be absent from model training.
    supported_by:
    - *id001
    - reference_id: PMID:18715871
      supporting_text: "PP4c.PP4R4 complexes exhibit phosphatase activity toward a \nfluorogenic substrate\
        \ and gammaH2AX, but this activity is lower than that \nassociated with the PP4c.PP4R2.PP4R3 complex,\
        \ which itself is less active than \nthe free PP4c catalytic subunit."
    - reference_id: file:HORSE/PPP4R4/PPP4R4-bioinformatics/RESULTS.md
      supporting_text: share 95.0% identity among 865 paired residues. Paired coverage is 99.1% of human
        and 100.0% of horse.