Regulates Wnt proteins sorting and secretion in a feedback regulatory mechanism. This reciprocal interaction plays a key role in the regulation of expression, subcellular location, binding and organelle-specific association of Wnt proteins. Also plays an important role in establishment of the anterior-posterior body axis formation during development (By similarity). Interacts with WNT3A. Interacts with WNT1, WNT3 and WNT5A. Expressed in the brain, skeletal muscle, heart muscle, lung, gut, liver, and kidney (at protein level) (PubMed:20652957). In the brain, expressed in the cortex, striatum, ventral tegmentum, nucleus accumbens and to a lesser extent in the Purkinjie cells in the cerebellum (PubMed:20652957). Expressed in eye iridocorneal angle (PubMed:15326124). N-glycosylated. Belongs to the wntless family.