• Background: Retinaldehyde binding protein 1 (RLBP1) is a key molecule responsible for transporting 11-cis-retinal in the visual cycle. Mutations in RLBP1 can cause abnormal visual cycle and lead to degeneration of photoreceptor cells and retinal pigment epithelium (RPE) cells. RLBP1 is highly expressed in ocular tissues, particularly in Müller cells and RPE cells.
• Gene editing strategy: An icre/ERT2-tdtomato sequence cassette was placed in the mouse Rlbp1 gene under the control of the Rlbp1 promoter in B-Rlbp1-iCreERT2-tdtomato mice.
• Validation: TdTomato expression was observed exclusively in the eye, confirming tissue-specific expression driven by the Rlbp1 promoter in B-Rlbp1-iCreERT2-tdtomato mice.
• Tamoxifen-induced ablation led to structural disruption across the retinal layers, cells in the GCL, INL, and ONL appeared disordered in B-EGFP-DTA, Rlbp1-iCreERT2-tdTomato mice.
• Application: As the predominant radial glial cells in the retina, Müller cell clearance or ablation models serve as a core experimental approach for investigating retinal degeneration, vascular homeostasis, and neural regeneration.

Gene targeting strategy for B-EGFP-DTA, Rlbp1-iCreERT2-tdTomato mice.

An icre/ERT2-tdtomato sequence cassette was placed in the mouse Rlbp1 gene under the control of the Rlbp1 promoter in B-Rlbp1-iCreERT2-tdtomato mice.

B-ROSA26-EGFP-DTA mice have STOP cassettes preventing expression of diphtheria toxin fragment A (DTA). DTA expression will be activated, if STOP cassettes are removed, resulting in the specific ablation of the cre-expressing cells. ROSA26-EGFP-DTA mice are useful for Cre-inducible deletion of specific groups of cells.

B-EGFP-DTA, Rlbp1-iCreERT2-tdTomato mice were obtained by crossing B-Rlbp1-iCreERT2-tdtomato mice (113974) and B-ROSA26-EGFP-DTA mice (110156).

TdTomato Expression in B-Rlbp1-iCreERT2-tdtomato mice. TdTomato expression was observed exclusively in the eye, confirming tissue-specific expression driven by the Rlbp1 promoter in B-Rlbp1-iCreERT2-tdtomato mice. Scale, 40x.

Tamoxifen-Induced retinal degeneration in B-EGFP-DTA, Rlbp1-iCreERT2-tdTomato mice.

B-EGFP-DTA, Rlbp1-iCreERT2-tdTomato mice (female, 6-week-old) were divided into two groups. G1 (n=2) received daily intraperitoneal (i.p.) vehicle injections for 5 days. G2 (n=3) received i.p. tamoxifen (1 mg/mouse) daily for 5 days. After a 7-day washout period, tissues were collected for and analyzed with H&E staining. The results showed that tamoxifen-induced ablation led to structural disruption across the retinal layers, cells in the GCL, INL, and ONL appeared disordered in B-EGFP-DTA, Rlbp1-iCreERT2-tdTomato mice. Scale, 200x.