Scientists have engineered a new mouse model that reveals how Opn3–a little-known blue light-sensitive protein–affects body temperature and eye development. By inserting a phiC31 integrase sequence into the Opn3 gene using CRISPR-Cas9, the team created a dual-purpose system that both silences the gene and labels its active cells with fluorescent light. The modified mice exhibited a sharp drop in body temperature during cold exposure and developed myopia-like eye features, confirming Opn3’s vital physiological roles.
