Monday, June 17th, 2013
Xin Li and Ted Erclik from Desplan Lab published a full article in Nature, analyzing the medulla processes visual information coming from inner photoreceptors R7 and R8 and from lamina neurons in the Drosophila optic lobes. It contains approximately 40,000 neurons belonging to more than 70 different types. Here we describe how precise temporal patterning of neural progenitors generates these different neural types. Five transcription factors—Homothorax, Eyeless, Sloppy paired, Dichaete and Tailless—are sequentially expressed in a temporal cascade in each of the medulla neuroblasts as they age. Loss of Eyeless, Sloppy paired or Dichaete blocks further progression of the temporal sequence. We provide evidence that this temporal sequence in neuroblasts, together with Notch-dependent binary fate choice, controls the diversification of the neuronal progeny. Although a temporal sequence of transcription factors had been identified in Drosophila embryonic neuroblasts, our work illustrates the generality of this strategy, with different sequences of transcription factors being used in different contexts.
For more information, this NATURE article will be available on June 26, 2013