Notch Signaling Pathway

Notch proteins are single-pass transmembrane receptors with an extracellular domain that binds the ligand, a transmembrane domain that spans the plasma membrane, and an intracellular domain that acts in signaling.

These receptors act to control cell fate decisions, such as proliferation or apoptosis, in many tissues.

They do this by regulating multiple specific target genes that are critical during animal embryonic development, as well as for adult homeostasis.

Because of their critical functions, the notch signaling pathway is a highly conserved cell signaling system present in most animals.

Notch signaling requires direct cell-to-cell interaction and is controlled by three critical cleavages of the notch protein.

The first proteolytic cleavage of the Notch protein happens in the Golgi apparatus of the responding cell, and this generates a heterodimeric Notch receptor, which is then transported to the cell surface as a Notch receptor.

The second proteolytic cleavage occurs when a Delta-Serrate ligand expressed on a signaling cell interacts with the Epidermal growth factor-like repeats present on the extracellular domain of the Notch receptor.

Once bound, the Delta protein undergoe