Astyanax transgenesis and husbandry: how cavefish enters the laboratory.

Astyanax mexicanus, a teleost fish comprising both sighted river-dwelling and blind cave-dwelling morphs, is becoming increasingly used in the field of developmental and evolutionary biology. Thus, new experimental and technological tools are needed on this emerging fish model by the expanding scientific community. Here, we describe Astyanax husbandry and egg spawning habits, a prerequisite to the successful establishment of Astyanax transgenic lines. We then compare two different transgenesis methods on both surface and cave Astyanax. Both meganuclease (I-SceI)- and transposase (Tol2)-mediated transgenesis are equivalently efficient, resulting in ∼40% mosaic transgenic fish in F0. Furthermore, the transmission rate was analyzed in F1 in the case of the I-SceI method and was found to be 16%. Finally, the transgene was found stable up the F3 generation, demonstrating the feasibility of generating stable transgenic lines in Astyanax and opening a wide range of possibilities for this fish model.