Apoptosis and its functional significance in molluscs.

Programmed cell death leading to apoptosis is essential for normal development and homeostasis in plants and throughout the animal kingdom. Although there are differences in apoptotic mechanisms between lower animals and vertebrates, crucial biochemical components of the programmed cell death pathways remained remarkably conserved throughout evolution. Despite decades of studies on the neurobiology and development of mollusks, comparatively little is known about the mechanisms of apoptosis in this phylum. In this review, an attempt is made to summarize data obtained on mollusks so far, and to discuss the molecular mechanisms, the functional and ecological significance of apoptosis and the advantages of snail preparations as tools for programmed cell death research. A definitive comparison of the data obtained on mollusks with those obtained on the more widely studied vertebrates, will contribute to the better understanding of the apoptotic process in general and of its evolutionary development.