FZD4 Antibody – Rabbit Polyclonal

FZD4: Receptor for Wnt proteins. Most of frizzled receptors are coupled to the beta-catenin (CTNNB1) canonical signaling pathway, which leads to the activation of disheveled proteins, inhibition of GSK-3 kinase, nuclear accumulation of beta-catenin (CTNNB1) and activation of Wnt target genes. Plays a critical role in retinal vascularization by acting as a receptor for Wnt proteins and norrin (NDP). In retina, it can be both activated by Wnt protein-binding, but also by a Wnt-independent signaling via binding of norrin (NDP), promoting in both cases beta-catenin (CTNNB1) accumulation and stimulation of LEF/TCF-mediated transcriptional programs. A second signaling pathway involving PKC and calcium fluxes has been seen for some family members, but it is not yet clear if it represents a distinct pathway or if it can be integrated in the canonical pathway, as PKC seems to be required for Wnt-mediated inactivation of GSK-3 kinase. Both pathways seem to involve interactions with G-proteins. May be involved in transduction and intercellular transmission of polarity information during tissue morphogenesis and/or in differentiated tissues. Defects in FZD4 are the cause of vitreoretinopathy exudative type 1 (EVR1); also known as autosomal dominant familial exudative vitreoretinopathy (FEVR) or Criswick- Schepens syndrome. EVR1 is a disorder of the retinal vasculature characterized by an abrupt cessation of growth of peripheral capillaries, leading to an avascular peripheral retina. This may lead to compensatory retinal neovascularization, which is thought to be induced by hypoxia from the initial avascular insult. New vessels are prone to leakage and rupture causing exudates and bleeding, followed by scarring, retinal detachment and blindness. Clinical features can be highly variable, even within the same family. Patients with mild forms of the disease are asymptomatic, and their only disease-related abnormality is an arc of avascular retina in the extreme temporal periphery. Belongs to the G-protein coupled receptor Fz/Smo family.

Protein type: Receptor, GPCR; Membrane protein, integral; GPCR, Fz/Smo family; Membrane protein, multi-pass

Chromosomal Location of Human Ortholog: 11q14.2

Cellular Component: cell surface; integral to plasma membrane; integral to membrane; plasma membrane; intercellular junction

Molecular Function: G-protein coupled receptor activity; Wnt-protein binding; protein binding; Wnt receptor activity; protein homodimerization activity; protein heterodimerization activity; cytokine binding; ubiquitin protein ligase binding; PDZ domain binding

Biological Process: neuron differentiation; positive regulation of JNK activity; G-protein coupled receptor protein signaling pathway; Wnt receptor signaling pathway, calcium modulating pathway; Wnt receptor signaling pathway; sensory perception of sound; positive regulation of transcription, DNA-dependent; regulation of vascular endothelial growth factor receptor signaling pathway; positive regulation of transcription factor activity; Wnt receptor signaling pathway through beta-catenin; vasculogenesis; progesterone secretion; locomotion during locomotory behavior

Disease: Exudative Vitreoretinopathy 1