Project description:Purpose: Histone demethylase Kdm1a affected mouse SCLC progression through many down-stream factors or pathways. RNA-seq of mouse SCLC cell lines with or without Kdm1a knock-out was used to find the most enriched pathways in Kdm1a knock-out cells Methods: Total mRNA profiles of control (Crispr-V2) or Kdm1a knock-out mouse SCLC cell lines (Kdm1a-sg1, Kdm1a-sg2) were generated by deep sequencing, using Illumina Hiseq platform and 125 bp/150 bp paired-end reads. Index of the reference genome was built using Bowtie v2.2.3 and paired-end clean reads were aligned to the reference genome using TopHat v2.0.12. qRT–PCR validation was performed using TaqMan and SYBR Green assays Results: Using an optimized data analysis workflow, we mapped about 30 million sequence reads per sample to the mouse genome (build mm9). Commonly differential expression after Kdm1a knock-out with two different single guide RNAs to control mouse SCLC cells were selected with a fold change ≥1.5. Conclusions: Our data showed four Rest related pathways, including negative cell proliferation, negative cell differentiation, positive regulation of programmed cell death enriched, in commonly up-regulated genes after Kdm1a knock-out with twe different single guide RNAs. Meanwhile, the commonly down-regulated genes were mostly enriched in neron related pathways. These result illustrated the Kdm1a depletion inhibited mouse SCLC progression, defected its neuroendocrine phenotype through the up-regulation of Rest.
Project description:Using chromatin immuno-precipitation (ChIP) combined with deep sequencing (ChIP-seq) we obtained a time resolved and genome-wide map of BMAL1 binding in mouse liver, which allowed to identify over two thousand binding sites with peak binding narrowly centered around Zeitgeber time (ZT) 6. Annotation of BMAL1 targets confirms carbohydrate and lipid metabolism as the major output of the circadian clock in mouse liver. Moreover, transcription regulators are largely overrepresented, several of which also exhibit circadian activity. Genes of the core circadian oscillator stand out as strongly bound, often at promoter and distal sites. Genomic sequence analysis of the sites identified E- boxes and tandem E1-E2 consensus elements. Electromobility shift assays (EMSA) showed that E1-E2 sites are bound by a dimer of BMAL1/CLOCK heterodimers with a spacing-dependent cooperative interaction that was further validated in transactivation assays. BMAL1 target genes showed cyclic mRNA expression profiles with a phase distribution centered at ZT10. Importantly, sites with E1-E2 elements showed tighter phases both in binding and mRNA accumulation. Finally, comparing the temporal accumulation of precursor mRNA and mature mRNA helped distinguish direct BMAL1 targets from targets with more complex regulation, and showed how transcriptional and post-transcriptional regulation contribute differentially to circadian expression phase. Together, our analysis of a dynamic protein-DNA interactome uncovered how genes of the core circadian oscillator are wired together and drive phase-specific circadian output programs in a complex tissue. ChIP-Seq of BMAL1 in mouse liver during one circadian cycle at 4 hour time resolution presented in this Series (GSE26602). mRNA profiling data used in this study are already published (Kornmann et al, PLoS Biol 2007) and have been deposited on ArrayExpress repository (accession number: E-MEXP-842).
Project description:Purpose: The goal of this study is to identify genes and molecular pathways whose expression is altered in the livers of Gpr151 knock-out (KO) mice compared to Gpr151 wild-type (WT). Methods: Total RNA was isolated from livers of fasted (5h) 16-week-old male mice. Deep sequencing of RNA from three wild-type and three knock-out mice was done using the mRNA-Seq pipeline at Novogene. The sequence reads that passed quality filters were aligned to the mouse GRCm38.p6 genome using STAR 2.6.1d. Differential expression testing was conducted using DESeq2. Results: Using an optimized data analysis workflow, we mapped about 40 million sequence reads per sample to the mouse genome (build mm10) and identified 54,532 transcripts in the livers of Gpr151 WT and KO mice. RNA-seq data identified 79 transcripts which were significantly upregulated in KO (p-adj < 0.05, log2FoldChange>1) and 338 transcripts which were significantly downregulated (p-adj<0.05, log2FoldChange<-1) in KO. Conclusions: Our study represents the first detailed analysis of the liver transcriptome of Gpr151 KO mice.
Project description:Using chromatin immuno-precipitation (ChIP) combined with deep sequencing (ChIP-seq) we obtained a time resolved and genome-wide map of BMAL1 binding in mouse liver, which allowed to identify over two thousand binding sites with peak binding narrowly centered around Zeitgeber time (ZT) 6. Annotation of BMAL1 targets confirms carbohydrate and lipid metabolism as the major output of the circadian clock in mouse liver. Moreover, transcription regulators are largely overrepresented, several of which also exhibit circadian activity. Genes of the core circadian oscillator stand out as strongly bound, often at promoter and distal sites. Genomic sequence analysis of the sites identified E- boxes and tandem E1-E2 consensus elements. Electromobility shift assays (EMSA) showed that E1-E2 sites are bound by a dimer of BMAL1/CLOCK heterodimers with a spacing-dependent cooperative interaction that was further validated in transactivation assays. BMAL1 target genes showed cyclic mRNA expression profiles with a phase distribution centered at ZT10. Importantly, sites with E1-E2 elements showed tighter phases both in binding and mRNA accumulation. Finally, comparing the temporal accumulation of precursor mRNA and mature mRNA helped distinguish direct BMAL1 targets from targets with more complex regulation, and showed how transcriptional and post-transcriptional regulation contribute differentially to circadian expression phase. Together, our analysis of a dynamic protein-DNA interactome uncovered how genes of the core circadian oscillator are wired together and drive phase-specific circadian output programs in a complex tissue.