Rodríguez Arrizabalaga, MariñaHernández Núñez, IsmaelCandal Suárez, Eva MaríaBarreiro Iglesias, Antón2022-12-292022-12-292023Experimental Eye Research 226 (2023). https://doi.org/10.1016/j.exer.2022.109333http://hdl.handle.net/10347/29667Work in the catshark Scyliorhinus canicula has shown that the evolutionary origin of postnatal neurogenesis in vertebrates is earlier than previously thought. Thus, the catshark can serve as a model of interest to understand postnatal neurogenic processes and their evolution in vertebrates. One of the best characterized neurogenic niches of the catshark CNS is found in the peripheral region of the retina. Unfortunately, the lack of genetic tools in sharks limits the possibilities to deepen in the study of genes involved in the neurogenic process. Here, we report a method for gene knockdown in the juvenile catshark retina based on the use of Vivo-Morpholinos. To establish the method, we designed Vivo-Morpholinos against the proliferation marker PCNA. We first evaluated the possible toxicity of 3 different intraocular administration regimes. After this optimization step, we show that a single intraocular injection of the PCNA Vivo-Morpholino decreases the expression of PCNA in the peripheral retina, which leads to reduced mitotic activity in this region. This method will help in deciphering the role of other genes potentially involved in postnatal neurogenesis in this animal modeleng© 2022 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by- nc-nd/4.0/)Attribution-NonCommercial-NoDerivatives 4.0 Internacionalhttp://creativecommons.org/licenses/by-nc-nd/4.0/Cartilaginous fishRetinaVivo-morpholinoTUNELPCNApH3journal article10.1016/j.exer.2022.1093330014-4835open access