{"doi":"10.1101/2021.04.28.441858","title":"The YΦ Motif Defines the Structure-Activity Relationships of Human 20S Proteasome Activators","abstract":"The 20S proteasome (20S) facilitates turnover of most eukaryotic proteins. Substrate entry into the 20S first requires opening of gating loops through binding of HbYX motifs that are present at the C-termini of certain proteasome activators (PAs). The HbYX motif has been predominantly characterized in the archaeal 20S, whereas little is known about the sequence preferences of the human 20S ( h 20S). Here, we synthesized and screened ∼120 HbYX-like peptides, revealing unexpected differences from the archaeal system and defining the h 20S recognition sequence as the Y-F/Y (YΦ) motif. To gain further insight, we created a functional chimera of the optimized sequence, NLSYYT, fused to the model activator, PA26 E102A .A cryo-EM structure of PA26 E102A - h 20S identified key interactions, including non-canonical contacts and gate-opening mechanisms. Finally, we demonstrated that the YΦ sequence preferences are tuned by valency, allowing multivalent PAs to sample greater sequence space. These results expand the model for termini-mediated gating and provide a template for the design of h 20S activators.","journal":"bioRxiv (Cold Spring Harbor Laboratory)","year":2021,"id":218683,"datarank":0.16479184330021646,"base_score":1.0986122886681096,"endowment":1.0986122886681096,"self_citation_contribution":0.16479184330021646,"citation_network_contribution":0.0,"self_endowment_contribution":0.16479184330021646,"citer_contribution":0.0,"corpus_percentile":null,"corpus_rank":null,"citation_count":2,"citer_count":0,"citers_with_citation_signal":0,"citers_with_endowment":0,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":0.962,"is_data_producer":false,"deposit_databanks":null,"is_oa":true,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":"2021-01-01","fair_score":null,"fair_percentile":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":816488,"name":"Andres H. de la Peña","orcid":"0000-0002-2368-6944","position":1,"is_corresponding":false},{"id":816489,"name":"Sarah K. Williams","orcid":"0000-0002-3737-9785","position":2,"is_corresponding":false},{"id":816787,"name":"Nikita Chopra","orcid":null,"position":3,"is_corresponding":false},{"id":91660,"name":"Andrej Săli","orcid":"0000-0003-0435-6197","position":4,"is_corresponding":false},{"id":287919,"name":"Gabriel C. Lander","orcid":"0000-0003-4921-1135","position":5,"is_corresponding":false},{"id":275686,"name":"Jason E. Gestwicki","orcid":"0000-0002-6125-3154","position":6,"is_corresponding":false},{"id":816487,"name":"Kwadwo Opoku-Nsiah","orcid":"0000-0002-4059-9746","position":0,"is_corresponding":true}],"reference_count":64,"raw_metadata":{"citation_network_status":"fetched"},"created_at":"2026-07-18T23:53:29.626149Z","pmid":null,"pmcid":null,"fwci":null,"citation_percentile":null,"influential_citations":0,"oa_status":null,"license":null,"views":0,"total_file_size_bytes":0,"version_count":0,"fair_f":null,"fair_a":null,"fair_i":null,"fair_r":null,"fair_zscore":null,"fair_rationale":null,"fair_model":null,"fair_agent_version":null,"fair_fulltext_source":null,"fair_has_llm":null,"fair_computed_at":null,"clinical_trials":[],"software_tools":[],"db_accessions":[],"linked_datasets":[],"topics":[]}