This SuperSeries is composed of the SubSeries listed below.
The Sexual Dimorphism of Dietary Restriction Responsiveness in Caenorhabditis elegans.
Sex, Specimen part, Treatment
View SamplesCholesterol has attracted significant attention as a possible lifespan regulator. It has been reported that serum cholesterol levels have an impact on mortality due to age-related disorders such as cardiovascular disease. Diet is also known to be an important lifespan regulator. Dietary restriction retards the onset of age-related diseases and extends lifespan in various organisms. Although cholesterol and dietary restriction are known to be lifespan regulators, it remains to be established whether cholesterol is involved in dietary restriction-induced longevity. Here, we show that cholesterol deprivation suppresses longevity induced by intermittent fasting, which is one of the dietary restriction regimens that effectively extend lifespan. We also found that cholesterol is required for the fasting-induced upregulation of transcriptional target genes such as the insulin/IGF-1 pathway effector DAF-16 and that cholesterol deprivation suppresses the long lifespan of the insulin/IGF-1 receptor daf-2 mutant. Remarkably, we found that cholesterol plays an important role in the fasting-induced nuclear accumulation of DAF-16. Moreover, knockdown of the cholesterol-binding protein NSBP-1, which has been shown to bind to DAF-16 in a cholesterol-dependent manner and to regulate DAF-16 activity, suppresses both fasting-induced longevity and DAF-16 nuclear accumulation. Furthermore, this suppression was not additive to the cholesterol deprivation-induced suppression, which suggests that NSBP-1 mediates, at least in part, the action of cholesterol to promote fasting-induced longevity and DAF-16 nuclear accumulation. These findings identify a novel role for cholesterol in the regulation of lifespan.
Cholesterol regulates DAF-16 nuclear localization and fasting-induced longevity in C. elegans.
No sample metadata fields
View SamplesMany species undergo sexual reproduction to distribute the parental genomes and increase the genomic diversity of the progeny. Among such species, sexual dimorphism is often displayed through morphology, size, behavior, and life-span, depending on the survival and reproduction strategies of the species. The nematode Caenorhabditis elegans has two sexes, hermaphrodite and male, and only the hermaphrodites, which produce both oocytes and sperm, are essential for the perpetuation of the species. In this study, we found that dietary restriction, which is the most reproducible way to retard aging in many species, extends the life-span of C. elegans hermaphrodites but not that of males. Our analysis revealed that fasting induces male-enriched genes in hermaphrodites and that the sex determination pathway affects life-span regulation, even after the completion of development, and is regulated by food availability. Furthermore, fasting activates the entire X-chromosome only in hermaphrodites. Our tiling array analysis identified a fasting-inducible, X-linked non-coding RNA for which expression positively correlated with the activation level of the X-chromosome and longevity. These links between the sex determination mechanism and dietary restriction at multiple levels may give priority to the survival of hermaphrodites during food shortages in C. elegans.
The Sexual Dimorphism of Dietary Restriction Responsiveness in Caenorhabditis elegans.
No sample metadata fields
View SamplesWe performed expression profiling of 36 types of normal human tissues and identified 2,503 tissue-specific genes. We then systematically studied the expression of these genes in cancers by re-analyzing a large collection of published DNA microarray datasets. Our study shows that integration of each gene's breadth of expression (BOE) in normal tissues is important for biological interpretation of the expression profiles of cancers in terms of tumor differentiation, cell lineage and metastasis.
Interpreting expression profiles of cancers by genome-wide survey of breadth of expression in normal tissues.
No sample metadata fields
View SamplesTo achieve the extreme nuclear condensation necessary for sperm function, most histones are replaced with protamines during spermiogenesis in mammals. Mature sperm retain only a small fraction of nucleosomes, which are, in part, enriched on gene regulatory sequences, and recent findings suggest that these retained histones provide epigenetic information that regulates expression of a subset of genes involved in embryo development after fertilization. We addressed this tantalizing hypothesis by analyzing two mouse models exhibiting abnormal histone positioning in mature sperm due to impaired poly(ADP-ribose) (PAR) metabolism during spermiogenesis and identified altered sperm histone retention in specific gene loci genome-wide using MNase digestion-based enrichment of mononucleosomal DNA. We then set out to determine the extent to which expression of these genes was altered in embryos generated with these sperm. For control sperm, most genes showed some degree of histone association, unexpectedly suggesting that histone retention in sperm genes is not an all-or-none phenomenon and that a small number of histones may remain associated with genes throughout the genome. The amount of retained histones, however, was altered in many loci when PAR metabolism was impaired. To ascertain whether sperm histone association and embryonic gene expression are linked, the transcriptome of individual 2-cell embryos derived from such sperm was determined using microarrays and RNA sequencing. Strikingly, a moderate but statistically significant portion of the genes that were differentially expressed in these embryos also showed different histone retention in the corresponding gene loci in sperm of their fathers. These findings provide new evidence for the existence of a linkage between sperm histone retention and gene expression in the embryo. Overall design: 9 WT samples in 3 groups of 3. Each group consists of 3 eggs fertilized by the same father. 9 KO samples in the same setup.
