RT Journal Article SR Electronic T1 Atoh1 is required for the formation of lateral line electroreceptors and hair cells, whereas Foxg1 represses an electrosensory fate JF bioRxiv FD Cold Spring Harbor Laboratory SP 2023.04.15.537030 DO 10.1101/2023.04.15.537030 A1 Minařík, Martin A1 Campbell, Alexander S. A1 Franěk, Roman A1 Vazačová, Michaela A1 Havelka, Miloš A1 Gela, David A1 Pšenička, Martin A1 Baker, Clare V. H. YR 2024 UL http://biorxiv.org/content/early/2024/01/03/2023.04.15.537030.abstract AB In electroreceptive jawed fishes and amphibians, individual lateral line placodes form lines of neuromasts on the head containing mechanosensory hair cells, flanked by fields of ampullary organs containing electroreceptors - modified hair cells that respond to weak electric fields. Extensively shared gene expression between neuromasts and ampullary organs suggests that conserved molecular mechanisms are involved in their development, but a few transcription factor genes are restricted either to the developing electrosensory or mechanosensory lateral line. Here, we used CRISPR/Cas9-mediated mutagenesis in F0-injected sterlet embryos (Acipenser ruthenus, a sturgeon) to test the function of three such genes. We found that the ‘hair cell’ transcription factor gene Atoh1 is required for both hair cell and electroreceptor differentiation in sterlet, and for Pou4f3 and Gfi1 expression in both neuromasts and ampullary organs. These data support the conservation of developmental mechanisms between hair cells and electroreceptors. Targeting ampullary organ-restricted Neurod4 did not yield any phenotype, potentially owing to redundancy with other Neurod genes that we found to be expressed in sterlet ampullary organs. After targeting mechanosensory-restricted Foxg1, ampullary organs formed within neuromast lines, suggesting that Foxg1 normally represses their development. We speculate that electrosensory organs may be the ‘default’ fate of lateral line primordia in electroreceptive vertebrates.Competing Interest StatementThe authors have declared no competing interest.