CRISPR indusert knockout i laks

A novel paralog of the thyroid-stimulating hormone (tshbb) has recently been discovered. It has become evident that this paralog may hold the key to understanding smoltification. In addition, smoltification and sexual maturation in salmon is two combatable events. The initiation of maturation starts with an elevation in follicular stimulating hormone (fsh) through increased activity in the Hypothalamic-Pituitary-Gonadal axis. This project is designed to elucidate the function of tshbb and fsh, and investigate how environmental ques like photoperiod controls whether salmon smoltify or matures. The project aims to generate novel knowledge that will allow a more robust smolt production and eliminate early maturation through efficient activation of the Hypothalamic-Pituitary-Thyroid axis and reduce or inhibit the initiation of maturation using photo-manipulation. To investigate a potential interaction between smoltification and early maturation we will generate several salmon knockouts produced (tshba, tshbb and fshb knock out salmon) using the novel genome-editing tool CRISPR/Cas9. This will allow us to better understand how the thyroid and gonadotropic axis function and regulate smoltification and maturation, respectively. Both sexes of Atlantic salmon will be used for this experiment. The experiment will also improve our understanding of how the aquaculture industry can facilitate the production of robust salmon. We will use 200 fish in each knockout (totally 1000 fish), subjected to different photomanipulations to induce smoltification and/or maturation. Throughout the study we will continuously monitor the welfare of the fish. We have already conducted a pilot study to reduce the number of salmon. Planning, conducting and reviewing research protocols has been implemented to maximize welfare and minimize pain and distress on the experimental animals. Physiological investigations of brain, pituitary, gill, blood, kidney, heart, and liver will be conducted after the fish has been killed. The fish is first anesthetized using FINQUEL
(tricaine) followed by decapitation.