AIM: To investigate the mutually inductive interactions that occur between the lens and retinal tissue during the development of the vertebrate eye. METHODS: Cre-positive mice were mated with Cre-negative mice to generate 50% Cre-positive (conditional knockout, CKO) and 50% Cre-negative offspring (wild type, WT). The embryos were fixed in 4% paraformaldehyde, embedded in paraffin, and sectioned to a thickness of 4μm. The sections were processed for hematoxylin and eosin staining. The primary antibody used for immunofluorescence detection was sc-9305 bone morphogenetic proteins (bmp7) (Santa Cruz, US). The secondary antibody was IF-0314 aG0IgG/FITC (Santa Cruz) in combination with the primary antibody. Bright-field and fluorescent images were taken. RESULTS: Changes in the lens and retina were associated with specific alterations to the expression of type IA BMP receptor [BMPR-IA (ALK3)], which have already been implicated in eye growth. BMPR-IA was required for lens and retinal growth, but was not essential for the formation of lens. We observed that the expression of Bmp7 in the embryonic retina was reduced in the ALK3 lens of CKO mice. This phenomenon became increasingly visible in accordance with embryo development. This apparent alteration was present at stage E15.5. CONCLUSION: ALK3 is essential for lens and retinal growth. Mutually inductive interactions between the lens and retina are present in the developing mouse eye.