Wnt and Hedgehog: Secretion of Lipid-Modified Morphogens

The membrane-anchored morphogens Hedgehog (Hh) and Wingless (Wg) play major roles in tissue patterning, tissue maintenance, and disease progression. Hh and Wg must be secreted for their paracrine signaling function. In addition to being secreted on exovesicles, Hh and Wg are found on circulating lipoproteins and decorating cytonemes as well as in soluble forms. The mechanism of Hh exovesicle generation involves its endocytosis from the cell...