0000000000611118
AUTHOR
Maria Rosa Padros
Natural and induced apoptosis during lymphocyte development in the axolotl
Lymphocytes apoptosis was characterized in a urodele amphibian, the axolotl, by morphology using electron microscopy and by flow cytometry after propidium iodide staining, as well as by biochemical criteria with the detection of DNA ladders after glucocorticoid treatment. The morphological and biochemical features observed in treated axolotls are in accordance with the criteria of apoptosis found in different models of mammalian lymphocyte programmed cell death. The onset of natural apoptosis was then detected by DNA fragmentation in thymus and in spleen during lymphocyte development and ontogenesis. A typical DNA ladder characteristic of apoptosis is detectable in the thymus as early as 5 …
Axolotl MHC class II β chain: predominance of one allele and alternative splicing of the β1 domain
The axolotl MHC is composed of multiple polymorphic class I loci linked to class II B loci. In this report, evidence of the existence of one class II B locus (Amme-DAB) that codes for two different transcripts is given. A 2.1-kb transcript is translated to a complete β chain and a shorter transcript of 1.8 kb encodes a molecule lacking the β1 domain. For two complete class II B mRNA synthesized, up to one mRNA devoid of the β1 domain is synthesized. Alternative splicing involving a peptide binding domain at a class II B locus evidenced in axolotl (Ambystoma mexicanum) is also observed for A. trigrinum, the tiger salamander. Very little variability is found among various axolotl MHC class II…