title: Systematic discovery of novel ciliary genes through functional genomics in the zebrafish.
abstract: Cilia are microtubule-based hair-like organelles that play many important roles in development and physiology, and are implicated in a rapidly expanding spectrum of human diseases, collectively termed ciliopathies. Primary ciliary dyskinesia (PCD), one of the most prevalent of ciliopathies, arises from abnormalities in the differentiation or motility of the motile cilia. Despite their biomedical importance, a methodical functional screen for ciliary genes has not been carried out in any vertebrate at the organismal level. We sought to systematically discover novel motile cilia genes by identifying the genes induced by Foxj1, a winged-helix transcription factor that has an evolutionarily conserved role as the master regulator of motile cilia biogenesis. Unexpectedly, we find that the majority of the Foxj1-induced genes have not been associated with cilia before. To characterize these novel putative ciliary genes, we subjected 50 randomly selected candidates to a systematic functional phenotypic screen in zebrafish embryos. Remarkably, we find that over 60% are required for ciliary differentiation or function, whereas 30% of the proteins encoded by these genes localize to motile cilia. We also show that these genes regulate the proper differentiation and beating of motile cilia. This collection of Foxj1-induced genes will be invaluable for furthering our understanding of ciliary biology, and in the identification of new mutations underlying ciliary disorders in humans.
authors.affiliation: Institute of Molecular and Cell Biology, 61 Biopolis Drive, Singapore 138673 semilc@imcb.a-star.edu.sg sudipto@imcb.a-star.edu.sg.
authors.forename: Semil P
authors.initials: SP
authors.lastname: Choksi
authors.affiliation: Institute of Molecular and Cell Biology, 61 Biopolis Drive, Singapore 138673 NUS Graduate School of Integrative Sciences and Engineering, Centre for Life Sciences, 28 Medical Drive, Singapore 117456.
authors.forename: Deepak
authors.initials: D
authors.lastname: Babu
authors.affiliation: Institute of Molecular and Cell Biology, 61 Biopolis Drive, Singapore 138673.
authors.forename: Doreen
authors.initials: D
authors.lastname: Lau
authors.affiliation: Institute of Molecular and Cell Biology, 61 Biopolis Drive, Singapore 138673.
authors.forename: Xianwen
authors.initials: X
authors.lastname: Yu
authors.affiliation: Institute of Molecular and Cell Biology, 61 Biopolis Drive, Singapore 138673 NUS Graduate School of Integrative Sciences and Engineering, Centre for Life Sciences, 28 Medical Drive, Singapore 117456 Department of Biological Sciences, National University of Singapore, 14 Science Drive 4, Singapore 117543 Department of Paediatrics, Yong Loo Lin School of Medicine, National University of Singapore, 1E Kent Ridge Road, Singapore 119288 semilc@imcb.a-star.edu.sg sudipto@imcb.a-star.edu.sg.
authors.forename: Sudipto
authors.initials: S
authors.lastname: Roy
mesh_terms: D000818:Animals; D002923:Cilia / Q000187:drug effects / Q000235:genetics*; D002925:Ciliary Motility Disorders / Q000235:genetics; D004625:Embryo, Nonmammalian / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D051858:Forkhead Transcription Factors / Q000235:genetics / Q000378:metabolism; D018507:Gene Expression Regulation, Developmental / Q000187:drug effects; D055785:Gene Knockdown Techniques; D056726:Genetic Association Studies; D023281:Genomics; D049452:Green Fluorescent Proteins / Q000378:metabolism; D006801:Humans; D060172:Morpholinos / Q000494:pharmacology; D038081:Organogenesis / Q000187:drug effects / Q000235:genetics; D010641:Phenotype; D015854:Up-Regulation / Q000187:drug effects / Q000235:genetics; D015027:Zebrafish / Q000196:embryology / Q000235:genetics*; D029961:Zebrafish Proteins / Q000235:genetics / Q000378:metabolism
chemical_list: D051858:Forkhead Transcription Factors; C533681:Foxj1a protein, zebrafish; D060172:Morpholinos; D029961:Zebrafish Proteins; D049452:Green Fluorescent Proteins
keywords: Ciliary gene screen; Ciliopathy; Foxj1; Motile cilia; Primary ciliary dyskinesia; Zebrafish