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Dause, T. J.

Publications and source records attributed to Dause, T. J..

2 recordsLinked to original sources

Intracrine Vascular Endothelial Growth Factor Maintains Hippocampal Neural Stem Cell Quiescence

The vasculature is a key component of adult brain neural stem cell (NSC) niches. In the adult mammalian hippocampus, NSCs reside in close contact with a dense capillary network. How this niche is maintained is unclear. We recently found that adult hippocampal NSCs express vascular endothelial growth factor (VEGF), a soluble factor with chemoattractive properties for vascular endothelia. Here, we show that NSC-specific VEGF loss led to dissociation of NSCs from local vasculature but surprisingly found no changes in vascular density. Instead, we found that NSC-derived VEGF supports the motility of NSCs themselves via a cell internal signaling loop. We further found that this internal autocrine loop also independently maintained NSC quiescence cell autonomously. Combined, our findings suggest that NSCs maintain their populations via 2 mechanisms that are dependent on cell internal VEGF signaling: self-stimulated motility towards vasculature and cell autonomous maintenance of quiescence programs.

neuroscience↗

Poor concordance of floxed sequence recombination in single neural stem cells: Implications for cell autonomous studies

To manipulate target gene function in specific adult cell populations, tamoxifen-dependent CreERT2 is widely used to drive inducible, site-specific recombination of LoxP flanked sequences. In studies of cell autonomous target gene function, it is common practice to combine these CreERT2-lox systems with a ubiquitously-expressed stop-floxed fluorescent reporter gene to identify single cells supposedly undergoing target gene recombination. Here, we studied the reliability of using Cre-induced recombination of one gene to predict recombination in another gene at the single cell level in adult hippocampal neural stem and progenitor cells. Using two separate stop-floxed reporters plus a Nestin promoter-driven CreERT2, we found that, in individual cells, expression of one reporter was a poor predictor of expression of the other. These findings imply that use of stop-floxed reporters to investigate cell autonomous gene function is likely to lead to false conclusions because recombination in separate genes shows poor concordance in individual cells.

neuroscience↗