deltaNp63 is required in the early development of Xenopus laevis epidermis

M. GUADALUPE BARRIONUEVO; CELESTE TRÍBULO; MANUEL J. AYBAR

Tafí del Valle, Tucumán

Jornada; XXVII Jornadas de la Asociación de Biología de Tucumán; 2010

Asociación de Biología de Tucumán

The p63 gene is a transcription factor member of the p53 gene family. In mammals, this gene has two promoters that generate two types of protein isoforms, TAp63 and DNp63. In Xenopus laevis it was identified only the DNp63g isoform, whose role in the development of this amphibian remains unknown. In mammals and zebrafish, DNp63 is needed in the development of the epidermis. Previously, we determined that DNp63 is expressed in the prospective epidermis of Xenopus laevis embryo. We proceeded to analyze the role of DNp63 in the specification of the epidermis. First, we carried out DNp63 gain of function experiments in ectoderm explants. It was observed an increase of the epidermal markers and a decreased of the neural markers analyzed by RT-PCR. Then, we built a chimeric fluorescent protein (dnDNp63GFP) that acts as a dominant negative of DNp63. We carried out loss of function experiments overexpressing dnDNp63GFP and a Morpholino antisense oligonucleotide. The DNp63 inhibition leaded to a lower expression of epidermal marker genes (XK81a, rexp52) and an increase in the expression of neural markers (Slug, FoxD3, Sox2). The same results were obtained when the expression of these marker genes was analyzed in ectoderm explants. These results suggest that the DNp63 gene is involved in the induction of the epidermis and is required for the proper development of this tissue.