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English: Afther Wnt is synthesized, Wnt is acylated by the porcupine enzyme in the endoplasmic reticulum, resulting in the covalent bonding of palmitoleic acid to a conserved serine residue. It then travels through endosomes to the Golgi apparatus, where it binds to a carrier protein called Wntless, and subsequently, binds to lipoproteins in exosomes before being secreted into the cell's outer membrane.

Once secreted outside the cell, Wnt binds to frizzled receptors present in surrounding cells, particularly stem cells. Wnt binds to the frizzled receptor through palmitoleic acid and to the LRP co-stimulatory receptor on the other side, forming a triple complex. This Wnt-frizzled-LRP complex recruits the intracellular Dishevelled protein (DVL) to the intracellular domain of frizzled receptor and inactivates destruction complexes (Axin, GSK3, APC, CK1) which phoshorylates beta-catenin. Beta-catenin that has not undergone phosphorylation and ubiquitination enters the nucleus in a stable state and binds to the transcription factor TCF1, inducing the expression of genes involved in cell division and proliferation, such as c-Myc and CyclinD.

In the absence of Wnt, the frizzled receptor cannot form a complex with the LRP co-stimulatory receptor. Instead, the LRP receptor binds to inhibitory receptors DKK1 and Kremen to maintain an inactive state. At this time, the destruction complex is active and phosphorylates β-catenin. The phosphorylated β-catenin is multi-ubiquitinated by β-TrCP and degraded by the proteolytic complex proteasome. In the nucleus, TCF-1 acts as a transcriptional repressor along with the Groucho co-repressor to suppress gene expression.