Project description:In the preimplantation mouse embryo TEAD4 is critical to establishing the trophectoderm (TE)-specific transcriptional program and segregating TE from the inner cell mass (ICM). However, TEAD4 is expressed both in the TE and the ICM. Thus, differential function of TEAD4 rather than expression itself regulates specification of the first two cell lineages. We used ChIP-seq to define genome-wide TEAD4 target genes and asked how transcription of TEAD4 target genes is specifically maintained in the TE. Our analyses revealed an evolutionarily conserved mechanism, in which lack of nuclear localization of TEAD4 impairs the TE-specific transcriptional program in inner blastomeres, thereby allowing their maturation towards the ICM lineage. Restoration of TEAD4 nuclear localization maintains the TE-specific transcriptional program in the inner blastomeres and prevents segregation of the TE and ICM lineages and blastocyst formation. We propose that altered subcellular localization of TEAD4 in blastomeres dictates first mammalian cell fate specification. ChIPseq profiles of TEAD4, IgG, Input in Mouse trophoblast stem cells using Illumina HiSeq 2000 and Illumina Genome Analyzer IIx
Project description:The distribution of RNA in human embryonic stem cells (hESC) and the function of RNA localization in maintaining hESC pluripotency and differentiation are currently unknown. Here, by isolating five subcellular components of hESCs and differentiated cells, we uncovered the global subcellular RNA localization in hESC. For protein-coding mRNA, different transcripts of the same gene exhibit an “isoform switch” between subcellular components, which is regulated by localization cis-elements in their variable regions. For noncoding RNA, multiple sequence features such as polyA tail, length, and GC content jointly regulate their subcellular localization. In addition, we found that some developmental genes can be transcribed in advance and confined to chromatin in undifferentiated hESCs. Finally, we revealed significant changes in overall RNA distribution, mapped RNA dynamic localization atlas, and characterized different dynamic RNA localization patterns during hESC differentiation into mesoderm. The multiple RNA localization patterns we revealed will provide some new enlightenment for hESC stemness maintenance and differentiation.
Project description:In the preimplantation mouse embryo TEAD4 is critical to establishing the trophectoderm (TE)-specific transcriptional program and segregating TE from the inner cell mass (ICM). However, TEAD4 is expressed both in the TE and the ICM. Thus, differential function of TEAD4 rather than expression itself regulates specification of the first two cell lineages. We used ChIP-seq to define genome-wide TEAD4 target genes and asked how transcription of TEAD4 target genes is specifically maintained in the TE. Our analyses revealed an evolutionarily conserved mechanism, in which lack of nuclear localization of TEAD4 impairs the TE-specific transcriptional program in inner blastomeres, thereby allowing their maturation towards the ICM lineage. Restoration of TEAD4 nuclear localization maintains the TE-specific transcriptional program in the inner blastomeres and prevents segregation of the TE and ICM lineages and blastocyst formation. We propose that altered subcellular localization of TEAD4 in blastomeres dictates first mammalian cell fate specification.
Project description:Precise, area-specific connectivity of interhemispheric callosal projection neurons (CPN) in the cerebral cortex is critical for sensory, associative, and behavioral functions. CPN circuitry, which connects and integrates the two cerebral hemispheres via the corpus callosum, is centrally implicated in autism spectrum disorder (ASD) and intellectual disability (ID). Though transcriptional controls regulating CPN subtype and areal development have progressively become partially understood, downstream subcellular mechanisms and molecular machinery that implement precise and diverse CPN circuitry is essentially unknown. Here, we identify that the highly penetrant ASD/ID risk gene Bcl11a/Ctip1 is critical developmentally for appropriate and precise areal targeting of CPN associative projections, and that its deletion both strikingly reshapes these projections, and causes dramatic disruption to circuit-specific subcellular growth cone (GC) molecular machinery and social behavior and cognition in mice. CPN-specific embryonic deletion of Bcl11a causes loss of correct homotopic targeting in the contralateral cortex, re-routes a substantial proportion of their axonal projections through the evolutionarily older anterior commissure, and induces strikingly aberrant, but specific and precise, projections to the basolateral amygdala in adult mice. Importantly, bilateral deletion of Bcl11a from CPN alone results in abnormal social behavior and working memory. Mechanistically, we identify dysregulation of the CPN axonal GC-localized transcriptome in Bcl11a nulls, due to either aberrant transcription or trafficking of individual transcripts. These molecular mis-localizations disrupt axon guidance and CPN-specific associative circuitry formation, causing disease-related behavior. Together, this work identifies critical functions for Bcl11a in CPN axonal connectivity, development of functional associative-social circuitry, regulation of subtype-specific subcellular molecular machinery in vivo, revealing novel GC-localized transcripts that regulate precise axonal targeting and circuit formation. These results elucidate development and ASD/ID disease-related circuit disruption of CPN, and the importance of understanding circuit-specific subcellular– e.g. soma vs. GC– localization of RNA and protein molecular machinery by neurons.
