Distribution of doublecortin expressing cells near the lateral ventricles in the adult mouse brain

Abstract

Doublecortin (Dcx) is a microtubule-associated protein expressed by migrating neuroblasts in the embryo and in the adult subventricular zone (SVZ). The adult SVZ contains neuroblasts that migrate in the rostral migratory stream (RMS) to the olfactory bulbs. We have examined the distribution and phenotype of Dcx-positive cells in the adult mouse SVZ and surrounding regions. Chains of Dcx-positive cells in the SVZ were distributed in a tight dorsal population contiguous with the RMS, with a separate ventral population comprised of discontinuous chains. Unexpectedly, Dcx-positive cells were also found outside of the SVZ: dorsally in the corpus callosum, and ventrally in the nucleus accumbens, ventromedial striatum, ventrolateral septum, and bed nucleus of the stria terminalis. Dcx-positive cells outside the SVZ had the morphology of migrating cells, occurred as individual cells or in chain-like clusters, and were more numerous anteriorly. Of the Dcx-positive cells found outside of the SVZ, 47% expressed the immature neuronal protein class III beta-tubulin, 8% expressed NeuN, a marker of mature neurons. Dcx-positive cells did not express molecules found in astrocytes, oligodendrocytes, or microglia. Structural and immunoelectron microscopy revealed that cells with the ultrastructural features of neuroblasts in the SVZ were Dcx+, and that clusters of neuroblasts emanated ventrally from the SVZ into the parenchyma. Our results suggest that the distribution of cells comprising the walls of the lateral ventricle are more heterogeneous than was thought previously, that SVZ cells may migrate dorsally and ventrally away from the SVZ, and that some emigrated cells express a neuronal phenotype.

Cell Proliferation is Influenced by Bulbectomy and Normalized by Imipramine Treatment in a Region-Specific Manner

“…We found that the basal levels of cells incorporating BrdU in the hippocampus and SVZ of sham-operated control animals were consistent with those of previous reports (Kempermann and Gage, 2000;Mandairon et al, 2003;Brown et al, 2003;Yang et al, 2004). In the SVZ, BrdUpositive cells were concentrated in a tight band in the dorsal area (Figure 1a), and in a looser network of single cells in the ventral area.…”

GABA Release and Uptake Regulate Neuronal Precursor Migration in the Postnatal Subventricular Zone

“…It was also recently reported that TuJ1-positive cells in the SVZ and RMS stain positive for doublecortin, an additional neuronal precursor marker (Yang et al, 2004). The exclusive presence of neuronal precursors in the anterior SVZ and RMS is consistent with the time course of gliogenesis that ceases at ϳ14 -15 d of age in rats (Levison and Goldman, 1993).…”

Mosaic Removal of Hedgehog Signaling in the Adult SVZ Reveals That the Residual Wild-Type Stem Cells Have a Limited Capacity for Self-Renewal

“…5f-h). We also observed that in tamoxifentreated Nestin CreER/ϩ ; Smo c/c mice, the expression of Mash1 (C cell marker) (Parras et al, 2004), Dcx (A cell marker) (Francis et al, 1999;Gleeson et al, 1999;Englund et al, 2002;Brown et al, 2003;Yang et al, 2004) and GFAP (B cell marker, but also marker of mature astrocytes; Doetsch et al, 1997Doetsch et al, ,1999a is reduced (Fig. 6) Fig.…”