id: Q8IP30
gene_symbol: CG4793
taxon:
  id: NCBITaxon:7227
  label: Drosophila melanogaster
status: COMPLETE
description: The intrinsic serine-type endopeptidase prediction is contradicted by loss of the catalytic
  serine in the exact Q8IP30 protease-like domain. CG4793 has experimentally supported immune-regulatory
  biology, but its direct molecular mechanism is unresolved.
source_documents:
- projects/PROTNLM_EVALUATION/fly-benchmark/predictions.jsonl.gz
- genes/DROME/CG4793/CG4793-bioinformatics/Q8IP30-predictions.json
- genes/DROME/CG4793/CG4793-bioinformatics/Q8IP30-uniprot.json
- genes/DROME/CG4793/CG4793-bioinformatics/RESULTS.md
references:
- id: file:DROME/CG4793/CG4793-bioinformatics/RESULTS.md
  title: CG4793 catalytic-site and exact-sequence analysis
  findings: []
- id: PMID:33644706
  title: The S1A protease family members CG10764 and CG4793 regulate cellular immunity in Drosophila.
  full_text_unavailable: false
  findings: []
predictions:
- source_method: ProtNLM2
  source_version: UniProt API snapshot 2026-09-08
  source_reference_id: file:DROME/CG4793/CG4793-bioinformatics/Q8IP30-predictions.json
  predicted_term:
    id: GO:0004252
    label: serine-type endopeptidase activity
  predicted_term_type: GO_MF
  review:
    assessment: NPI
    confidence_score: 0
    error_type: PSEUDOENZYME_OVERANNOTATION
    summary: The exact 910-residue Q8IP30 sequence has a protease-like domain with glycine replacing the
      catalytic serine, supported by substantial-coverage alignments to two active trypsin controls. The
      controls agree on the additional His-to-Glu and Asp-to-Asn site mappings, although the histidine
      region is more divergent. These residue observations, rather than the SPH name or an automated domain
      caution alone, refute conventional serine endopeptidase catalysis. Four existing GOA NOT annotations
      are concordant negative annotations, not evidence that the positive prediction is correct or non-novel.
      The source gives model score 0.99 and phmmer donor Q7Z410 with score 226.0; donor similarity cannot
      restore the missing nucleophile. Gene-specific RNAi establishes cellular immune regulation, without
      assaying purified-protein proteolysis or resolving a direct mechanism.
    supported_by:
    - reference_id: file:DROME/CG4793/CG4793-bioinformatics/RESULTS.md
      supporting_text: Global domain alignments to active trypsins P00760 and P00761 map the catalytic
        His, Asp and Ser to Q8IP30 Glu145, Asn191 and Gly290, respectively. In particular, the catalytic
        serine is replaced by glycine in the conserved local segment TCKGDGGAPLA.
    - reference_id: PMID:33644706
      supporting_text: CG4793 is an SPH gene and encodes a protein that is predicted to be catalytically
        inactive.