TORC1 is a structurally and functionally conserved multiprotein complex that regulates many aspects of eukaryote growth including the synthesis and assembly of ribosomes. The protein kinase activity of this complex is responsive to environmental cues and is potently inhibited by the natural product macrolide rapamycin. Insights into how TORC1 regulates growth have been provided with the recent identification of the rapamycin-sensitive phosphoproteome in yeast. Building on these data, we show here that Sch9, an AGC family kinase and direct substrate of TORC1, promotes ribosome biogenesis (ribi) and ribosomal protein (RP) gene expression via direct inhibitory phosphorylation of three transcription repressors, Stb3, Dot6 and Tod6. Dephosphorylation of these factors allows them to recruit the RPD3L histone deactelyase complex to ribi/RP gene promoters. Since rRNA and tRNA transcription are also under its control, Sch9 appears to be well positioned to coordinately regulate transcriptional aspects of ribosome biogenesis. Overall design: mRNA-Seq of 8 S. cerevisiae strains treated with either DMSO alone or 1NM-PP1, a small molecule inhibitor for analog-sensitive kinases such as sch9-as.
Sch9 regulates ribosome biogenesis via Stb3, Dot6 and Tod6 and the histone deacetylase complex RPD3L.
Specimen part, Cell line, Treatment, Subject
View SamplesDouble-stranded RNA-binding proteins are key elements in the intracellular localization of mRNA and its local translation. Staufen is a double-stranded RNA binding protein involved in the localised translation of specific mRNAs during Drosophila early development and neuronal cell fate. The human homologue Staufen1 forms RNA-containing complexes that include proteins involved in translation and motor proteins to allow their movement within the cell, but the mechanism underlying translation repression in these complexes is poorly understood. Here we show that human Staufen1-containing complexes contain essential elements of the gene silencing apparatus, like Ago1-3 proteins, and we describe a set of miRNAs specifically associated to complexes containing human Staufen1. Among these, miR124 stands out as particularly relevant because it appears enriched in human Staufen1 complexes and is over-expressed upon differentiation of human neuroblastoma cells in vitro. In agreement with these findings, we show that expression of human Staufen1 is essential for proper dendritic arborisation during neuroblastoma cell differentiation, yet it is not necessary for maintenance of the differentiated state, and suggest potential human Staufen1 mRNA targets involved in this process.
Human Staufen1 associates to miRNAs involved in neuronal cell differentiation and is required for correct dendritic formation.
Cell line
View SamplesThis study is part of previous epidemiologic project, including a population-based survey (Sao Paulo Ageing & Health study (SPAH Study). The data from this study was collected between 2015 to 2016 and involved elderly women (ages ≥65 yeas) living in the Butanta district, Sao Paulo. The purpose of the study was identification of association between transcriptome and the osteo metabolism diseases phenotype, like osteoporosis, vertebral fracture and coronary calcification.
Overexpression of SNTG2, TRAF3IP2, and ITGA6 transcripts is associated with osteoporotic vertebral fracture in elderly women from community.
Sex, Age
View SamplesDespite the well-established role of the frontal and posterior peri-sylvian cortices in many facets of human-cognitive specializations, including language, little is known about the developmental patterning of these regions in human brain. We performed a genome-wide analysis of human cerebral patterning during mid-gestation, a critical epoch in cortical regionalization. A total of 345 genes were identified as differentially expressed (DE) between superior temporal gyrus (STG) and the remaining cerebral cortex (CTX). GO categories representing transcription factors were enriched in STG, while cell-adhesion and extracellular matrix molecules, were enriched in the other cortical regions. Q-PCR or in situ hybridization were performed to validate differential expression in a subset of 32 genes, most of which were confirmed. LIM domain binding 1 (LDB1), which we show to be enriched in the STG, is a recently identified interactor of LIM domain only 4 (LMO4), a gene known to be involved in the asymmetric pattering of the peri-sylvian region in the developing human brain. Protocadherin 17 (PCDH17), a neuronal cell adhesion molecule, was highly enriched in focal regions of the human prefrontal cortex. Contactin Associated Protein-Like 2 (CNTNAP2), in which mutations are known to cause autism, epilepsy and language delay, showed a remarkable pattern of anterior enriched expression in cortical regions important for human higher cognition. Importantly, a similar pattern was not observed in the mouse or rat. These data highlight the importance of expression analysis of human brain and the utility of cross-species comparisons of gene expression. Genes identified here provide a foundation for understanding molecular aspects of human-cognitive specializations and disorders that disrupt them.
Genome-wide analyses of human perisylvian cerebral cortical patterning.
