Relationship: 1924



Wnt ligand stimulation leads to Frizzled activation

Upstream event


Wnt ligand stimulation

Downstream event


Frizzled activation

Key Event Relationship Overview


AOPs Referencing Relationship


Taxonomic Applicability


Term Scientific Term Evidence Link
Homo sapiens Homo sapiens High NCBI

Sex Applicability


Sex Evidence
Unspecific High

Life Stage Applicability


Term Evidence
All life stages Moderate

Key Event Relationship Description


Wnt ligand binds to Frizzled receptor (FZD), which leads to the Wnt signaling activation (Nile, Mukund, Stanger, Wang, & Hannoush, 2017).

Evidence Supporting this KER


Biological Plausibility


Upon the stimulation with Wnt ligand, Wnt ligand binds to FZD and form the complex with LRP5/6 (MacDonald et al., 2009).

Empirical Evidence


Dishevelled (DVL), a positive regulator of Wnt signaling, form the complex with FZD and lead to trigger the Wnt signaling together with Wnt coreceptor low-density lipoprotein (LDL) receptor-related protein 6 (LRP6) (Clevers & Nusse, 2012; X. Jiang et al., 2015).

Wnt binds to FZD and activate the Wnt signaling (Clevers & Nusse, 2012; Janda et al., 2012; Nile et al., 2017). Wnt binding towards FZD induce the formation of the protein complex with LRP5/6 and DVL, leading to the down-stream signaling activation (Clevers & Nusse, 2012).

Uncertainties and Inconsistencies


Some Wnt ligands bind to FZD, leading to Wnt/beta-catenin signaling inactivation. DVL, a positive regulator of Wnt signaling, has a controversial role to promote Wnt receptor degradation (X. Jiang et al., 2015). DVL-dependent regulation of FZD level is involved in mTORC1 signaling suppression via Wnt/beta-catenin signaling (H. Zeng et al., 2018).

Quantitative Understanding of the Linkage


Response-response Relationship


FZD5 can activate WNT3A/beta-catenin signaling in a dose-dependent manner (Hua et al., 2018). The increase in FZD5 protein enhances cell response to WNT3A. (Hua et al., 2018). LRP5 can augment WNT3A/beta-catenin signaling in a dose-dependent manner (Hua et al., 2018).



FZD7 enhances the activity of canonical Wnt/beta-catenin signaling with the treatment of WNT3A for 1 to 6 hrs (Cao et al., 2017).

Known modulating factors


The binding of Wnt and FZD induce the formation of the protein complex with the Dvl, Axin, CK1 GSK3, beta-catenin and APC to induce the beta-catenin translocation into the nucleus (Clevers & Nusse, 2012).

Known Feedforward/Feedback loops influencing this KER


The Wnt ligand is antagonized with secreted Frizzled-related proteins (sFRPs) and Wnt inhibitory protein (WIF), both of which can bind Wnts and inhibit interactions between WNT and FZD (Bovolenta, Esteve, Ruiz, Cisneros, & Lopez-Rios, 2008; Clevers & Nusse, 2012).

The Dickkopf 1 (DKK1) can disrupts Wnt-induced FZD-LRP6 complex formation (Clevers & Nusse, 2012; Ellwanger et al., 2008; Semenov, Zhang, & He, 2008).

Domain of Applicability


Wnt ligand stimulation leads to FZD activation in Homo sapiens (Clevers & Nusse, 2012).



Bovolenta, P., Esteve, P., Ruiz, J. M., Cisneros, E., & Lopez-Rios, J. (2008). Beyond Wnt inhibition: new functions of secreted Frizzled-related proteins in development and disease. J Cell Sci, 121(Pt 6), 737-746. Retrieved from https://www.ncbi.nlm.nih.gov/pubmed/18322270. doi:10.1242/jcs.026096

Cao, T. T., Xiang, D., Liu, B. L., Huang, T. X., Tan, B. B., Zeng, C. M., . . . Fu, L. (2017). FZD7 is a novel prognostic marker and promotes tumor metastasis via WNT and EMT signaling pathways in esophageal squamous cell carcinoma. Oncotarget, 8(39), 65957-65968. Retrieved from https://www.ncbi.nlm.nih.gov/pubmed/29029485. doi:10.18632/oncotarget.19586

Clevers, H., & Nusse, R. (2012). Wnt/beta-catenin signaling and disease. Cell, 149(6), 1192-1205. Retrieved from https://www.ncbi.nlm.nih.gov/pubmed/22682243. doi:10.1016/j.cell.2012.05.012

Ellwanger, K., Saito, H., Clement-Lacroix, P., Maltry, N., Niedermeyer, J., Lee, W. K., . . . Niehrs, C. (2008). Targeted disruption of the Wnt regulator Kremen induces limb defects and high bone density. Mol Cell Biol, 28(15), 4875-4882. Retrieved from https://www.ncbi.nlm.nih.gov/pubmed/18505822. doi:10.1128/MCB.00222-08

Hua, Y., Yang, Y., Li, Q., He, X., Zhu, W., Wang, J., & Gan, X. (2018). Oligomerization of Frizzled and LRP5/6 protein initiates intracellular signaling for the canonical WNT/beta-catenin pathway. J Biol Chem, 293(51), 19710-19724. Retrieved from https://www.ncbi.nlm.nih.gov/pubmed/30361437. doi:10.1074/jbc.RA118.004434

Janda, C. Y., Waghray, D., Levin, A. M., Thomas, C., & Garcia, K. C. (2012). Structural basis of Wnt recognition by Frizzled. Science, 337(6090), 59-64. Retrieved from https://www.ncbi.nlm.nih.gov/pubmed/22653731. doi:10.1126/science.1222879

Jiang, X., Charlat, O., Zamponi, R., Yang, Y., & Cong, F. (2015). Dishevelled promotes Wnt receptor degradation through recruitment of ZNRF3/RNF43 E3 ubiquitin ligases. Mol Cell, 58(3), 522-533. Retrieved from https://www.ncbi.nlm.nih.gov/pubmed/25891077. doi:10.1016/j.molcel.2015.03.015

MacDonald, B. T., Tamai, K., & He, X. (2009). Wnt/beta-catenin signaling: components, mechanisms, and diseases. Dev Cell, 17(1), 9-26. Retrieved from https://www.ncbi.nlm.nih.gov/pubmed/19619488. doi:10.1016/j.devcel.2009.06.016

Nile, A. H., Mukund, S., Stanger, K., Wang, W., & Hannoush, R. N. (2017). Unsaturated fatty acyl recognition by Frizzled receptors mediates dimerization upon Wnt ligand binding. Proc Natl Acad Sci U S A, 114(16), 4147-4152. Retrieved from https://www.ncbi.nlm.nih.gov/pubmed/28377511. doi:10.1073/pnas.1618293114

Semenov, M. V., Zhang, X., & He, X. (2008). DKK1 antagonizes Wnt signaling without promotion of LRP6 internalization and degradation. J Biol Chem, 283(31), 21427-21432. Retrieved from https://www.ncbi.nlm.nih.gov/pubmed/18505732. doi:10.1074/jbc.M800014200

Zeng, H., Lu, B., Zamponi, R., Yang, Z., Wetzel, K., Loureiro, J., . . . Cong, F. (2018). mTORC1 signaling suppresses Wnt/beta-catenin signaling through DVL-dependent regulation of Wnt receptor FZD level. Proc Natl Acad Sci U S A, 115(44), E10362-E10369. Retrieved from https://www.ncbi.nlm.nih.gov/pubmed/30297426. doi:10.1073/pnas.1808575115