congresos y reuniones científicas
A balance between the anti-apoptotic activity of slug and the apoptotic activity of msx1 is required for the proper development of the neural crest
CELESTE TRÍBULO; MANUEL J. AYBAR; SARA S. SÁNCHEZ; ROBERTO MAYOR
University of Calgary, Calgary, Alberta, Canada.
Congreso; Society for Developmental Biology, 63rd annual meeting; 2004
Society for Developmental Biology
Apoptosis is an important cellular process in all animals and is used during development to sculpt tissues and organs. It has been shown that apoptosis plays an important role in neural crest patterning. Our previous results in Xenopus confirmed that apoptosis is localized within the neural crest and that during neural crest development BMP4 and msx1 promote apoptosis while Slug acts as an anti-apoptotic gene. In the present work, we compared the patterns of TUNEL staining with the expression of msx1 and Slug, both expressed in the neural folds. We show that in the neural fold region where Slug is expressed, cells undergo less apoptosis than those cells in the region where msx1 is expressed. To analyze whether apoptosis in the neural crest was activated by a cell autonomous program, we performed grafting experiments. Our results suggest that signals in the cephalic neural crest are sufficient to maintain a high level of apoptosis. Finally, we analyzed whether Slug and msx1 were able to modify neural crest derivatives. We found that overexpression of Slug or msx1 affects the size of neural crest cartilage derivatives in a similar way to the effects produced when Bcl2 or Bax was experimentally modified. We suggest that the balance of anti-apoptotic and apoptotic factors serves to correctly define the number of neural crest cells and to control the correct size of its derivatives.