J. Geraudie et P. Ferretti, CORRELATION BETWEEN RA-INDUCED APOPTOSIS AND PATTERNING DEFECTS IN REGENERATING FINS AND LIMBS, The International journal of developmental biology, 41(3), 1997, pp. 529-532
We have compared the ability of RA to induce apoptosis in regenerating
fins and limbs in order to establish whether there may be a possible
causal relationship between RA-induced cell death and the different pa
tterning abnormalities observed in these two systems following RA trea
tment. In regenerating fins RA affects the anteroposterior axis and in
duces narrowing of the fin and fusion of rays. In regenerating limbs h
owever, it mainly affects the proximodistal axis, where dose-dependent
duplications of segments are observed. We report here that RA increas
es cell death by apoptosis both in fin and limb regenerates independen
tly from the route of administration, but in distinct cell populations
. In regenerating fins, RA-induced apoptosis is observed only in the w
ound epidermis, whereas in regenerating limbs significant apoptosis is
observed mainly in the blastema mesenchyme. Altogether, these finding
s support the view that RA-induced apoptosis is causally related to th
e patterning defects observed in fins and limbs.