Using the Frog Epidermis to Uncover Desmosome Function and Regulation in the Developing Embryo

This dissertation explored the function and regulation of desmosomes using the frog model, Xenopus laevis, focusing on the desmosomal protein desmoplakin (Dsp) in embryonic epidermal development. It was found that desmosomes were present from early developmental stages and increased in number as the embryo developed. Deficiency in Dsp led to defects in epidermal structures and the heart, similar to mammalian models, and increased susceptibility to epidermal damage under mechanical stress. The study also suggested a role for desmosomes in radial intercalation, with reduced Dsp affecting intercalating cell types. Additionally, the c-Jun N-terminal kinase (JNK) pathway might regulate desmosome assembly, as JNK inhibition partially restored mechanical integrity in Dsp-deficient embryos.