Project description:We conducted RNA-Seq and in situ hybridization to identify transcriptional profile changes in the Sp8/Sp9-DCKO olfactory bulb. Simultaneously, we did ChIP-Seq with homemade Sp9 antibody to identify Sp9 binding motifs and which changed genes might be the direct targets of transcription factor Sp9. We found that Sp9 directly binded to key genes which are required for olfactory bulb development. Transcription factors Sp8 and Sp9 belong to the same transcription factor family, so we think Sp8 and Sp9 have very similar binding sites of transcriptional regulation.
Project description:Generation of olfactory bulb (OB) interneurons requires neural stem/progenitor cell specification, proliferation, differentiation, and young interneuron migration and maturation. Here, we show that the homeobox transcription factors Dlx1/2 are central and essential components in the transcriptional code for generating OB interneurons. In Dlx1/2 constitutive null mutants, the differentiation of GSX2+ and ASCL1+ neural stem/progenitor cells in the dorsal lateral ganglionic eminence is blocked, resulting in a failure of OB interneuron generation. In Dlx1/2 conditional mutants (hGFAP-Cre; Dlx1/2F/- mice), GSX2+ and ASCL1+ neural stem/progenitor cells in the postnatal subventricular zone also fail to differentiate into OB interneurons. In contrast, overexpression of Dlx1&2 in embryonic mouse cortex led to ectopic production of OB-like interneurons that expressed Gad1, Sp8, Sp9, Arx, Pbx3, Etv1, Tshz1 and Prokr2. Pax6 mutants generate cortical ectopia with OB-like interneurons, but do not do so in compound Pax6; Dlx1/2 mutants. We propose that DLX1/2 promote OB interneuron development mainly through activating the expression of Sp8/9, which further promote Tshz1 and Prokr2 expression. Based on this study, in combination with earlier ones, we propose a transcriptional network for the process of OB interneuron development. This SuperSeries is composed of the SubSeries listed below.
Project description:Purpose: To asses changes in gene expression profiles from the P11 no cre littermate control olfactory bulbs and conditional double knockout olfactory bulbs of Dlx5/6-CIE; Sp8 Flox/Flox; Sp9 Flox/Flox (Sp8/Sp9-DCKO) mice. Methods: Total RNA was isolated and sequenced from the olfactory bulbs of the P11 no cre littermate controls or Sp8/Sp9-DCKO mice in duplicate using an illumina high-seq 2500. Raw data was analyzed using TopHat. Genes were considered changed which performed fold-change>=2 and FDR<=0.05. Changed genes were then filtered to reveal the downstream targets of Sp8 and Sp9. Results: 32 genes were significantly increased and 144 genes were significantly decreased in expression level due to the loss of Sp9 and Sp8 expression.
Project description:Purpose: To asses changes in gene expression profiles from the P30 wild type littermate control olfactory bulbs and conditional double knockout olfactory bulbs of hGFAP-Cre; Sp8 Flox/Flox; Sp9 Flox/Flox mice. Methods: Total RNA was isolated and sequenced from the olfactory bulbs of the P30 wild type littermate controls or hGFAP-Cre; Sp8 Flox/Flox; Sp9 Flox/Flox mice in tetrad using an illumina high-seq 2500. Raw data was analyzed using TopHat. Genes were considered changed which performed fold-change>=2 and FDR<=0.05. Changed genes were then filtered to reveal the downstream targets of Sp8 and Sp9. Results: 31 genes were significantly increased and 74 genes were significantly decreased in expression level due to the loss of Sp9 and Sp8 expression.
Project description:D1- and D2-type medium spiny neurons (MSNs) are the principal projection neurons in the striatum, including in the dorsal striatum (caudate nucleus and putamen) and ventral striatum (nucleus accumbens and olfactory tubercle) that are generated by the lateral ganglionic eminence (LGE). Using conditional deletion, we show that mice lacking the Sp8 and Sp9 transcription factors (TFs) selectively have a severe reduction in D2 MSNs due to reduced neurogenesis in the LGE. Sp8/9 together drive expression of the Six3 TF in a spatial restricted domain of the LGE subventricular zone. Conditional deletion of Six3 also prevents the formation of most D2 MSNs, phenocopying the Sp8/9 loss of function. Finally, ChIP-Seq reveals that SP9 directly binds to the promoter and a putative enhancer of Six3. This study provides evidence for components of a transcription pathway, in a regionally restricted LGE domain, that selectively drives the generation of D2 MSNs.
Project description:Purpose: To assess changes in gene expression profiles from the E16.5 no cre littermate control striatum and conditional double knockout of Dlx5/6-CIE; Sp8 Flox/Flox; Sp9 Flox/Flox mice. Methods: Total RNA was isolated and sequenced from the striatum of the E16.5 no cre littermate control or Dlx5/6-CIE; Sp8 Flox/Flox; Sp9 Flox/Flox mice in duplicate using an illumina high-seq 2500. Raw data was analyzed using TopHat. Genes were considered changed which performed fold-change>=2 and FDR<=0.05. Changed genes were then filtered to reveal the downstream targets of Sp8 and Sp9. Results: 80 genes were significantly increased and 120 genes were significantly decreased in expression level due to the loss of Sp8 and Sp9 expression.
Project description:Distinct neural stem cells reside in different regions of the subventricular zone and generate multiple olfactory bulb interneuron subtypes in the adult mouse brain. This study shows that the basic helix-loop-helix type transcription factor Olig2 defines a ventrally enriched subset of NSCs in the early postnatal and adult SVZ and plays an important role in the subtype specification of olfactory bulb interneurons produced by adult NSCs.