Denervation impairs regeneration of amputated zebrafish fins

info:eu-repo/grantAgreement/FCT/3599-PPCDT/126111/PT We thank to the IMM Fish Facility manager Lara Carvalho for support with fish care, to the CEDOC Fish Facility, to the IMM Bioimaging Unit and to the IGC Unit of Imaging and Cytometry. We thank to Leonor Saude, Henry Roehl and Kenneth Poss for providing probes. We thank Jeremy Brockes, Jacqueline Geraudie, Rita Fior, Elsa Abranches, Joaquin Rodriguez Leon, Nuno Afonso, Rita Mateus and Pedro Alves for reading the manuscript and for insightful discussions that lead to this work. Mariana Guedes Simoes was supported by a PhD grant from Fundacao para a Ciencia e Tecnologia (FCT), Portugal. Anabela Bensimon-Brito was suported by the ERC Reseal project (2007-StG-208631). The research presented in this manuscript has been funded by FCT research grants (PTDC/SAU-GMG/101537/2008 PTDC/SAU-OBD/100200/2008 PTDC/BEX-BID/1176/2012).Background: Zebrafish are able to regenerate many of its tissues and organs after damage. In amphibians this process is regulated by nerve fibres present at the site of injury, which have been proposed to release factors into the amputated limbs/fins, promoting and sustaining the proliferation of blastemal cells. Although some candidate factors have been proposed to mediate the nerve dependency of regeneration, the molecular mechanisms involved in this process remain unclear. Results: We have used zebrafish as a model system to address the role of nerve fibres in fin regeneration. We have developed a protocol for pectoral fin denervation followed by amputation and analysed the regenerative process under this experimental conditions. Upon denervation fins were able to close the wound and form a wound epidermis, but could not establish a functional apical epithelial cap, with a posterior failure of blastema formation and outgrowth, and the accumulation of several defects. The expression patterns of genes known to be key players during fin regeneration were altered upon denervation, suggesting that nerves can contribute to the regulation of the Fgf, Wnt and Shh pathways during zebrafish fin regeneration. Conclusions: Our results demonstrate that proper innervation of the zebrafish pectoral fin is essential for a successful regenerative process, and establish this organism as a useful model to understand the molecular and cellular mechanisms of nerve dependence, during vertebrate regeneration.publishersversionpublishe