Project description:Objective: To assess the role of aldoketoreductases and other doxorubicin pharmacokinetic or pharmacogenomic genes in doxorubicin cytotoxicity, resistance, DNA binding activity, and subcellular localization, Methods: We conducted a whole genome microarray study to identify differences in between doxorubicin-sensitive MCF-7cc cells and doxorubicin-resistant MCF-7Dox2-12 cells in terms of their expression of genes related to doxorubicin pharmacokinetics or pharmacodynamics. Targets were then validated by pharmacologic inhibition in conjunction with drug metabolite profiling, drug localization, drug cytotoxicity, and drug DNA binding studies. Results: 2063 differentially expressed transcripts were identified, including 17% and 43% of genes or gene families associated with doxorubicin pharmacokinetics or pharmacodynamics (p values of significance of 0.05 and <0.0001, respectively). The largest changes in the expression of genes associated with doxorubicin pharmacokinetics and pharmacodynamics were chiefly among the aldo-keto reductases (AKRs) Akr1c2, Akr1c3 and Akr1b10 which convert doxorubicin to doxorubicinol. We observed that doxorubicinol exhibits dramatically reduced drug toxicity, reduced drug DNA-binding activity, and altered drug subcellular localization to lysosomes. Pharmacologic inhibition of these AKRs in MCF-7Dox2-12 cells restored drug cytotoxicity, and drug localization to the nucleus. Conclusion: These findings demonstrate the utility of using curated pharmacokinetic and pharmacodynamic knowledgebases to identify highly relevant genes associated with doxorubicin resistance. The products of one or more of these genes could effectively be shown to alter the drug’s properties, while inhibiting them restored drug DNA binding, cytotoxicity, and subcellular localization. Doxorubicin resistant cell lines of breast MCF-7 cells were generated for gene expression profilling. Two colour microarray of Agilent whole human genome nucleotide arrays was conducted with four labelling replicates of both forward and reverse labellings plus another set of 8 arrays with forward labelling. Sixteen arrays were used for this experiments. The co-cultured control cells MCF-7cc12 was generated by parallel selection process in the absence of drug.
Project description:Defining the subcellular distribution of all human proteins and its remodeling across cellular states remains a central goal in cell biology. Here, we present a high-resolution strategy to map subcellular organization using organelle immuno-capture coupled to mass spectrometry. We apply this workflow to a cell-wide collection of membranous and membrane-less compartments. A graph-based analysis reveals the subcellular localization of over 7,600 proteins, defines spatial networks, and uncovers interconnections between cellular compartments. Our approach can be deployed to comprehensively profile proteome remodeling during cellular perturbation. By characterizing the cellular landscape following hCoV-OC43 viral infection, we discover that many proteins are regulated by changes in their spatial distribution rather than by changes in abundance. Our results establish that proteome-wide analysis of subcellular remodeling provides unique insights for the elucidation of cellular responses, uncovering an essential role for ferroptosis in OC43 infection. Our dataset can be explored at organelles.czbiohub.org.
Project description:To elucidate the role of HNRNPU in regulation of lncRNAs nuclear localization, we knocked down HNRNPU in K562 cells using short interfering RNAs and performed subcellular RNA-seq using nuclear or cytosolic RNAs