USP8: ProtNLM function-description review

Finding: Supported conserved deubiquitinase function.

Target: A0A9L0T7K6, Equus caballus. The exact source is the frozen ProtNLM API response dated 2026-09-08, retained in projects/PROTNLM_EVALUATION/mammal-benchmark/predictions.jsonl.gz.

Original prediction

Deubiquitinating enzyme that removes conjugated ubiquitin from specific proteins to regulate different cellular processes

Atomic claims

Removes conjugated ubiquitin from proteins

Supported. Recombinant and immunoprecipitated human UBPY/USP8 cleave linear and isopeptide-linked ubiquitin chains (PMID:9628861). The selected horse protein retains the USP8 catalytic architecture with 91.82% paired sequence identity across 99.46% of the human reference.

Regulates different cellular processes through selected substrates

Supported at this broad level. Human studies connect USP8 to endosomal sorting, EGFR trafficking and substrate stability. This broad wording does not assert a particular horse-specific substrate or disease phenotype.

Evidence and limits

Existing horse GOA already includes cysteine-type deubiquitinase activity and protein deubiquitination. Deubiquitination can participate in ubiquitin-dependent catabolism by controlling cargo sorting; a deubiquitinase label alone does not refute the accompanying catabolic-process GO prediction. Training membership is unknown.

The reproducible paired sequence comparison records residue-level findings and sequence hashes. The human UniProt source distinguishes experimental supporting papers from inferred statements. ARBA assertions and generated review prose are not used as validating evidence.