Desplan Lab
New York University. 100 Washington Square East.
1009 Silver Center. New York, NY. 10003.

Post-Doctoral Fellow

Xin Li

(212) 992-9529


  • 2006. Northwestern University. PhD.


  • The Drosophila optic lobe is composed of Lamina, Medulla and the Lobula complex. I am among a team studying the development of the Drosophila medulla, and I am focused on how temporal patterning of neural progenitors generates neural diversity in the main medulla region. We performed an antibody screen looking for transcription factors (TF) expressed in the developing medulla, and have identified a large set of TFs expressed in subsets of neural progenitors (neuroblasts: NBs) and neurons. We identified a temporal gene sequence, composed of five TFs: Homothorax, Eyeless, Sloppy-paired, Dichaete and Tailless, that are sequentially and transiently expressed in medulla NBs as they transit through different temporal stages. Loss of one TF blocks further progression of the temporal sequence and causes the NBs to be stuck at the preceding TF stage. With the exception of Hth, Notch-dependent asymmetric division of the intermediate progeny of NBs, the Ganglion Mother Cell (GMC), causes the NB TF to be transmitted and maintained in only half of the progeny. Most neuronal TF markers are also only expressed in one of the two daughters of a certain GMC. We are studying how the temporal TF sequence in NBs and the Notch-dependent binary fate choice together control the combinatorial expression of different TF markers in their neuronal progeny, and thus determine the sequential generation of different neuron types. For example, we found that the Non progeny of Hth+ GMCs express Apterous and Bsh, and become Mi1 local neurons; while the Noff progeny either commit apoptosis or adopt different neuronal fates depending on the spatial identity of the NBs. We are examining the fate of the progeny from NBs at other stages. The long term goal is to investigate how the NBs transit between these TF stages and generate neural diversity.


  • The Robert Leet and Clara Guthrie Patterson Trust Postdoctoral Fellowship Program in Brain Circuitry.