Short verdict: Keep. The interaction-tethering metaphor is useful, but SUMO also changes activity, localization, stability, and stress responses.
What the current graph claims
Node definition: SUMOylation by SAE/UBC9/PIAS systems altering protein interactions, nuclear bodies, repression, DNA repair, and STUbL-mediated ubiquitination.
What is strongly supported: SUMO modifies many nuclear proteins and recruits SIM-containing partners; SUMO-targeted ubiquitin ligases connect SUMO to ubiquitin turnover.
What is context-dependent: SUMO1 versus SUMO2/3 chains, stress induction, and substrate-site context matter; many SUMO effects are transient and substoichiometric.
What is weak, controversial, or assay-biased: Proteomics can identify many SUMO sites with uncertain function; assigning repression to SUMO broadly is overgeneralized.
What may be duplicate biology under another name: Overlaps with ROUTER and PAR/DNA repair.
Missing or excessive graph structure
Missing edges: Add TETHER -> PAR/DNA repair or TETHER -> KEYS? SUMO strongly affects transcription factors and repair foci but map may stay simple.
Excess edges: TETHER -> ROUTER via STUbL is accurate but should be context-specific/dashed.
Candidate splits: No split.
Candidate merges: No merge.
Candidate renames: SUMO.
Recommendation
Concrete graph change, if any: Keep; broaden beyond repression/tethering and caveat functional proteomics.
Concrete technical-notes/blog wording change, if any: Mirror the graph recommendation in the glossary and relation catalogue, and explicitly mark the confidence/caveat where the claim is context-dependent or assay-sensitive.
Key sources
PMID 26542802 — SUMOylation mechanisms and cellular regulation review.
PMID 29540635 — SUMO in DNA repair and nuclear organization review.
PMID 25527682 — SUMO-targeted ubiquitin ligases connecting SUMO to ubiquitin.
PMID 33128053 — SUMO proteomics and functional interpretation review.