Ezrin is a member from the ERM (Ezrin-Radixin-Moesin) category of Amsacrine membrane-cytoskeletal linking protein. locations previously never have been characterized. Within this study we used immunocytochemistry to perform double labeling with a variety of cell-type specific markers to characterize the expression Amsacrine of ezrin in the adult SVZ and RMS. Ezrin was expressed at high levels in both the SVZ and RMS where ezrin-immunopositive processes formed a trabecular network surrounding the proliferating and migrating cells. Ezrin-positive cells co-labeled with the glial makers S100β and GFAP (glial fibrillary acidic protein) but only minimally with the early neuronal markers β III tubulin and PSA-NCAM indicating that ezrin was expressed primarily in the glial tube cells. Ezrin positive cells also expressed β-catenin a membrane-complex protein previously implicated in the regulation of stem-cell proliferation and neuronal migration. Glial tube cells act as both precursors of and a physical channel for migrating neuroblasts. Bi-directional signals between glial tube cells and migrating neuroblasts have been shown to regulate the rates of both proliferation of the precursor cells and migration of the newly generated neuroblasts. Our finding that ezrin and β-catenin are both present at the cell membrane of the glial tube cells suggests that these proteins may be involved in those signaling processes. hybridization study showed ezrin mRNA expression in neurogenic regions of the mature brain including the SVZ and RMS (Gimeno et al. 2004 However the Rabbit Polyclonal to Retinoblastoma. specific cell types expressing ezrin and their relationship to migrating and proliferating cells in these regions have not been characterized previously. In this study we used immunocytochemistry to perform double labeling with a variety of cell-type specific markers including the glial markers S100β and GFAP and the early neuronal markers β III tubulin (Peretto et al. 1997 and PSA-NCAM (Hu et al. 1996 to characterize the expression of ezrin in the adult SVZ and RMS. The thymidine analog bromodeoxyuridine (BrdU) was also used to label dividing cells to investigate the relationship of ezrin-expressing cells to the proliferating and migrating cells in the SVZ and RMS. We also investigated the expression of β-catenin another membrane-cytoskeletal linking protein that has previously been implicated in the regulation of proliferation in both SVZ and other stem-cell populations (Chenn and Walsh 2002 Chenn and Walsh 2003 Gavard et al. 2004 He et al. 2004 Reya and Clevers 2005 We found Amsacrine that both ezrin and β-catenin were expressed primarily in glial tube cells. Bidirectional signals between glial tube cells and migrating neuroblasts have been shown to regulate the rates of both proliferation of the precursor cells and migration of the newly produced neuroblasts (Bolteus and Bordey 2004 Liu et al. 2005 Amsacrine Amsacrine Our discovering that ezrin and β-catenin are both present on the cell membrane from the glial pipe cells shows that these protein may be involved with those signaling procedures. Materials and Strategies All procedures concerning animals had been performed in tight accordance using the NIH Information for the Treatment and Usage of Lab Animals and had been accepted by the Yale Pet Care and Make use of Committee. BrdU Labeling and Tissues Planning Mice received an individual intraperitoneal shot of BrdU (75 mg/kg) (Roche Diagnostics Indianapolis IN). Two hrs afterwards mice had been deeply anesthetized with chloral hydrate and perfused transcardially with 4% paraformaldehyde. Brains had been dissected post-fixed for 48 hrs in 4% paraformaldehyde cryoprotected in 30% sucrose and lower into serial Amsacrine 30-μm coronal or parasagittal areas on the freezing microtome. Major Antibodies and Immunofluorescence Major antibodies had been bought from BD Pharmingen (NORTH PARK CA) Cell Signaling Technology (Beverly MA) Chemicon (Temecula CA) Sigma-Aldrich.