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Hidemasa Bono

Publications and source records attributed to Hidemasa Bono.

At least 19 recordsLinked to original sources
PubMed2005

The study of metabolic pathways in tumors based on the transcriptome.

DNA microarray technology revolutionized gene-expression analysis in molecular biology to observe patterns of gene expression in genomic scale. We review the biological aspects of genome-wide gene-expression activity in tumors specially focusing on the analysis of enzyme coding genes. First, the methods for analyzing gene-expression data for the study of metabolome in silico are discussed showing SV40T antigen expressing liver tumor data as an example. Next, an application for tumor metabolome analysis utilizing a reference set of gene-expression profiles is shown.

Animals↗
PubMed2004

Identification and functional analysis of consensus androgen response elements in human prostate cancer cells.

Androgen receptor (AR) recognizes and binds to 15-bp palindromic androgen response element (ARE) sequences with high affinity in vitro, which consist of two hexameric half-sites arranged as inverted repeats with a 3-bp spacer. Although a few near-consensus ARE sequences have been actually identified in the transcriptional regulatory regions of androgen-responsive genes, it has been unclear whether the exact consensus sequences function as bona fide AREs in vivo. A genome-wide in silico screening of palindromic AREs identified 563 exact consensus sequences in the human genome. The distribution of perfect palindromic AREs among the chromosomes is basically consistent with the length of chromosomes. Using human prostate cancer cell line LNCaP treated with a synthetic androgen R1881 as a model, in vivo AR binding abilities of 21 consensus AREs were analyzed by chromatin immunoprecipitation. Of 21 genomic fragments containing perfect AREs in chromosome X, 8 fragments recruited more ARs (>4-fold enrichment) even compared with the proximal ARE region of prostate-specific antigen. A couple of proximal genes or putative transcripts in the vicinity of the perfect AREs were found to be androgen-responsive analyzed by quantitative RT-PCR. Our results suggest that some of perfect palindromic AREs could function as in vivo AR binding sites in the human genome and regulate gene transcription.

Androgens↗
PubMed2004

Integrative annotation of 21,037 human genes validated by full-length cDNA clones.

The human genome sequence defines our inherent biological potential; the realization of the biology encoded therein requires knowledge of the function of each gene. Currently, our knowledge in this area is still limited. Several lines of investigation have been used to elucidate the structure and function of the genes in the human genome. Even so, gene prediction remains a difficult task, as the varieties of transcripts of a gene may vary to a great extent. We thus performed an exhaustive integrative characterization of 41,118 full-length cDNAs that capture the gene transcripts as complete functional cassettes, providing an unequivocal report of structural and functional diversity at the gene level. Our international collaboration has validated 21,037 human gene candidates by analysis of high-quality full-length cDNA clones through curation using unified criteria. This led to the identification of 5,155 new gene candidates. It also manifested the most reliable way to control the quality of the cDNA clones. We have developed a human gene database, called the H-Invitational Database (H-InvDB; http://www.h-invitational.jp/). It provides the following: integrative annotation of human genes, description of gene structures, details of novel alternative splicing isoforms, non-protein-coding RNAs, functional domains, subcellular localizations, metabolic pathways, predictions of protein three-dimensional structure, mapping of known single nucleotide polymorphisms (SNPs), identification of polymorphic microsatellite repeats within human genes, and comparative results with mouse full-length cDNAs. The H-InvDB analysis has shown that up to 4% of the human genome sequence (National Center for Biotechnology Information build 34 assembly) may contain misassembled or missing regions. We found that 6.5% of the human gene candidates (1,377 loci) did not have a good protein-coding open reading frame, of which 296 loci are strong candidates for non-protein-coding RNA genes. In addition, among 72,027 uniquely mapped SNPs and insertions/deletions localized within human genes, 13,215 nonsynonymous SNPs, 315 nonsense SNPs, and 452 indels occurred in coding regions. Together with 25 polymorphic microsatellite repeats present in coding regions, they may alter protein structure, causing phenotypic effects or resulting in disease. The H-InvDB platform represents a substantial contribution to resources needed for the exploration of human biology and pathology.

Alternative Splicing↗
PubMed2004

Gene discovery in genetically labeled single dopaminergic neurons of the retina.

In the retina, dopamine plays a central role in neural adaptation to light. Progress in the study of dopaminergic amacrine (DA) cells has been limited because they are very few (450 in each mouse retina, 0.005% of retinal neurons). Here, we applied transgenic technology, single-cell global mRNA amplification, and cDNA microarray screening to identify transcripts present in DA cells. To profile gene expression in single neurons, we developed a method (SMART7) that combines a PCR-based initial step (switching mechanism at the 5' end of the RNA transcript or SMART) with T7 RNA polymerase amplification. Single-cell targets were synthesized from genetically labeled DA cells to screen the RIKEN 19k mouse cDNA microarrays. Seven hundred ninety-five transcripts were identified in DA cells at a high level of confidence, and expression of the most interesting genes was confirmed by immunocytochemistry. Twenty-one previously undescribed proteins were found in DA cells, including a chloride channel, receptors and other membrane glycoproteins, kinases, transcription factors, and secreted neuroactive molecules. Thirty-eight percent of transcripts were ESTs or coding for hypothetical proteins, suggesting that a large portion of the DA cell proteome is still uncharacterized. Because cryptochrome-1 mRNA was found in DA cells, immunocytochemistry was extended to other components of the circadian clock machinery. This analysis showed that DA cells contain the most common clock-related proteins.

Animals↗
PubMed2004

Identification of unique transcripts from a mouse full-length, subtracted inner ear cDNA library.

A small-scale full-length library construction approach was developed to facilitate production of a mouse full-length cDNA encyclopedia representing approximately 250 enriched, normalized, and/or subtracted cDNA libraries. One library produced using this approach was a subtracted adult mouse inner ear cDNA library (sIEa). The average size of the inserts was approximately 2.5 kb, with the majority ranging from 0.5 to 7.0 kb. From this library 22,574 sequence reads were obtained from 15,958 independent clones. Sequencing and chromosomal localization established 5240 clusters, with 1302 clusters being unique and 359 representing new ESTs. Our sIEa library contributed 56.1% of the 7773 nonredundant Unigene clusters associated with the four mouse inner ear libraries in the NCBI dbEST. Based on homologous chromosomal regions between human and mouse, we identified 1018 UniGene clusters associated with the deafness locus critical regions. Of these, 59 clusters were found only in our sIEa library and represented approximately 50% of the identified critical regions.

Amino Acid Sequence↗
PubMed2003

MaXML: mouse annotation XML.

Although the sequencing of the human genome and several model organisms is almost complete, the number of genes in the human is still in debate. cDNA (complementary DNA) is generated from mRNA that is transcribed from the genome and can be regarded as a gene itself; therefore, decoding cDNA sequences is important in characterizing genes. Recently, biologists have been able to describe more knowledge about genes in order to characterize them, and this information is generally called 'annotation.' Furthermore, annotation is important in understanding the systems of organisms in various fields of research. We therefore constructed the MaXML (Mouse annotation XML) format with which mouse cDNA annotation data can be exchanged and shared between laboratories more efficiently. Defining strict data types for annotations is difficult, but we consider XML a feasible format for describing them. We have used the MaXML format to express mouse annotation data in FANTOM DB. We have also developed tools and systems utilizing these MaXML data, including a parser and a server to provide data on-the-fly.

Animals↗
PubMed2003

Molecular basis of constitutive production of basement membrane components. Gene expression profiles of Engelbreth-Holm-Swarm tumor and F9 embryonal carcinoma cells.

