Final answer:
Notch receptors are activated through interaction with their specific ligands, leading to the release of the Notch intracellular domain (NICD), which then migrates to the nucleus to regulate transcription.
Step-by-step explanation:
Activation of Notch Receptors and Regulation of Transcription
Notch receptors are activated through interaction with their ligand on a neighboring cell. Upon activation, the intracellular portion of the Notch receptor is released through a regulated intramembrane proteolysis. This freed intracellular domain, known as Notch intracellular domain (NICD), then migrates to the cell's nucleus.
In the nucleus, NICD forms a complex with DNA-binding proteins and acts as a transcription factor. It regulates gene expression by binding to CIS-acting regulatory sequences like enhancers and promoters, turning on or inhibiting the transcription of target genes. This process is essential for cell fate determination and plays a critical role in the developmental process.