{"doi":"10.17615/4rpk-rb22","title":"mRNA Display Design of Fibronectin-based Intrabodies That Detect and Inhibit Severe Acute Respiratory Syndrome Coronavirus Nucleocapsid Protein","abstract":"The nucleocapsid (N) protein of severe acute respiratory syndrome (SARS) coronavirus plays important roles in both viral replication and modulation of host cell processes. New ligands that target the N protein may thus provide tools to track the protein inside cells, detect interaction hot spots on the protein surface, and discover sites that could be used to develop new anti-SARS therapies. Using mRNA display selection and directed evolution, we designed novel antibody-like protein affinity reagents that target SARS N protein with high affinity and selectivity. Our libraries were based on an 88-residue variant of the 10th fibronectin type III domain from human fibronectin (10Fn3). This selection resulted in eight independent 10Fn3 intrabodies, two that require the N-terminal domain for binding and six that recognize the C terminus, one with Kd = 1.7 nm. 10Fn3 intrabodies are well expressed in mammalian cells and are relocalized by N in SARS-infected cells. Seven of the selected intrabodies tested do not perturb cellular function when expressed singly in vivo and inhibit virus replication from 11- to 5900-fold when expressed in cells prior to infection. Targeting two sites on SARS-N simultaneously using two distinct 10Fn3s results in synergistic inhibition of virus replication.","journal":"UNC Libraries","year":2020,"id":117681,"datarank":0.0,"base_score":0.0,"endowment":0.0,"self_citation_contribution":0.0,"citation_network_contribution":0.0,"self_endowment_contribution":0.0,"citer_contribution":0.0,"corpus_percentile":null,"corpus_rank":null,"citation_count":1,"citer_count":0,"citers_with_citation_signal":0,"citers_with_endowment":0,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":0.9556,"is_data_producer":false,"deposit_databanks":null,"is_oa":true,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":"2020-01-01","fair_score":null,"fair_percentile":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":451187,"name":"Richard W. Roberts","orcid":"0000-0002-8587-5097","position":1,"is_corresponding":false},{"id":433766,"name":"C. Anders Olson","orcid":"0000-0002-5382-1393","position":2,"is_corresponding":false},{"id":548981,"name":"Hsiang-I Liao","orcid":null,"position":3,"is_corresponding":false},{"id":107930,"name":"Ren Sun","orcid":"0000-0002-8628-7019","position":4,"is_corresponding":false},{"id":5952,"name":"Ralph S. Baric","orcid":"0000-0001-6827-8701","position":5,"is_corresponding":false},{"id":548982,"name":"Elaine Wong","orcid":null,"position":6,"is_corresponding":false},{"id":544129,"name":"Hongyu Deng","orcid":"0000-0001-6703-6313","position":7,"is_corresponding":false},{"id":347859,"name":"Seungmin Hwang","orcid":"0000-0003-0846-5462","position":0,"is_corresponding":true}],"reference_count":0,"raw_metadata":null,"created_at":"2026-07-18T23:13:54.951170Z","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":[]}