Decoding neuronal diversity: Mechanisms governing neural cell fate in Drosophila.

Generating neuronal diversity from a limited number of neural stem cells is fundamental for the proper functioning of the brain. However, the mechanisms that govern neural fate determination have long been elusive due to the intricate interplay of multiple independent factors that influence a cell's commitment to specific fates. While classical genetics and labeling tools have laid the groundwork for identifying cell types and understanding neural complexity, recent breakthroughs in single-cell transcriptomics and whole-brain connectomics represent a significant advancement in enabling a comprehensive characterization of brain cell types and the underlying mechanisms that encode these neuronal identities. This review focuses on recent developments in our understanding of neural cell fate determination in Drosophila, emphasizing three key mechanisms: spatial patterning, temporal patterning, and neuron-type specific terminal selector transcription factors.