id: Q9VQ04
gene_symbol: CG5565
taxon:
  id: NCBITaxon:7227
  label: Drosophila melanogaster
status: COMPLETE
description: The ProtNLM2 API snapshot retrieved 2026-09-08 contains no GO-term predictions for Q9VQ04.
  Phosphatase activity (GO:0016791) is a supported omission candidate; pseudouridine 5'-phosphatase activity
  (GO:1990738) is a more specific candidate supported by FlyBase's manual ortholog transfer to experimentally
  characterized human PUDP, together with near-complete sequence alignment and retained catalytic Asp
  positions. The substrate assignment is an orthology-based inference, not a direct CG5565 assay; the
  alignment alone does not establish substrate specificity. The separate FUNCTION claim of in-vitro D,L-glyceraldehyde
  3-phosphate dephosphorylation remains UNC and is not disproved by the better-supported physiological
  substrate. This completed record assesses the absence of GO output; predictions is empty because no
  GO or EC prediction was emitted. The narrative judgment remains in the linked function review and is
  not a score assigned to the omission.
source_documents:
- genes/DROME/CG5565/CG5565-protnlm-source.json
- projects/PROTNLM_EVALUATION/fly-benchmark/manifest.json
- genes/DROME/CG5565/CG5565-protnlm-function-review.md
- genes/DROME/CG5565/CG5565-uniprot.txt
- genes/DROME/CG5565/CG5565-bioinformatics/RESULTS.md
- publications/PMID_20722631.md
references:
- id: file:DROME/CG5565/CG5565-uniprot.txt
  title: CG5565 UniProt annotation record
  findings:
  - statement: FlyBase records an ISS pseudouridine 5'-phosphatase assignment.
    supporting_text: DR   GO; GO:1990738; F:pseudouridine 5'-phosphatase activity; ISS:FlyBase.
- id: file:DROME/CG5565/CG5565-bioinformatics/RESULTS.md
  title: CG5565 comparison with human PUDP
  findings:
  - statement: The target aligns across almost all human PUDP residues and retains the mapped catalytic
      Asp positions.
    supporting_text: The native 240-residue CG5565 protein aligns across 226 of 228 human PUDP/Q08623
      residues, with 98 identical aligned positions (43.4% of aligned pairs). Human annotated catalytic
      Asp14 and Asp16 map to target Asp16 and Asp18.
- id: PMID:20722631
  title: HDHD1, which is often deleted in X-linked ichthyosis, encodes a pseudouridine-5'-phosphatase.
  findings:
  - statement: Purified human HDHD1/PUDP strongly prefers pseudouridine 5'-phosphate among the tested
      phosphate esters; this is the characterized ortholog evidence.
    supporting_text: 'Purified human

      recombinant HDHD1 dephosphorylated pseudouridine 5''-phosphate with a kcat of 1.6

      s-1, a Km of 0.3 μM and a catalytic efficiency at least 1000-fold higher than

      that on which it acted on other phosphate esters, including 5''-UMP.'
  full_text_unavailable: true
predictions: []