The aim of the project is to implement one international mobility submitted to the call HORIZON-MSCA-2022-PF-01 with the Seal of Excellence evaluation, but due to the limited budget of the call not funded by Horizon Europe. The project will contribute to the internationalization and improvement of the quality of research in the Czech Republic and the professional growth of researchers. The scientific project will study the mechanism of retinoic acid and its role during the development of vertebrates. These findings will be useful for potential therapeutic interventions.