Fzd7 Conditional Knockout mouse models

Fzd7, the mouse ortholog of human FZD7, encodes a seven-pass transmembrane Frizzled receptor whose extracellular cysteine-rich domain captures Wnt lipid-modified ligands and, together with Lrp5 or Lrp6, nucleates the signalosome that recruits Dishevelled through the intracellular KTXXXW motif. Because Fzd7 is enriched in intestinal and hepatic progenitors and is upregulated in triple-negative breast and hepatocellular tumors, it is a favored target for CRD-directed antibodies and decoy receptors, which makes the allele decision consequential: a conditional null asks whether a tissue depends on Fzd7-specific Wnt reception, a CRD humanization asks whether a clinical antibody engages its epitope and blocks ligand capture in vivo, and a signaling-dead tail mutant separates canonical output from planar cell polarity roles. Given that Fzd1, Fzd2, and Fzd5 bind overlapping Wnts and buffer single-receptor loss, compound conditional designs are prudent. Pair the chosen allele with a validated lineage driver such as Villin-Cre or Alb-Cre so the readout reflects the intended compartment.

A floxed Fzd7 allele paired with Cre gives spatial control that whole body knockouts cannot offer. People use it to separate developmental roles from adult homeostasis, to model somatic mutations, and to match disease that begins in one organ.