Promotes lrp6 phosphorylation by casein kinases and thereby plays a role in Wnt signaling. May be a membrane scaffold protein involved in the self-aggregation of lrp6 further enhancing its activity. Required for neural crest formation. Interacts with lrp6. Interacts with casein kinases. Largely located to vesicle-like structures. Expression widely distributed both maternally and zygotically. During gastrulation, strong expression in the posterior end near the blastopore. Morphants have defects in neural crest formation. At the tadpole stage, animals are often less pigmented with ventrally bent tails. Embryos develop smaller eyes and forebrain structures. Belongs to the TMEM198 family.