Wnt signaling pathway

A conserved cell-signaling system in which Wnt proteins regulate gene expression and cell behavior through β-catenin-dependent and β-catenin-independent routes.

Canonical Wnt pathway: The Wnt signaling route in which β-catenin accumulates and regulates transcription. This is the β-catenin-dependent branch that controls many Wnt-responsive genes.
Wnt proteins: Secreted, lipid-modified proteins that bind cell-surface receptors to regulate development and tissue behavior. They are the extracellular signals that activate the pathway.
Embryonic development: The process by which a fertilized egg develops into a structured embryo. Wnt cues help establish body patterns and guide cell fate during development.
Nusse and Varmus Wnt discovery: The identification of a mouse proto-oncogene homologous to the Drosophila wingless gene. This discovery linked the mammalian Wnt gene to the pathway’s name and cancer research.
Hedgehog signaling pathway: A conserved signaling system in which Hedgehog proteins regulate development through Patched and Smoothened receptors. Like Wnt, it patterns embryos, but it uses a distinct receptor and signal-transduction system.
β-catenin: A protein that links cadherins to the cytoskeleton and acts as a transcriptional co-regulator. Wnt signaling stabilizes β-catenin, allowing it to influence gene expression.
Porcupine (protein): An endoplasmic-reticulum enzyme that attaches lipid modifications to Wnt proteins. Wnt lipidation by Porcupine is required for efficient secretion and signaling.
Stem cell niche: The local cellular environment that regulates stem-cell maintenance and behavior. Wnt signals from niche cells can sustain or direct tissue stem cells.
Roel Nusse: A developmental biologist whose work helped identify Wnt genes and establish their signaling role. His research connected Wnt genetics in mice with developmental signaling.
Notch signaling pathway: A cell-contact-dependent signaling system in which Notch receptors regulate gene expression after ligand binding. Notch often controls neighboring-cell fate decisions through direct contact rather than secreted Wnt cues.

Linked from 20 pages