MESD is essential for apical localization of megalin/LRP2 in the visceral endoderm.

ABSTRACT: Deletion of the Mesd gene region blocks gastrulation and mesoderm differentiation in mice. MESD is a chaperone for the Wnt co-receptors: low-density lipoprotein receptor-related protein (LRP) 5 and 6 (LRP5/6). We hypothesized that loss of Wnt signaling is responsible for the polarity defects observed in Mesd-deficient embryos. However, because the Mesd-deficient embryo is considerably smaller than Lrp5/6 or Wnt3 mutants, we predicted that MESD function extends more broadly to the LRP family of receptors. Consistent with this prediction, we demonstrated that MESD function in vitro was essential for maturation of the β-propeller/EGF domain common to LRPs. To begin to understand the role of MESD in LRP maturation in vivo, we generated a targeted Mesd knockout and verified that loss of Mesd bl

SUBMITTER: Lighthouse JK 

PROVIDER: S-EPMC3069535 | biostudies-literature | 2011 Mar

REPOSITORIES: biostudies-literature