IQ 1 has many functions such as decreasing Wnt-stimulated phosphorylation, maintaining the pluripotency of murine ESCs, preventing PP2A/Nkd interaction and so on.IQ 1 maintains the pluripotency of murine ESCs in long-term culture in a Wnt-dependent manner. IQ 1 decreased Wnt-stimulated phosphorylation of p300 at Ser-89.IQ-1 binds to serine/threonine phosphatase PP2A and prevents PP2A/Nkd interaction.The binding of IQ 1 to PR72/130 leads to decreased phosphorylation of the coactivator protein p300 at Ser-89. IQ 1 thereby diminishes the β-catenin/p300 interaction and prevents β-catenin coactivator switching from CBP to p300.
References:
[1]. Miyabayashi T et al. Wnt/beta-catenin/CBP signaling maintains long-term murine embryonic stem cell pluripotency. Proc Natl Acad Sci U S A, 2007 Mar 27, 104(13):5668-73.