JAG1 (Jagged 1): JAG1 is a key ligand in the Notch signaling pathway, involved in cell fate determination and tissue development. Mutations in JAG1 can lead to Alagille syndrome, a disorder affecting the liver, heart, and other organs. Its role in Notch signaling also implicates JAG1 in diverse processes, including vascular development, hematopoiesis, and cancer progression....