Predicted to enable calcium ion binding activity; identical protein binding activity; and phospholipid binding activity. Predicted to be involved in endoplasmic reticulum-plasma membrane tethering and lipid transport. Predicted to be located in endoplasmic reticulum. Predicted to be integral component of endoplasmic reticulum membrane. Predicted to be extrinsic component of cytoplasmic side of plasma membrane and intrinsic component of endoplasmic reticulum membrane. Is expressed in several structures, including foregut; genitourinary system; nervous system; sensory organ; and spleen. Orthologous to human ESYT1 (extended synaptotagmin 1). [provided by Alliance of Genome Resources, Apr 2022]