Dataset Information

Distinct temporal requirements for the homeobox gene Gsx2 in specifying striatal and olfactory bulb neuronal fates.

ABSTRACT: The homeobox gene Gsx2 (formerly Gsh2) is known to be required for striatal and olfactory bulb neurogenesis; however, its specific role in the specification of these two neuronal subtypes remains unclear. To address this, we have employed a temporally regulated gain-of-function approach in transgenic mice and found that misexpression of Gsx2 at early stages of telencephalic neurogenesis favors the specification of striatal projection neuron identity over that of olfactory bulb interneurons. In contrast, delayed activation of the Gsx2 transgene until later stages exclusively promotes olfactory bulb interneuron identity. In a complementary approach, we have conditionally inactivated Gsx2 in a temporally progressive manner. Unlike germline Gsx2 mutants, which exhibit severe alterations in both striatal and olfactory bulb neurogenesis at birth, the conditional mutants exhibited defects restricted to olfactory bulb interneurons. These results demonstrate that Gsx2 specifies striatal projection neuron and olfactory bulb interneuron identity at distinct time points during telencephalic neurogenesis.

SUBMITTER: Waclaw RR

PROVIDER: S-EPMC2772064 | biostudies-literature | 2009 Aug

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Distinct temporal requirements for the homeobox gene Gsx2 in specifying striatal and olfactory bulb neuronal fates.

Waclaw Ronald R RR Wang Bei B Pei Zhenglei Z Ehrman Lisa A LA Campbell Kenneth K

Neuron 20090801 4

The homeobox gene Gsx2 (formerly Gsh2) is known to be required for striatal and olfactory bulb neurogenesis; however, its specific role in the specification of these two neuronal subtypes remains unclear. To address this, we have employed a temporally regulated gain-of-function approach in transgenic mice and found that misexpression of Gsx2 at early stages of telencephalic neurogenesis favors the specification of striatal projection neuron identity over that of olfactory bulb interneurons. In c ...[more]

PMID: 19709628

Similar Datasets

Project description:Olfactory bulb (OB) interneurons are known to represent diverse neuronal subtypes, which are thought to originate from a number of telencephalic regions including the embryonic dorsal lateral ganglionic eminence (dLGE) and septum. These cells migrate rostrally toward the OB, where they then radially migrate to populate different OB layers including the granule cell layer (GCL) and the outer glomerular layer (GL). Although previous studies have attempted to investigate regional contributions to OB interneuron diversity, few genetic tools have been used to address this question at embryonic time points when the earliest populations are specified.In this study, we utilized Zic3-lacZ and Gsx2e-CIE transgenic mice as genetic fate-mapping tools to study OB interneuron contributions derived from septum and LGE, respectively. Moreover, to address the regional (i.e. septal) requirements of the homeobox gene Gsx2 for OB interneuron diversity, we conditionally inactivated Gsx2 in the septum, leaving it largely intact in the dLGE, by recombining the Gsx2 floxed allele using Olig2 Cre/+ mice.Our fate mapping studies demonstrated that the dLGE and septum gave rise to OB interneuron subtypes differently. Notably, the embryonic septum was found to give rise largely to the calretinin+ (CR+) GL subtype, while the dLGE was more diverse, generating all major GL subpopulations as well as many GCL interneurons. Moreover, Gsx2 conditional mutants (cKOs), with septum but not dLGE recombination, showed impaired generation of CR+ interneurons within the OB GL. These Gsx2 cKOs exhibited reduced proliferation within the septal subventricular zone (SVZ), which correlated well with the reduced number of CR+ interneurons observed.Our findings indicate that the septum and LGE contribute differently to OB interneuron diversity. While the dLGE provides a wide range of OB interneuron subtypes, the septum is more restricted in its contribution to the CR+ subtype. Gsx2 is required in septal progenitors for the correct expansion of SVZ progenitors specified toward the CR+ subtype. Finally, the septum has been suggested to be the exclusive source of CR+ interneurons in postnatal studies. Our results here demonstrate that dLGE progenitors in the embryo also contribute to this OB neuronal subtype.

Dataset Information

Distinct temporal requirements for the homeobox gene Gsx2 in specifying striatal and olfactory bulb neuronal fates.

Publications

Distinct temporal requirements for the homeobox gene Gsx2 in specifying striatal and olfactory bulb neuronal fates.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets