Yu et al recently reported their use of twin-spot mosaic analysis with repressible cell markers to track the development of clusters of neurons in Drosophila. This is an exciting avenue of research because development is so tightly linked to cell phenotype, and classifying all brain cell types is a major goal of neuroscience. Aside from reporting that their technique “worked,” some of the interesting findings of the paper were that, 1) Neurons of the same lineage (i.e., same progenitors) exist as clusters in the central brain and ventral nerve cord, and 2) There is a unit production of one, two, or a small cluster of mature neurons that arise from any given neuroblast. Determination is huge in the developing brain.
Yu HH, et al. 2009 Twin-spot MARCM to reveal the developmental origin and identity of neurons. Nature Neuroscience 12: 947-953.