Transgenic mice with neuronal overexpression of BCL-2 gene present navigation disabilites in a water task

In the CNS, Bcl-2 is an antiapoptotic gene involved in the regulation of ne uronal death. Transgenic mice overexpressing the human gene Bcl-2 (Hu-bcl-2 mice) showed delayed acquisition in two tasks requiring them to find a hid den platform starting from either a random or a constant starting location. The same mice were not deficient in another task requiring them to find a visible platform suggesting that the delay observed was not due to motor, v isual or motivational deficits in the water. The delay observed in Hu-bcl-2 mice was more important in the random starting test in which the allocentr ic demand for navigation was stronger. The results suggested that allocentr ic navigation is particularly sensitive to abnormal CNS maturation followin g the overexpression of the bcl-2 gene. The specific deficits (motor learning, fear-related behavior and allocentri c navigation) observed in Hu-bcl-2 mice suggest that the regulation of deve lopmental neuronal death is crucial for multisensorial learning and emotion al behavior. (C) 2001 IBRO. Published by Elsevier Science Ltd. All rights r eserved.