Journal: Neuron

Article Title: CONSERVED HIGHER ORDER CHROMATIN REGULATES NMDA RECEPTOR GENE EXPRESSION AND COGNITION

doi: 10.1016/j.neuron.2014.10.032

Figure Lengend Snippet: (A) 500kb of linear genome (mm9, chromosome 6:135,623,529-136,123,529), encompassing Grin2b, including TSS (green), proximal intronic sequences targeted by SETDB1 (yellow), and two loop loopings (red) (1) Grin2bTSS+378kb and (2) Grin2bTSS+471kb, with sequences homologue to human GRIN2BTSS+348kb and GRIN2BTSS+449kb (Fig. S1) (B) (Top) Browser tracks for histone marks H3K4me3 and H3K27ac in adult mouse cerebral cortex(Dixon et al., 2012). (C) Fold-change (CK-Setdb1 transgenic (Tg) /wildtype littermate (Wt) of 3C PCR from adult Tg and Wt cortex (see also Fig. S2). Notice increased physical interactions of (yellow) TSS-bound +15 to +40kb intronic sequence, and significant decrease in (red box no. 1) Grin2bTSS+378kb and (red box no. 2) Grin2bTSS+471kb. Two-way ANOVA, 3C interaction × genotype F(7,32)=54.905(p<0.001). Newman-Keuls post-hoc *, **; P< 0.05, 0.01. (D) Quantification of Grin2b (left) RNA and (right) protein in adult (6–8 week) CK-Setdb1 Tg and wildtype (Wt) littermate control cortex. mean ± S.D, N=5 (RNA) and N=3 (immunoblot)/group. (E) Activity-dependent regulation of Grin2b higher order chromatin in hippocampal neurons. (top, left to right) Grin2b RNA, 3C quantification of Grin2bTSS+378kb and Grin2bTSS+471kb and SETDB1 occupancy across four regulatory sequences at Grin2b locus. Note significant increase at SETDB1 target site after 15 hours of picrotoxin (PTX) or vehicle control (DMSO). N=3–6 experiments/group, data shown as mean ± S.D..(F) (left) Grin2b-TALE-VP64-GFP specifically targets mouse Grin2b loop no. 2 (Grin2bTSS+471kb), 471 kb downstream of TSS. Images show Neuro2A cells and cultured hippocampal neurons expressing GFP-tagged TALE-VP64. RT-PCR for Grin2b and Gapdh control showing specific expression in cultured neurons. (right) anti-TALE-VP64 ChIP in N2A and NG108 cells and primary cortical neurons, expressed (y-axis) as fold change compared to non-transfected condition (N=3/group; (mean ± S.E.M., * Two-way ANOVA cell type × TALE-VP64 binding F(2,12)=4.04, P<0.05, Bonferroni posthoc P < 0.05).RT-PCR Grin2b, Grin2a and Setdb1 RNA levels in neurons transfected with TALE-VP64-EGFP (TALE), compared to mock-transfected neurons (Con). Notice specific TALE-VP64 mediated increase in Grin2b RNA (N = 6 per group, mean ± S.E.M, *P < 0.05, t-test). See also Figures S1 and S2.

Article Snippet: TALE-based designer transcription factor Two Transcription Activator-Like Element DNA-binding proteins (TALE), fused to four tandem copies of the Herpes simplex Viral protein 16, amino acids 437–447, DALDDFDLDML connected with glycine-serine linkers, were targeted to intergenic sequences in the mouse genome, 471 kb downstream of the Grin2b TSS using the TALE tool box kit (Addgene).

Techniques: Transgenic Assay, Sequencing, Control, Western Blot, Activity Assay, Cell Culture, Expressing, Reverse Transcription Polymerase Chain Reaction, Transfection, Binding Assay