%0 Journal Article
%T GLI3 repressor but not GLI3 activator is essential for mouse eye patterning and morphogenesis.
%A Wiegering A
%A Petzsch P
%A Köhrer K
%A Rüther U
%A Gerhardt C
%J Dev Biol
%V 450
%N 2
%D 06 2019 15
%M 30953627
%F 3.148
%R 10.1016/j.ydbio.2019.02.018
%X Since 1967, it is known that the loss of GLI3 causes very severe defects in murine eye development. GLI3 is able to act as a transcriptional activator (GLI3-A) or as a transcriptional repressor (GLI3-R). Soon after the discovery of these GLI3 isoforms, the question arose which of the different isoforms is involved in eye formation - GLI3-A, GLI3-R or even both. For several years, this question remained elusive. By analysing the eye morphogenesis of Gli3XtJ/XtJ mouse embryos that lack GLI3-A and GLI3-R and of Gli3Δ699/Δ699 mouse embryos in which only GLI3-A is missing, we revealed that GLI3-A is dispensable in vertebrate eye formation. Remarkably, our study shows that GLI3-R is sufficient for the creation of morphologically normal eyes although the molecular setup deviates substantially from normality. In depth-investigations elucidated that GLI3-R controls numerous key players in eye development and governs lens and retina development at least partially via regulating WNT/β-CATENIN signalling.