GSK3 temporally regulates Neurogenin 2 proneural activity in the neocortex

Saiqun Li, Pierre Mattar, Dawn Zinyk, Kulwant Singh, Chandra Prakash Chaturvedi, Christopher Kovach, Rajiv Dixit, Deborah M. Kurrasch, Yong Chao Ma, Jennifer A. Chan, Valerie Wallace, F. Jeffrey Dilworth, Marjorie Brand, Carol Schuurmans*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

61 Scopus citations


The neocortex is comprised of six neuronal layers that are generated in a defined temporal sequence. While extrinsic and intrinsic cues are known to regulate the sequential production of neocortical neurons, how these factors interact and function in a coordinated manner is poorly understood. The proneural gene Neurog2 is expressed in progenitors throughout corticogenesis, but is only required to specify early-born, deep-layer neuronal identities. Here,weexaminedhowneuronal differentiation in general and Neurog2 function in particular are temporally controlled during murine neocortical development.Wefound that Neurog2 proneural activity declines in late corticogenesis, correlating with its phosphorylation by GSK3 kinase. Accordingly, GSK3 activity, which is negatively regulated by canonical Wnt signaling, increases over developmental time, while Wnt signaling correspondingly decreases. When ectopically activated, GSK3 inhibits Neurog2-mediated transcription in cultured cells and Neurog2 proneural activities in vivo. Conversely, a reduction in GSK3 activity promotes the precocious differentiation of later stage cortical progenitors without influencing laminar fate specification. Mechanistically, we show that GSK3 suppresses Neurog2 activity by influencing its choice of dimerization partner, promoting heterodimeric interactions with E47 (Tcfe2a), as opposed to Neurog2-Neurog2 homodimer formation, which occurs when GSK3 activity levels are low. At the functional level, Neurog2-E47 heterodimers have a reduced ability to transactivate neuronal differentiation genes compared with Neurog2-Neurog2 homodimers, both in vitro and in vivo. We thus conclude that the temporal regulation of Neurog2-E47 heterodimerization by GSK3 is a central component of the neuronal differentiation "clock" that coordinates the timing and tempo of neocortical neurogenesis in mouse.

Original languageEnglish (US)
Pages (from-to)7791-7805
Number of pages15
JournalJournal of Neuroscience
Issue number23
StatePublished - Jun 6 2012

ASJC Scopus subject areas

  • General Neuroscience


Dive into the research topics of 'GSK3 temporally regulates Neurogenin 2 proneural activity in the neocortex'. Together they form a unique fingerprint.

Cite this