Project description:Purpose: This study seeks to determine whether Smarcc1 mediates GLI repression through chromatin compaction in the limb. Methods: To determine if Smarcc1 mediated GLI repression through chormatin compaction, we used genomic approached to determine changes in chromatin accessibility in control and Smarcc1-conditional mutants. We performed ATAC-seq on individually genotyped anterior forelimbs at E11.5 (40-48s) on control (2 replicates) and PrxCre/+;Smarcc1c/c (3 replicates) embryos. From this experiment we identified ~10,000 differentially accessible regions (FDR<0.05). Results: We find that SMARCC1 is required to maintain chromatin accessibility at thousands of regions within the mouse limb, including most HH-responsive GLI enhancers
Project description:Purpose: This study seeks to determine whether Smarcc1 co-regulates Hedgehog (HH) target genes in the limb. Methods: To determine if Smarcc1 is required to regulate HH targets, we used genomic approaches to identify Smarcc1-regulated genes within the forelimb. We performed bulk RNA-seq on individually genotyped forelimb-bud pairs at E11.5 (39-40s) on control (2 replicates) and PrxCre/+;Smarcc1c/c (2 replicates) embryos. From this experiment we identified 928 differentially expressed genes (FDR<0.05). Results: We find that while certain HH target genes are co-regulated by SMARCC1, the majority of HH target genes do not require Smarcc1.
Project description:Purpose: This study seeks to identify SMARCC1-bound regions in the mouse limb. Methods: To identify SMARCC1 bound regions in the limb, we performed Cut&Run on pooled anterior and posterior wild-type forelimbs at E11.5 (43-44s; 3 replicates each) and on whole forelimb pairs at E9.5 (21-24s; 2 replicates). We identified 28,082 SMARCC1-bound regions in the anterior forelimb at E11.5, 42,530 regions in the E11.5 posterior limb, and 10,792 SMARCC1-bound regions at E9.5 (FDR<0.05). Results: We find that SMARCC1 is bound to most limb enhancer regions at late stages (E11.5). Additionally, We find that SMARCC1 is bound to the majority of HH-responsive GLI enhancers at E11.5 but only a small portion of GLI enhancers at E9.5.
Project description:Transcriptional responses to the Hedgehog (HH) signaling pathway are primarily modulated by GLI repression in the mouse limb. Previous studies suggested a role for the BAF chromatin remodeling complex in mediating GLI repression. Consistent with this possibility, the core BAF complex protein SMARCC1 is present at most active limb enhancers including the majority of GLI enhancers. However, in contrast to GLI repression which reduces chromatin accessibility, SMARCC1 maintains chromatin accessibility at most enhancers, including those bound by GLI. Moreover, SMARCC1 binding at GLI-regulated enhancers occurs independently of GLI3. Consistent with previous studies, some individual GLI target genes are mis-regulated in Smarcc1 conditional knockouts, though most GLI target genes are unaffected. Moreover, SMARCC1 is not necessary for mediating constitutive GLI repression in HH mutant limb buds. We conclude that SMARCC1 does not mediate GLI3 repression, which we propose utilizes alternative chromatin remodeling complexes.
Project description:Purpose: This study seeks to determine whether GLI3 is required to recruit the SMARCC1 complex to GLI enhancers in the limb. Methods: To determine if Gli3 is required to recruit SMARCC1 to its anhancers, we performed differential chromatin binding to compare SMARCC1 binding in control and Gli3 mutants. We performed Cut&Run for SMARCC1 binding on individually genotyped E11.5 (40-43s) anterior forelimb pairs from control (Gli3+/+; 3 replicates) and Gli3 mutant (Gli3-/-; 4 replicates) embryos. Results: We found that there is no major difference in SMARCC1 binding in Gli3-mutants compared to controls.
