Enables phosphatidylinositol-3,4-bisphosphate binding activity and phospholipid binding activity. Acts upstream of or within adaptation of rhodopsin mediated signaling and retina layer formation. Located in extracellular region; neuron to neuron synapse; and photoreceptor inner segment. Is extrinsic component of plasma membrane. Used to study X-linked juvenile retinoschisis 1. Human ortholog(s) of this gene implicated in X-linked juvenile retinoschisis 1 and retinoschisis. Orthologous to human RS1 (retinoschisin 1). [provided by Alliance of Genome Resources, Apr 2022]