{"doi":"10.1073/pnas.2002082117","title":"Redundant and additive functions of the four Lef/Tcf transcription factors in lung epithelial progenitors","abstract":"In multicellular organisms, paralogs from gene duplication survive purifying selection by evolving tissue-specific expression and function. Whether this genetic redundancy is also selected for within a single cell type is unclear for multimember paralogs, as exemplified by the four obligatory Lef/Tcf transcription factors of canonical Wnt signaling, mainly due to the complex genetics involved. Using the developing mouse lung as a model system, we generate two quadruple conditional knockouts, four triple mutants, and various combinations of double mutants, showing that the four Lef/Tcf genes function redundantly in the presence of at least two Lef/Tcf paralogs, but additively upon losing additional paralogs to specify and maintain lung epithelial progenitors. Prelung-specification, pan-epithelial double knockouts have no lung phenotype; triple knockouts have varying phenotypes, including defective branching and tracheoesophageal fistulas; and the quadruple knockout barely forms a lung, resembling the Ctnnb1 mutant. Postlung-specification deletion of all four Lef/Tcf genes leads to branching defects, down-regulation of progenitor genes, premature alveolar differentiation, and derepression of gastrointestinal genes, again phenocopying the corresponding Ctnnb1 mutant. Our study supports a monotonic, positive signaling relationship between CTNNB1 and Lef/Tcf in lung epithelial progenitors as opposed to reported repressor functions of Lef/Tcf, and represents a thorough in vivo analysis of cell-type-specific genetic redundancy among the four Lef/Tcf paralogs.","journal":"Proceedings of the National Academy of Sciences","year":2020,"id":99175,"datarank":0.515098080672772,"base_score":3.4339872044851463,"endowment":3.4339872044851463,"self_citation_contribution":0.515098080672772,"citation_network_contribution":0.0,"self_endowment_contribution":0.515098080672772,"citer_contribution":0.0,"corpus_percentile":null,"corpus_rank":null,"citation_count":30,"citer_count":0,"citers_with_citation_signal":0,"citers_with_endowment":0,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":0.9452,"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":382728,"name":"Haruhiko Akiyama","orcid":"0000-0002-5661-9895","position":1,"is_corresponding":false},{"id":239541,"name":"Jichao Chen","orcid":"0000-0003-2749-8550","position":2,"is_corresponding":false},{"id":488473,"name":"Kamryn N. Gerner-Mauro","orcid":"0000-0003-1690-4234","position":0,"is_corresponding":true}],"reference_count":45,"raw_metadata":{"citation_network_status":"fetched"},"created_at":"2026-07-18T22:37:35.547042Z","pmid":"32414917","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":[]}