The Drosophila Sp8 transcription factor buttonhead prevents premature differentiation of intermediate neural progenitors
Abstract
Intermediate neural progenitor cells (INPs) need to avoid differentiation and cell cycle exit while maintaining restricted developmental potential, but mechanisms preventing differentiation and cell cycle exit of INPs are not well understood. Here we report that the Drosophila homolog of mammalian Sp8 transcription factor Buttonhead (Btd) prevents premature differentiation and cell cycle exit of INPs in Drosophila larval type II neuroblast (NB) lineages. We show that loss of Btd leads to elimination of mature INPs due to premature differentiation of INPs into terminally dividing ganglion mother cells. We provide evidence to demonstrate that Btd prevents the premature differentiation by suppressing the expression of the homeodomain protein Prospero in immature INPs. We further show that Btd functions cooperatively with the Ets transcription factor Pointed P1 to promote the generation of INPs. Thus, our work reveals a critical mechanism that prevents premature differentiation and cell cycle exit ofDrosophila INPs.
Article and author information
Author details
Reviewing Editor
- Marianne E Bronner, California Institute of Technology, United States
Publication history
- Received: June 7, 2014
- Accepted: September 28, 2014
- Accepted Manuscript published: October 6, 2014 (version 1)
- Version of Record published: November 6, 2014 (version 2)
Copyright
© 2014, Xie et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Further reading
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- Stem Cells and Regenerative Medicine
- Developmental Biology
In the developing fruit fly brain, a protein called Trithorax increases the number of neural cells produced from a single stem cell, in part by regulating the transcription of the target genes buttonhead and pointed.
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- Cell Biology
- Developmental Biology
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