Caspase-dependent cleavage of nucleic acids

Autoimmune diseases are frequently characterized by the presence of autoant ibodies directed against nucleic acid-protein complexes present in the nucl eus of the cell. The mechanisms by which these autoantigenic molecules esca pe immunological tolerance are largely unknown, although a number of recent observations suggest that modified self-proteins generated during apoptosi s may play an important role in the development of autoimmunity. It has bee n hypothesized that the recognition of these modified self-proteins by the immune system may promote autoantibody production, While apoptosis is speci fically characterized by posttranslational modification of proteins, recent findings also show that nucleic acids are modified, This review summarizes the specific cleavages of some of these key nucleic acids, i.e. chromosoma l DNA, ribosomal RNA and small structural RNAs (U1 snRNA, Y RNA), in apopto tic cells.