Identity: ulp2, UniProt O13769; current PomBase systematic identifier is recorded in the benchmark cohort. The UniProt sequence is the reviewed current record, whereas the source XML uses placeholder taxonomy and sequence fields. Those placeholders are not biological evidence.
Source: PRE-RELEASE post-processed-2026_02_28k.xml. The exact entry is in ulp2-protnlm-source.xml. No entry belongs to the published 26,856-record pilot list. Current API availability does not change the original source version.
The XML evidence keys, model scores, string-match hydration metadata and alignment accessions/scores are retained verbatim in that source file. Assessments use current sequence features and primary sources; annotation overlap and ARBA output do not independently validate a prediction.
LSP: Purified fission-yeast Ulp2 directly deconjugates SUMO from high-molecular-weight species, and the study identifies it as a cysteine protease. SUMO is a ubiquitin-like modifier, so the broad ubiquitin-like protein peptidase term is biologically correct. The more specific deSUMOylase activity GO:0016929 is experimentally established and already annotated; the XML records hydration from that term. This prediction loses substrate specificity and is therefore LSP. It does not imply a demonstrated ability to remove ubiquitin itself.
LSP: Direct biochemical experiments establish Ulp2 as a SUMO-deconjugating cysteine protease, including sensitivity to N-ethylmaleimide. The conserved C48 catalytic domain is consistent with that mechanism. Cysteine-type peptidase activity is true but less precise than the already annotated deSUMOylase activity and its SUMO substrate specificity. The XML keyword hydration does not supply independent validation; the target biochemical result does.
QuickGO GO:0070139 (SUMO-specific endopeptidase activity), accessed 2026-09-08: "Catalysis of the hydrolysis of peptide bonds between an alpha-carboxyl group and an alpha-amino group within the small conjugating protein SUMO.". The frozen JSON is adjacent to this file.
The full text of PMID:24818994(https://pubmed.ncbi.nlm.nih.gov/24818994/), DOI 10.1371/journal.pone.0094182, separates precursor maturation from deconjugation. Figure 1 compares full-length SUMO processing by Ulp1 and Ulp2, then tests high-molecular-weight SUMO conjugates in pombe extracts with increasing Ulp2 amounts and an NEM-treated enzyme control. These experiments establish deSUMOylation more specifically than either external peptidase prediction. Reduced precursor-processing efficiency is not a demonstration of absolute inability to process precursor SUMO.
The eIF4G/eIF3h interactions do not make Ulp2 a constitutive translating-ribosome component. The discussion reports that Ulp2 remained in large sedimenting complexes when EDTA disrupted polysomes. Its stress and translation-factor associations therefore should not be treated as evidence for ribosomal residence or an intrinsic translation activity. This is the same primary study used in the review, not an additional experimental replication.
The original Falcon request completed after 1295.37 seconds (about 21.6 minutes), despite the wrapper reporting a 600-second timeout and the fallback failing with quota HTTP401. The returned provider report and its artifact were retained unchanged and inspected. No duplicate request was made.
The report agrees with the primary biochemical and localization evidence already used here: Ulp2 is predominantly a SUMO-deconjugating cysteine protease in intranuclear foci, with substantially weaker SUMO-precursor processing than Ulp1. Its eIF4G discussion correctly distinguishes co-purification and eIF4G sumoylation from direct Ulp2-dependent substrate turnover. It supplies no evidence resolving the specific stress-granule or translation-regulation assertions. Both external broad peptidase predictions therefore remain LSP.
The additional 2016 primary source was verified and cached in full: PMID:27398807, Functional Crosstalk between the PP2A and SUMO Pathways Revealed by Analysis of STUbL Suppressor, razor 1-1. The Ulp2-relevant results support genetic suppression and altered SUMO-conjugate abundance: PMID:27398807. This strengthens SUMO-homeostasis context without changing modifier specificity, localization or the existing GO judgments.
The STUbL relationship must remain genotype-dependent rather than being reduced to two interchangeable routes that prevent SUMO accumulation. The primary paper explicitly states PMID:27398807. Neither the generated synthesis nor this genetic relationship identifies a direct Ulp2-STUbL complex or a shared named substrate. No biological YAML changes were warranted by the late report.