Paulina Hanzelova, Connor Baird, Bidemi Keshinro, Reeham Kadhom, Robert L Lalonde, Marie-Andrée Akimenko
{"title":"An essential role for actinotrichia in zebrafish fin patterning and courtship behavior.","authors":"Paulina Hanzelova, Connor Baird, Bidemi Keshinro, Reeham Kadhom, Robert L Lalonde, Marie-Andrée Akimenko","doi":"10.1242/dev.204990","DOIUrl":null,"url":null,"abstract":"<p><p>A key difference between tetrapod limb buds and teleost fin buds is the presence of rigid actinotrichia fibers that guide the migrating cells contributing to ray formation. Major structural components of actinotrichia are encoded by fish-specific actinodin (And) genes, which were lost in tetrapods. To investigate the consequences of this loss during the fin-to-limb transition, we generated deletions in zebrafish and1 and and2 using CRISPR/Cas9 mutagenesis. Double mutants (and1-/-and2-/-) lack actinotrichia. Embryos and larvae have reduced fin fold size, with disorganized cell migration. In adults, all fin fold-derived skeletal structures are disrupted, including the rays of all fins, as well as the caudal fin endoskeleton. Surprisingly, double mutant males fail to breed, despite being fertile. Video analysis revealed that defects in the fins of males impair their ability to stimulate egg release. Our findings highlight the role of actinotrichia in both fin patterning and zebrafish courtship. We propose that actinodin gene maintenance is under strong selection in fish with similar courtship. We speculate that the loss of actinodin genes and a shift in courtship strategy may have coincided during tetrapod evolution.</p>","PeriodicalId":11375,"journal":{"name":"Development","volume":" ","pages":""},"PeriodicalIF":3.6000,"publicationDate":"2026-08-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13120675/pdf/","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Development","FirstCategoryId":"99","ListUrlMain":"https://doi.org/10.1242/dev.204990","RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"2026/4/14 0:00:00","PubModel":"Epub","JCR":"Q1","JCRName":"DEVELOPMENTAL BIOLOGY","Score":null,"Total":0}
引用次数: 0
Abstract
A key difference between tetrapod limb buds and teleost fin buds is the presence of rigid actinotrichia fibers that guide the migrating cells contributing to ray formation. Major structural components of actinotrichia are encoded by fish-specific actinodin (And) genes, which were lost in tetrapods. To investigate the consequences of this loss during the fin-to-limb transition, we generated deletions in zebrafish and1 and and2 using CRISPR/Cas9 mutagenesis. Double mutants (and1-/-and2-/-) lack actinotrichia. Embryos and larvae have reduced fin fold size, with disorganized cell migration. In adults, all fin fold-derived skeletal structures are disrupted, including the rays of all fins, as well as the caudal fin endoskeleton. Surprisingly, double mutant males fail to breed, despite being fertile. Video analysis revealed that defects in the fins of males impair their ability to stimulate egg release. Our findings highlight the role of actinotrichia in both fin patterning and zebrafish courtship. We propose that actinodin gene maintenance is under strong selection in fish with similar courtship. We speculate that the loss of actinodin genes and a shift in courtship strategy may have coincided during tetrapod evolution.
期刊介绍:
Development’s scope covers all aspects of plant and animal development, including stem cell biology and regeneration. The single most important criterion for acceptance in Development is scientific excellence. Research papers (articles and reports) should therefore pose and test a significant hypothesis or address a significant question, and should provide novel perspectives that advance our understanding of development. We also encourage submission of papers that use computational methods or mathematical models to obtain significant new insights into developmental biology topics. Manuscripts that are descriptive in nature will be considered only when they lay important groundwork for a field and/or provide novel resources for understanding developmental processes of broad interest to the community.
Development includes a Techniques and Resources section for the publication of new methods, datasets, and other types of resources. Papers describing new techniques should include a proof-of-principle demonstration that the technique is valuable to the developmental biology community; they need not include in-depth follow-up analysis. The technique must be described in sufficient detail to be easily replicated by other investigators. Development will also consider protocol-type papers of exceptional interest to the community. We welcome submission of Resource papers, for example those reporting new databases, systems-level datasets, or genetic resources of major value to the developmental biology community. For all papers, the data or resource described must be made available to the community with minimal restrictions upon publication.
To aid navigability, Development has dedicated sections of the journal to stem cells & regeneration and to human development. The criteria for acceptance into these sections is identical to those outlined above. Authors and editors are encouraged to nominate appropriate manuscripts for inclusion in one of these sections.