Target identification and validation is gaining relevance in early phases of Drug Discovery. This process allows characterizing the role of a protein or pathway of interest and provides selection arguments to define the required properties of the compounds to be screened. So far, many in silico and in vitro techniques have failed due to the pharmacological promiscuity of the compounds as well as the lack of complete information about protein interaction and compensation.
Zebrafish shows a great potential to be used in early stages of discovery, thanks to its properties that include transparency, easiness to treat with compounds, high conservation with other vertebrates, cost-effectiveness and possibility to generate transgenic lines targeting specific organs and pathways. Zebrafish has also been proposed as a good model to validate a target function due to its capacity to assess a specific process combined with a general toxicity assessment of drug screening.