Paternal poly (ADP-ribose) metabolism modulates retention of inheritable sperm histones and early embryonic gene expression.
No sample metadata fields
View SamplesHepatocyte nuclear factor-4 (HNF4, NR2A1) is a nuclear receptor which has a critical role in hepatocyte differentiation and the maintenance of homeostasis in the adult liver. However, a detailed understanding of native HNF4 in the steady state remains to be elucidated. Here we report the native HNF4 isoforms, phosphorylation status and complexes in the steady state, as shown by shotgun proteomics in HepG2 hepatocarcinoma cells. Shotgun proteomic analysis revealed the complexity of native HNF4, including multiple phosphorylation sites and inter-isoform heterodimerization. The associating complexes identified by label-free semi-quantitative proteomic analysis include the following: the DNA-dependent protein kinase catalytic subunit, histone acetyltransferase complexes, mRNA splicing complex, other nuclear receptor coactivator complexes, the chromatin remodeling complex, and the nucleosome remodeling and histone deacetylation complex. Among the associating proteins, GRB10 interacting GYF protein 2 (GIGYF2, PERQ2) is a new candidate cofactor in metabolic regulation. Moreover, an unexpected heterodimerization of HNF4 and Hepatocyte nuclear factor-4 was found. A biochemical and genome-wide analysis of transcriptional regulation showed that this heterodimerization activates gene transcription. The genes thus transcribed include the cell death-inducing DEF45-like effector b (CIDEB) gene, which is an important regulator of lipid metabolism in the liver. This suggests that the analysis of the distinctive stoichiometric balance of native HNF4 and its cofactor complexes described here is important for an accurate understanding of transcriptional regulation.
Proteomic analysis of native hepatocyte nuclear factor-4α (HNF4α) isoforms, phosphorylation status, and interactive cofactors.
Specimen part, Cell line
View SamplesHepatocyte nuclear factor-4 (HNF4, NR2A1) is a nuclear receptor which has a critical role in hepatocyte differentiation and the maintenance of homeostasis in the adult liver. However, a detailed understanding of native HNF4 in the steady state remains to be elucidated. Here we report the native HNF4 isoforms, phosphorylation status and complexes in the steady state, as shown by shotgun proteomics in HepG2 hepatocarcinoma cells. Shotgun proteomic analysis revealed the complexity of native HNF4, including multiple phosphorylation sites and inter-isoform heterodimerization. The associating complexes identified by label-free semi-quantitative proteomic analysis include the following: the DNA-dependent protein kinase catalytic subunit, histone acetyltransferase complexes, mRNA splicing complex, other nuclear receptor coactivator complexes, the chromatin remodeling complex, and the nucleosome remodeling and histone deacetylation complex. Among the associating proteins, GRB10 interacting GYF protein 2 (GIGYF2, PERQ2) is a new candidate cofactor in metabolic regulation. Moreover, an unexpected heterodimerization of HNF4 and Hepatocyte nuclear factor-4 was found. A biochemical and genome-wide analysis of transcriptional regulation showed that this heterodimerization activates gene transcription. The genes thus transcribed include the cell death-inducing DEF45-like effector b (CIDEB) gene, which is an important regulator of lipid metabolism in the liver. This suggests that the analysis of the distinctive stoichiometric balance of native HNF4 and its cofactor complexes described here is important for an accurate understanding of transcriptional regulation.
Proteomic analysis of native hepatocyte nuclear factor-4α (HNF4α) isoforms, phosphorylation status, and interactive cofactors.
