Fig. 1

Generation, Cre-LoxP recombination efficiency and electroretinography (ERG) of inducible Gnat2^CreERT2 mice. A Knock-in (KI) of a CreER^T2 sequence to the translational start codon “ATG” in exon 2 of the Gnat2 gene in mouse embryonic stem (ES) cells; confirmation of germline transmissions by crossing the male chimera with female ACTB-FLPe mice to remove the neomycin cassette. (B and C) Immunohistochemistry (IHC) of the retinal sections and whole mounts from 2-month-old Gnat2^CreERT2/+Ai14D^+/- mice with an antibody against ARR3 (green). Around 10 to 15% of Arr3-positive cone cells (green) expressed td-Tomato (red) after tamoxifen induction. (D and E) Scotopic serial intensity ERG showed no significant difference in a- or b- wave amplitudes between C57BL/6 J (wild-type, WT), Gnat2^CreERT2/+, and Gnat2^CreERT2 mice at 2 months-old; photopic serial intensity ERG showed no significant difference between WT, Gnat2^CreERT2/+ mice, however, there were extinguished responses in Gnat2^CreERT2 mice, which indicated a loss of cone function in homozygous Gnat2^CreERT2 mouse