Engelbreth-Holm-Swarm (EHS) tumors produce large amounts of basement membrane (BM) components that are widely used as cell culture substrates mimicking BM functions. To delineate the tissue/organ origin of the tumor and the mechanisms operating in the BM overproduction, a genome-wide expression profile of EHS tumor was analyzed using RIKEN cDNA microarrays containing approximately 40,000 mouse cDNA clones. Expression profiles of F9 embryonal carcinoma cells that produce laminin-1 and other BM components upon differentiation into parietal endoderm-like cells (designated F9-PE) were also analyzed. Hierarchical clustering analysis showed that the gene expression profiles of EHS and F9-PE were the most similar among 49 mouse tissues/organs in the RIKEN Expression Array Database, suggesting that EHS tumor is parietal endoderm-derived. Quantitative PCR analysis confirmed that not only BM components but also the machineries required for efficient production of BM components, such as enzymes involved in post-translational modification and molecular chaperones, were highly expressed in both EHS and F9-PE. Pairs of similar transcription factor isoforms, such as Gata4/Gata6, Sox7/Sox17, and Cited1/Cited2, were also highly expressed in both EHS tumor and F9-PE. Time course analysis of F9 differentiation showed that up-regulation of the transcription factors was associated with those of BM components, suggesting their involvement in parietal endoderm specification and overproduction of the BM components.

Animals↗
PubMed2003

Gene expression profile of normal lungs predicts genetic predisposition to lung cancer in mice.

Genetic susceptibility to lung tumorigenesis shows large variations among mouse strains. To test whether genetic predisposition to lung tumorigenesis is associated with a specific gene expression profile in normal lungs, we analyzed gene expression in 16 inbred strains of known susceptibility/resistance to lung tumorigenesis, using the RIKEN mouse full-length cDNA 19K microarray set. The strain-specific expression profile of 91 cDNA clones correlated with strain lung tumor susceptibility/resistance and predicted, by principal component analysis, the genetic predisposition to lung tumorigenesis in mice.

Animals↗
PubMed2003

Detection of genes with tissue-specific expression patterns using Akaike's information criterion procedure.

We applied a method based on Akaike's information criterion (AIC) to detect genes whose expression profile is considerably different in some tissue(s) than in others. Such observations are detected as outliers, and the method we used was originally developed to detect outliers. The main advantage of the method is that objective decisions are possible because the procedure is independent of a significance level. We applied the method to 48 expression ratios corresponding to various tissues in each of 14,610 clones obtained from the RIKEN Expression Array Database (READ; http://read.gsc.riken.go.jp). As a result, for several tissues (e.g., muscle, heart, and tongue tissues that contain similar cell types) we objectively obtained specific clones without any "thresholding." Our study demonstrates the feasibility of the method for detecting tissue-specific gene expression patterns.

Algorithms↗
PubMed2003

Discovery of imprinted transcripts in the mouse transcriptome using large-scale expression profiling.

Candidate imprinted transcriptional units in the mouse genome were identified systematically from 27,663 FANTOM2 full-length mouse cDNA clones by expression profiling. Large-scale cDNA microarrays were used to detect differential expression dependent upon chromosomal parent of origin by comparing the mRNA levels in the total tissue of 9.5 dpc parthenogenote and androgenote mouse embryos. Of the FANTOM2 transcripts, 2114 were identified as candidates on the basis of the array data. Of these, 39 mapped to known imprinted regions of the mouse genome, 56 were considered as nonprotein-coding RNAs, and 159 were natural antisense transcripts. The imprinted expression of two transcripts located in the mouse chromosomal region syntenic to the human Prader-Willi syndrome region was confirmed experimentally. We further mapped all candidate imprinted transcripts to the mouse and human genome and were shown in correlation with the imprinting disease loci. These data provide a major resource for understanding the role of imprinting in mammalian inherited traits.

Animals↗
PubMed2003

Continued discovery of transcriptional units expressed in cells of the mouse mononuclear phagocyte lineage.

