Predicted to enable calcium ion binding activity. Acts upstream of with a positive effect on retrograde trans-synaptic signaling. Is active in postsynaptic cytosol. Is expressed in several structures, including adult heart; anterior endoderm; anterior endoderm anlage; embryonic dorsal epidermis; and embryonic/larval midgut primordium. Orthologous to human PEF1 (penta-EF-hand domain containing 1).