Adult neurogenesis, the process of generating mature neurons from neuronal progenitor cells, makes critical contributions to neural circuitry and brain function in both healthy and disease states. Neurogenesis is a highly regulated process in which diverse environmental and physiological stimuli are relayed to resident neural stem cell populations to control the transcription of genes involved in self-renewal and differentiation. Understanding the molecular mechanisms governing neurogenesis is necessary for the development of translational strategies to harness this process for neuronal repair. Here we report that the Ras-related GTPase RIT1 serves to control the sequential proliferation and differentiation of adult hippocampal neural progenitor cells, with in vivo expression of active RIT1 driving robust adult neurogenesis. Gene expression profiling analysis demonstrates increased expression of a specific set of transcription factors known to govern adult neurogenesis in response to active RIT1 expression in the hippocampus, including sex-determining region Y-related HMG box 2 (Sox2), a well established regulator of stem cell self-renewal and neurogenesis. In adult hippocampal neuronal precursor cells, RIT1 controls an Akt-dependent signaling cascade, resulting in the stabilization and transcriptional activation of phosphorylated Sox2. This study supports a role for RIT1 in relaying niche-derived signals to neural/stem progenitor cells to control transcription of genes involved in self-renewal and differentiation.
|Number of pages||11|
|Journal||Journal of Biological Chemistry|
|State||Published - Feb 10 2017|
Bibliographical noteFunding Information:
This work was supported in part by NINDS, National Institutes of Health Grant R01 NS045103, Kentucky Spinal Cord and Head Injury Research Trust Grant 12-1A, and a Kentucky Lung Cancer research grant. The authors declare that they have no conflicts of interest with the contents of this article. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health. We thank Dr. Wang Chi and Yu Chin (Markey Cancer Center, University of Kentucky) for help with the generation of heat maps. We also acknowledge Linda Simmerman (Spinal Cord and Brain Injury Center) and Carole Moncman (Department of Molecular and Cellular Biochemistry) for help with confocal microscopy.
© 2017 by The American Society for Biochemistry and Molecular Biology, Inc.
ASJC Scopus subject areas
- Molecular Biology
- Cell Biology