Notch proteins are transmembrane receptor that regluate cell fate decisions. Four Notch homologs have been identified in mammals namely Notch 1, Notch 2, Notch 3 and Notch 4. The membrane ligand for Notch includes Jagged 1, Jagged 2 and Delta. Notch 1 is a 270 kDa transmembrane receptor that can be activated by Delta (Dl) ligand. Activation of Notch 1 will result in the proteolytic cleavage of Notch 1 into a 120 kDa length protein.
