First Author | Winkel A | Year | 2008 |
Journal | Cell Signal | Volume | 20 |
Issue | 11 | Pages | 2134-44 |
PubMed ID | 18762249 | Mgi Jnum | J:259108 |
Mgi Id | MGI:6148351 | Doi | 10.1016/j.cellsig.2008.08.009 |
Citation | Winkel A, et al. (2008) Wnt-ligand-dependent interaction of TAK1 (TGF-beta-activated kinase-1) with the receptor tyrosine kinase Ror2 modulates canonical Wnt-signalling. Cell Signal 20(11):2134-44 |
abstractText | Mutations in the receptor tyrosine kinase Ror2 account for Brachydactyly type B and Robinow Syndrome. We have identified two novel factors interacting with the Ror2 intracellular domain. TAK1 (TGF-beta activated kinase 1), a MAP3K, interacts with Ror2 and phosphorylates its intracellular carboxyterminal serine/thronine/proline-rich (STP) domain. This TAK1-dependent phosphorylation of Ror2 induces phosphorylation of tyrosine-residues including a MAPK-like TGY-motif. The TAK1-dependent phosphorylation is enhanced by a second cytosolic factor, PRTB, which interacts with Ror2 and with TAK1 as well. The TAK1-dependent Tyr-phosphorylation of Ror2 is not mediated by the Ror2 tyrosine kinase domain and seems predominantly triggered by cytosolic kinases. Wnt-ligand binding differentially controls the Ror2/TAK1 interaction. Wnt1-binding displaces TAK1 from Ror2 while Wnt3a and Wnt5a are unable to do so thus modifying TAK1''s capacity to cause phosphorylation of Ror2. Ror2 seems to act as a Wnt co-receptor enhancing Wnt-dependent canonical pathways while Tyr- and Ser/Thr-phosphorylation of Ror2 negatively controls the efficiency of these pathways. We propose that the level of the Wnt-ligand-regulated phosphorylation by cytosolic factors determines whether Ror2 acts as a stimulator or as an inhibitor of canonical Wnt-signalling. |