{"doi":"10.1016/j.virol.2024.110258","title":"Avian deltacoronaviruses encode fusion-associated small transmembrane proteins that can induce syncytia formation","abstract":"Fusion-associated small transmembrane (FAST) proteins are nonstructural viral proteins that induce cell-cell fusion. FAST proteins, which previously were identified in the genomes of double-stranded RNA viruses, typically contain an acylated N-terminal ectodomain, central transmembrane domain, and C-terminal endodomain with a polybasic region. Using sequence homology and protein motif prediction, we identified accessory proteins in a subset of avian deltacoronaviruses as putative FAST proteins. Transient expression of thrush coronavirus NS7b or common moorhen coronavirus NS7a, but not night heron coronavirus NS7b, induced cell-cell fusion. Syncytia were detected in primate kidney epithelial cells or fibroblasts but not chicken embryo fibroblasts, and addition of an N-terminal FLAG peptide to the proteins ablated fusion activity. These findings suggest that multiple avian deltacoronaviruses, positive-sense RNA viruses, encode nonstructural proteins that can mediate cell-cell fusion and share features with known FAST proteins. Additional studies are needed to understand contributions of these proteins to deltacoronavirus biology. • A type of nonstructural viral fusogen has been found predominantly in dsRNA viruses • Avian deltacoronavirus accessory proteins share features with these fusogens • Expression of avian deltacoronavirus accessory proteins induces cell-cell fusion • Positive-sense RNA viruses encode nonstructural viral fusogens","journal":"Virology","year":2024,"id":477697,"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":2,"citer_count":0,"citers_with_citation_signal":0,"citers_with_endowment":0,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":0.9555,"is_data_producer":false,"deposit_databanks":null,"is_oa":true,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":"2024-01-01","fair_score":null,"fair_percentile":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":40791,"name":"Monique S. Porter","orcid":"0000-0002-5439-0273","position":1,"is_corresponding":false},{"id":1167298,"name":"Vanesa Veletanlic","orcid":null,"position":2,"is_corresponding":false},{"id":561881,"name":"Kristen M. Ogden","orcid":"0000-0002-2670-4335","position":3,"is_corresponding":false},{"id":1167299,"name":"Kylie Sartalamacchia","orcid":null,"position":0,"is_corresponding":true}],"reference_count":52,"raw_metadata":null,"created_at":"2026-07-19T02:06:37.812633Z","pmid":"39406032","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":[]}