Classical studies showed that retinoids were involved in many developmental processes.
Retinoid acid receptors belong to one of the most complex subfamilies of the nuclear
hormone receptor superfamily as both RAR and RXR receptors are encoded by a number of
related genes each of which generates distinct isoforms. These isoforms are highly
conserved between species and show complex stage and tissue specific patterns of
expression, thus suggesting a molecular basis for the multiple effects of retinoids. However …