The current RIKEN transcript set represents a significant proportion of the mouse transcriptome but transcripts expressed in the innate and acquired immune systems are poorly represented. In the present study we have assessed the complexity of the transcriptome expressed in mouse macrophages before and after treatment with lipopolysaccharide, a global regulator of macrophage gene expression, using existing RIKEN 19K arrays. By comparison to array profiles of other cells and tissues, we identify a large set of macrophage-enriched genes, many of which have obvious functions in endocytosis and phagocytosis. In addition, a significant number of LPS-inducible genes were identified. The data suggest that macrophages are a complex source of mRNA for transcriptome studies. To assess complexity and identify additional macrophage expressed genes, cDNA libraries were created from purified populations of macrophage and dendritic cells, a functionally related cell type. Sequence analysis revealed a high incidence of novel mRNAs within these cDNA libraries. These studies provide insights into the depths of transcriptional complexity still untapped amongst products of inducible genes, and identify macrophage and dendritic cell populations as a starting point for sampling the inducible mammalian transcriptome.

Animals↗
PubMed2003

Systematic expression profiling of the mouse transcriptome using RIKEN cDNA microarrays.

The number of known mRNA transcripts in the mouse has been greatly expanded by the RIKEN Mouse Gene Encyclopedia project. Validation of their reproducible expression in a tissue is an important contribution to the study of functional genomics. In this report, we determine the expression profile of 57,931 clones on 20 mouse tissues using cDNA microarrays. Of these 57,931 clones, 22,928 clones correspond to the FANTOM2 clone set. The set represents 20,234 transcriptional units (TUs) out of 33,409 TUs in the FANTOM2 set. We identified 7206 separate clones that satisfied stringent criteria for tissue-specific expression. Gene Ontology terms were assigned for these 7206 clones, and the proportion of 'molecular function' ontology for each tissue-specific clone was examined. These data will provide insights into the function of each tissue. Tissue-specific gene expression profiles obtained using our cDNA microarrays were also compared with the data extracted from the GNF Expression Atlas based on Affymetrix microarrays. One major outcome of the RIKEN transcriptome analysis is the identification of numerous nonprotein-coding mRNAs. The expression profile was also used to obtain evidence of expression for putative noncoding RNAs. In addition, 1926 clones (70%) of 2768 clones that were categorized as "unknown EST," and 1969 (58%) clones of 3388 clones that were categorized as "unclassifiable" were also shown to be reproducibly expressed.

Animals↗
PubMed2003

G protein-coupled receptor genes in the FANTOM2 database.

G protein-coupled receptors (GPCRs) comprise the largest family of receptor proteins in mammals and play important roles in many physiological and pathological processes. Gene expression of GPCRs is temporally and spatially regulated, and many splicing variants are also described. In many instances, different expression profiles of GPCR gene are accountable for the changes of its biological function. Therefore, it is intriguing to assess the complexity of the transcriptome of GPCRs in various mammalian organs. In this study, we took advantage of the FANTOM2 (Functional Annotation Meeting of Mouse cDNA 2) project, which aimed to collect full-length cDNAs inclusively from mouse tissues, and found 410 candidate GPCR cDNAs. Clustering of these clones into transcriptional units (TUs) reduced this number to 213. Out of these, 165 genes were represented within the known 308 GPCRs in the Mouse Genome Informatics (MGI) resource. The remaining 48 genes were new to mouse, and 14 of them had no clear mammalian ortholog. To dissect the detailed characteristics of each transcript, tissue distribution pattern and alternative splicing were also ascertained. We found many splicing variants of GPCRs that may have a relevance to disease occurrence. In addition, the difficulty in cloning tissue-specific and infrequently transcribed GPCRs is discussed further.

Alternative Splicing↗
PubMed2003

Targeting a complex transcriptome: the construction of the mouse full-length cDNA encyclopedia.

