FIGURE 1.
Wnt secretion. Wnt proteins are translated into the endoplasmic reticulum where they are acylated by Porcupine (PORCN). Wntless (Wls/Evi) escorts acylated Wnt to the cell surface where it may associate with the plasma membrane (PM-associated Wnt) or with proteoglycans (PG-associated Wnt). Carrier proteins, such as SWIM and AFM, facilitate solubility of cell free Wnt proteins. Wnt proteins can signal at greater distances via cell projections (also known as filopodia, cytonemes, and nanotubes) or by associating with exosomes or liposomes