Excess Dally-like Induces Malformation of Legs.

Glypicans are closely associated with organ development and tumorigenesis in animals. Dally-like (Dlp), a membrane-bound glypican, plays pivotal roles in various biological processes in . In this study, we observed that an excess of Dlp led to the malformation of legs, particularly affecting the distal part. Accordingly, the leg disc was shrunken and frequently exhibited aberrant morphology. In addition, elevated Dlp levels induced ectopic cell death with no apparent cell proliferation changes. Furthermore, Dlp overexpression in the posterior compartment significantly altered Wingless (Wg) distribution. We observed a marked expansion of Wg distribution within the posterior compartment, accompanied by a corresponding decrease in the anterior compartment. It appears that excess Dlp guides Wg to diffuse to cells with higher Dlp levels. In addition, the () gene, which is crucial for leg patterning, was up-regulated significantly. Notably, () and () expression, also essential for leg patterning and development, only appeared to be negligibly affected. Based on these findings, we speculate that excess Dlp may contribute to malformations of the distal leg region of , possibly through its influence on Wg distribution, expression and induced cell death. Our research advances the understanding of Dlp function in leg development.