We report the construction of the mouse full-length cDNA encyclopedia,the most extensive view of a complex transcriptome,on the basis of preparing and sequencing 246 libraries. Before cloning,cDNAs were enriched in full-length by Cap-Trapper,and in most cases,aggressively subtracted/normalized. We have produced 1,442,236 successful 3'-end sequences clustered into 171,144 groups, from which 60,770 clones were fully sequenced cDNAs annotated in the FANTOM-2 annotation. We have also produced 547,149 5' end reads,which clustered into 124,258 groups. Altogether, these cDNAs were further grouped in 70,000 transcriptional units (TU),which represent the best coverage of a transcriptome so far. By monitoring the extent of normalization/subtraction, we define the tentative equivalent coverage (TEC),which was estimated to be equivalent to >12,000,000 ESTs derived from standard libraries. High coverage explains discrepancies between the very large numbers of clusters (and TUs) of this project,which also include non-protein-coding RNAs,and the lower gene number estimation of genome annotations. Altogether,5'-end clusters identify regions that are potential promoters for 8637 known genes and 5'-end clusters suggest the presence of almost 63,000 transcriptional starting points. An estimate of the frequency of polyadenylation signals suggests that at least half of the singletons in the EST set represent real mRNAs. Clones accounting for about half of the predicted TUs await further sequencing. The continued high-discovery rate suggests that the task of transcriptome discovery is not yet complete.

Animals↗
PubMed2003

Analysis of the mouse transcriptome for genes involved in the function of the nervous system.

We analyzed the mouse Representative Transcript and Protein Set for molecules involved in brain function. We found full-length cDNAs of many known brain genes and discovered new members of known brain gene families, including Family 3 G-protein coupled receptors, voltage-gated channels, and connexins. We also identified previously unknown candidates for secreted neuroactive molecules. The existence of a large number of unique brain ESTs suggests an additional molecular complexity that remains to be explored.A list of genes containing CAG stretches in the coding region represents a first step in the potential identification of candidates for hereditary neurological disorders.

Adenine↗
PubMed2003

Comprehensive analysis of the mouse metabolome based on the transcriptome.

The complete set of cDNAs encoding the enzymes of known metabolic pathways has not previously been available for any mammal. Here, transcripts encoding the metabolic pathways of the mouse (mouse metabolome) were reconstructed by making use of the KEGG metabolic pathway database and gene ontology (GO) assignment to the mouse representative transcript and protein set (RTPS), which contains all available mouse transcript sequences including the FANTOM set of RIKEN mouse cDNA clones. By assigning EC numbers extracted from the molecular function ontology in GO, the known mouse transcriptome was predicted to encode enzymes with 726 unique EC numbers. Of these, 648 EC numbers were newly assigned based on the FANTOM set. The mouse metabolome confirmed by cDNA analysis includes almost all of the enzymes of well known pathways such as the tricarboxylic acid cycle and urea cycle. On the other hand, analysis of enzymes required for the tryptophan metabolism pathway revealed a lack of connectivity, indicating that cDNAs/genes encoding several key enzymes remain to be identified. The information derived from coexpression from the cDNA microarray analysis of enzymes of known function may lead to identification of the missing components of the metabolome, and will add new insights into the connectivity of the mammalian metabolic pathways.

Amino Acids↗
PubMed2003

Human disease genes and their cloned mouse orthologs: exploration of the FANTOM2 cDNA sequence data set.

The FANTOM2 cDNA sequence data set is an excellent model to demonstrate the power of large-scale cDNA sequencing, with the goal of providing a full-length transcript sequence for each mouse gene. This data set enhances the use of the mouse as a model for human disease. Here we identify mouse cDNA sequences in the FANTOM2 data set for a set of 67 human disease genes that as of May 2002 had no corresponding mouse cDNA annotated in the Mouse Genome Informatics (MGI) database. These 67 human disease genes include genes related to neurological and eye disorders and cancer. We also present a list of the human disease genes and their cloned mouse orthologs found in two public databases, LocusLink and MGI. Allelic variant and gene functional information available in MGI provides additional information relative to these mouse models, whereas computed sequence-based connections at NCBI support facile navigation through multiple genomes.

Alleles↗