The neural progenitors exhibit self-renewing and multipotency and are capable to differentiate into diverse collection of neural cells such as neurons, astrocytes, and oligodendrocytes. The pathways regulating their survival, proliferation, differentiation, and migration are frequently disrupted or altered in many neurodegenerative disorders and brain tumors. Therefore, understanding the gene regulatory and signaling processes in neural development may provide directly knowledge relevant to neural degeneration and brain tumorigenesis and lead to novel therapies and strategies that will advance the treatment of these diseases. We are investigating how aberrant developmental processes contribute to degeneration and tumors with a particular focus on the role of Notch signaling pathway in regulating neural development, neural degeneration, and brain tumorigenesis.