The present invention describes a calcium-binding myristoylated protein with homology to calcineurin B which interacts preferentially with presenilin 2 protein. Also, the present invention relates to methods that alter protein-protein interaction of the calcium-binding myristoylated protein with presenilin 2 thereby reducing deleterious effects of the protein-protein interaction, such as apoptosis. The present invention further relates to introducing and expressing a mutant presenilin 2 protein or mutant calcium-binding myristoylated protein to modulate cell functions relating to calcium signaling and apoptosis.