Specimen part, Cell line
View SamplesThe differentiation of preadipocytes into adipocytes is controlled by several transcription factors, including peroxisome proliferator-activated receptor (PPAR) and CCAAT/enhancer-binding protein (C/EBP), which are known as master regulators of adipogenesis. BCL11B is a zinc finger-type transcription factor that regulates the development of the skin and central nervous and immune systems. Here, we found that BCL11B was expressed in the white adipose tissue (WAT), particularly the subcutaneous WAT and that BCL11B/ mice had a reduced amount of subcutaneous WAT. During adipogenesis, BCL11B expression transiently increased in 3T3-L1 preadipocytes and mouse embryonic fibroblasts (MEFs). The ability for adipogenesis was reduced in BCL11B knockdown 3T3-L1 cells and BCL11B/ MEFs, whereas the ability for osteoblastogenesis was unaffected in BCL11B/ MEFs. Luciferase reporter gene assays revealed that BCL11B stimulated C/EBP activity. Furthermore, the expression of downstream genes of the Wnt/-catenin signaling pathway was not suppressed in BCL11B/ MEFs during adipogenesis. Thus, this study identifies BCL11B as a novel regulator of adipogenesis, which works, at least in part, by stimulating C/EBP activity and suppressing the Wnt/-catenin signaling pathway.
Identification of BCL11B as a regulator of adipogenesis.
Specimen part
View SamplesGATA2 is well recognized as a key transcription factor and regulator of cell type specificity and differentiation. Here, we carried out comparative chromatin immunoprecipitation with comprehensive sequencing (ChIP-seq) to determine genome-wide occupancy of GATA2 in endothelial cells and erythroids, and compared the occupancy to the respective gene expression profile in each cell type. Although GATA2 was commonly expressed in both cell types, different GATA2 bindings and distinct cell specific gene expressions were observed. By using the ChIP-seq with epigenetic histone modifications and chromatin conformation capture assays; we elucidated the mechanistic regulation of endothelial-specific GATA2 mediated endomucin gene expression, that was regulated by the endothelial-specific chromatin loop with a GATA2 associated distal enhancer and core promoter. Knockdown of endomucin markedly attenuated endothelial cell growth, migration and tube formation. Moreover, abrogation of GATA2 in endothelium demonstrated not only a reduction of endothelial specific markers, but also induction of mesenchymal transition promoting gene expression. Our findings provide new insights into the correlation of endothelial expressed GATA2 binding, epigenetic modification, and the determination of endothelial cell specificity.
Epigenetically coordinated GATA2 binding is necessary for endothelium-specific endomucin expression.
No sample metadata fields
View SamplesTranscriptome analysis of post-mortem brain tissue specimens from three brain regions (BRs), entorinal, temporal and frontal cortices, of 71 Japanese brain-donor subjects to identify genes relevant to the expansion of neurofibrillary tangles. In total, 213 brain tissue specimens (= 71 subjects 3 BRs) were involved in this study. The spreading of neurofibrillary tangles (NFTs), intraneuronal aggregates of highly phosphorylated microtubule-associated protein tau, across the human brain is correlated with the cognitive severity of Alzheimers disease (AD). To identify genes relevant to NFT expansion defined by the Braak stage, we conducted exon array analysis with an exploratory sample set consisting of 213 human post-mortem brain tissue specimens from the entorinal, temporal and frontal cortices of 71 brain-donor subjects: Braak NFT stages 0 (N = 13), III (N = 20), IIIIV (N = 19) and VVI (N = 19). We identified eight genes, RELN, PTGS2, MYO5C, TRIL, DCHS2, GRB14, NPAS4 and PHYHD1, associated with the Braak stage. The expression levels of three genes, PHYHD1, MYO5C and GRB14, exhibited reproducible association on real-time quantitative PCR analysis. In another sample set, including control subjects (N = 30) and patients with late-onset AD (N = 37), dementia with Lewy bodies (N = 17) and Parkinson disease (N = 36), the expression levels of two genes, PHYHD1 and MYO5C, were obviously associated with late-onset AD. Proteinprotein interaction network analysis with a public database revealed that PHYHD1 interacts with MYO5C via POT1, and PHYHD1 directly interacts with amyloid beta-peptide 42. It is thus likely that functional failure of PHYHD1 and MYO5C could lead to AD development.
Genes associated with the progression of neurofibrillary tangles in Alzheimer's disease.
Sex, Specimen part, Subject
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