Fig. 7

sf-1 homozygous mutant zebrafish lost their gonads. A Generation of sf-1^−/− zebrafish via CRISPR/Cas9 technology. a. The target gene for knockout was located within exon 3. Exons are denoted by blue boxes, while introns are represented by folded lines. The white squares indicate untranslated regions. b and c. In comparison to the wild type, the mutant exhibits an insertion of 13 bases, resulting in premature termination of translation at the 59th amino acid. B Histological identification of the first and second sexual characteristics in wild-type and sf-1 mutant zebrafish. The body (a–e), pelvic fin (f–j), caudal fin (k–o), anal fin (p–t), genital papilla (u–y), and gonad at the cloaca (I–IV) were observed (n = 10). C HE staining of the gonads in wild-type and sf-1 heterozygous mutant zebrafish. sg, spermatogonia; sc, spermatocyte; sp, sperm cell. I–IV refers to oocytes of various stages