Interacts with clathrin light chain A and stimulates clathrin self-assembly and clathrin-mediated endocytosis. Interacts with CLTA. Most abundant in brain. Also expressed in testis and ovary and, at much lower levels, in kidney and heart. Mice display impaired clathrin assembly and clathrin-mediated endocytosis. Transgenic mice with up-regulated forebrain expression of Caly display a range of abnormal behaviors including spontaneous hyperactivity, reduced anxiety and/or impaired harm avoidance. Belongs to the NSG family. The human ortholog was originally thought to interact with the D1 dopamine receptor (DRD1) and to play a role in potentiating calcium ion-dependent signaling but this work was later retracted.