Journal: bioRxiv
Article Title: Stoichiometric transcription factor partnerships specify GABAergic neuron subtype identity
doi: 10.64898/2026.05.25.727662
Figure Lengend Snippet: A , Genomic distribution of SP9 ChIP-seq peaks based on data from ( ; ). Peaks localize predominantly to enhancer-like regions (77%), with smaller fractions at promoters (6.2%) and other regions (16.8%). B , Motif enrichment within SP9 peaks. Promoter-associated peaks (left) are enriched for GC-rich motifs recognized by KLF and SP factors, whereas enhancer-like peaks (right) are enriched for TAATT motifs recognized by DLX homeobox factors. Within each block: motif logos (left), − log 10 𝑃 -value and target/background percentage of peaks containing the motif (middle), and log 2 enrichment (right). C , Schematic of the motif scan-based classification of SP9 peaks. Peaks were grouped based on the presence of an SP motif only (direct binding), a DLX motif only (indirect binding via DLX), or both (cobinding). D , Coarse genomic annotation (enhancer, transcription start site (TSS), or other) of the four SP9 peak categories defined in (C): SP9+DLX (both motifs present), DLX (DLX motif only), Other, and SP9 (SP motif only). E , Fine genomic annotation (exon, intron, intergenic, promoter, UTR, other) of the same four peak categories. F , Intersection of DLX2 and SP9 ChIP-seq peaks from E13.5 mouse GE, based on data from ( ; ; ). Bar plot shows the number of overlapping and non-overlapping peaks per category (DLX2 only, overlap, SP9 only). G , Whole-mount X-Gal staining (blue) of E11.5 transgenic mouse embryos carrying VISTA enhancer reporters hs119 (near Arx ), hs170 (near Fign ), hs883 (near Sox6 ), and hs298 (near Dlx6os1 ) used in the luciferase assays in panels K-N and shown as genome browser tracks in panel H. Images from . H , Genome browser tracks showing ChIP-seq signal for SP9, DLX2, and DLX5 in E13.5 mouse GE at the Sp9 and Six3 promoters (highlighted in grey) and the VISTA enhancers hs119, hs170, hs883, and hs298 (highlighted in blue). Numbers below each track indicate the count of SP and DLX motifs within the selected regulatory element. Data from ( ; ; ). I-N , Luciferase reporter activity in N2A cells transfected with combinations of Sp9 and Dlx2 , Dlx5 , or Dlx6 as indicated, driven by the Sp9 promoter ( I ), Six3 promoter ( J ), or enhancer regions hs119 of Arx ( K ), hs170 of Fign ( L ), hs883 of Sox6 ( M ), and hs298 of Dlx6os1 ( N ). Bars represent mean ± s.e.m. of 9 (I,J,L-N) or 12 (K) replicates from 3 (I,J,L-N) or 4 (K) independent batches performed in triplicate; points indicate batch means. Statistical significance was assessed by two-way ANOVA with Tukey’s honestly significant difference (HSD) post hoc test. Exact 𝑃 -values are provided in Table S6.
Article Snippet: Mouse N2A neuroblastoma cells (Neuro2A cells, ECACC, 89121404), human HEK293FT (Thermo Fisher Scientific, R70007), mouse 3T3-L1 (CLS Cell line service, 400103) were cultured in Dulbecco’s modified Eagle medium (DMEM, Sigma, D6429) supplemented with 10% (v/v) fetal bovine serum (FBS, Sigma, F9665) and containing 1% (v/v) antibiotics (100 Uml −1 penicillin, 100 μgmL −1 streptomycin, Sigma, P0781).
Techniques: ChIP-sequencing, Blocking Assay, Binding Assay, Staining, Transgenic Assay, Luciferase, Activity Assay, Transfection