Sex, Age
View SamplesProtein synthesis belongs to the most energy consuming processes in the cell. Lowering oxygen tension below normal (hypoxia) causes a rapid inhibition of global mRNA translation due to the decreased availability of energy. Interestingly, subsets of mRNAs pursue active translation under such circumstances. In human fibrosarcoma cells (HT1080) exposed to prolonged hypoxia (36 h, 1% oxygen) we observed that transcripts are either increasingly or decreasingly associated with ribosomes localized at the endoplasmic reticulum (ER). In a global setting it turned out that only 31% of transcripts showing elevated total-RNA levels were also increasingly present at the ER in hypoxia. These genes, regulated by its expression as well as its ER-localization, belong to the gene ontologys hypoxia response, glycolysis and HIF-1 transcription factor network supporting the view of active mRNA translation at the ER during hypoxia. Interestingly, a large group of RNAs was found to be unchanged at the expression level, but translocate to the ER in hypoxia. Among these are transcripts encoding translation factors and >180 ncRNAs. In summary, we provide evidence that protein synthesis is favoured at the ER and, thus, partitioning of the transcriptome between cytoplasmic and ER associated ribosomes mediates adaptation of gene expression in hypoxia.
Hypoxia-induced gene expression results from selective mRNA partitioning to the endoplasmic reticulum.
Specimen part, Cell line
View SamplesMitogen activated protein kinase (MAPK) signaling regulates differentiation of many cell types. During myogenesis in particular, p38a MAPK (MAPK14) phosphorylates multiple transcriptional regulators to modulate muscle-specific gene expression. Among the p38a MAPK modulated genes is the muscle-specific transcriptional regulator Myogenin (Myog) that is also essential to complete the muscle differentiation program, and while it is known that both p38a MAPK and Myog are critically required for myogenesis, the individual contribution of each of these proteins is poorly defined. Here we show that Myog expression (in the absence of p38a MAPK signaling) is sufficient to establish expression of many late markers of muscle differentiation and to mediate cell migration. However, Myog expression alone did not led to the formation of multinucleated muscle cells, highlighting a critical role for p38a MAPK in myoblast fusion. Using comparative microarray analysis we identified p38a MAPK-dependent genes that are not regulated by Myog
Comparative expression profiling identifies differential roles for Myogenin and p38α MAPK signaling in myogenesis.
Cell line
View SamplesE2 exposure significantly decreased peak viral titer in hNECs from female donors. We used microarray analyses to identify global gene expression patterns between E2 and vehicle exposed hNECs from female donors
Estrogenic compounds reduce influenza A virus replication in primary human nasal epithelial cells derived from female, but not male, donors.
Sex, Specimen part, Treatment
View SamplesStem cell development requires selection of specific genetic programs to direct cellular fate. Using microarray technology, we profile expression trends at selected timepoints during stem cell differentiation to characterize these changes.
Genomic chart guiding embryonic stem cell cardiopoiesis.
Specimen part
View SamplesPlant drought stress response and resistance are complex biological processes that merit systems-level analyses to dissect drought stress encountered by crops in the field. We have used gene expression profiling of Arabidopsis plants subjected to a controlled, sublethal, moderate drought (mDr) treatment to characterize early and late response to drought. We have also compared these profiles to those from plants treated with soil water deficit (progressive) drought (pDr) to reveal acclimation responses in plants.
Molecular and physiological analysis of drought stress in Arabidopsis reveals early responses leading to acclimation in plant growth.
Specimen part, Treatment
View SamplesInadequate extracellular conditions can adversely affect the environment of the ER and impinge on the maturation of nascent proteins. The resultant accumulation of unfolded proteins activates a signal transduction pathway, known as the unfolded protein response, which serves primarily to protect the cell during stress and helps restore homeostasis to the ER. Microarray analysis of the unfolded protein response in a human medulloblastoma cell line treated with thapsigargin revealed that, in addition to known targets, a large number of proangiogenic factors were up-regulated. Real-time PCR analyses confirmed that four of these factors, VEGF, FGF2, angiogenin and IL-8, were transcriptionally up-regulated in multiple cell lines by various ER stress inducers. Our studies on VEGF regulation revealed that XBP-1(S), a UPR-inducible transcription factor, bound to two regions on the VEGF promoter, and analysis of XBP-1 null mouse embryonic fibroblasts revealed that it contributes to VEGF expression in response to ER stress. ATF4, another UPR-inducible transcription factor, also binds to the VEGF gene, although its contribution to VEGF transcription appeared to be fairly modest. We also found that VEGF mRNA stability is increased in response to UPR activation, via activation of the AMP and p38MAP kinases, demonstrating that increased mRNA levels occur at two regulatory points. In keeping with the mRNA levels, we found that VEGF protein is secreted at levels as high as or higher than that achieved in response to hypoxia. Our results indicate that the UPR plays a significant role in inducing positive regulators of angiogenesis. It also regulates VEGF expression at multiple levels and is likely to have widespread implications for promoting angiogenesis in response to normal physiological cues as well as in pathological conditions like cancer.
Transcriptional and post-transcriptional regulation of proangiogenic factors by the unfolded protein response.
Treatment, Time
View Samples