Database Of Transcriptional Start Sites Research Articles

Immune Factors Drive Expression of SARS-CoV-2 Receptor Genes Amid Sexual Disparity.

The emergence of COVID-19 has led to significant morbidity and mortality, with around seven million deaths worldwide as of February 2023. There are several risk factors such as age and sex that are associated with the development of severe symptoms due to COVID-19. There have been limited studies that have explored the role of sex differences in SARS-CoV-2 infection. As a result, there is an urgent need to identify molecular features associated with sex and COVID-19 pathogenesis to develop more effective interventions to combat the ongoing pandemic. To address this gap, we explored sex-specific molecular factors in both mouse and human datasets. The host immune targets such as TLR7, IRF7, IRF5, and IL6, which are involved in the immune response against viral infections, and the sex-specific targets such as AR and ESSR were taken to investigate any possible link with the SARS-CoV-2 host receptors ACE2 and TMPRSS2. For the mouse analysis, a single-cell RNA sequencing dataset was used, while bulk RNA-Seq datasets were used to analyze the human clinical data. Additional databases such as the Database of Transcription Start Sites (DBTS), STRING-DB, and the Swiss Regulon Portal were used for further analysis. We identified a 6-gene signature that showed differential expression in males and females. Additionally, this gene signature showed potential prognostic utility by differentiating ICU patients from non-ICU patients due to COVID-19. Our study highlights the importance of assessing sex differences in SARS-CoV-2 infection, which can assist in the optimal treatment and better vaccination strategies.

Classification and characterization of alternative promoters in 26 lung adenocarcinoma cell lines.

Genome-wide landscape of alternative promoter use remains unknown. We determined expression profiles of promoters in 26 lung adenocarcinoma cell lines using the transcriptional start site-sequencing data and proposed an index 'canonical promoter usage' to quantify the diversity of alternative promoter usage. Transcriptional start site-sequencing and other datasets were obtained from the DataBase of Transcriptional Start Sites. Transcriptional start site-sequencing read clusters were mapped onto RefGene to determine the promoters. Commonly used promoters were designated as canonical promoters. The sequence logos, CpG islands, DNA methylation and histone modifications of canonical and non-canonical promoters were examined. Canonical promoter usage was calculated by dividing 'read counts of a canonical promoter' by 'read counts of all the units of promoters' on each gene. The expressed genes were subjected to hierarchical clustering according to their canonical promoter usage. Among 104 455 promoters for 14 297 genes, 8659 canonical and 68 197 non-canonical promoters were identified. Corresponding to higher expression, canonical promoters showed core promoter sequences, higher CpG island positivity, less DNA methylation and higher transcription-promoting histone modifications. Gene ontology enrichment analysis revealed that the clusters with lower canonical promoter usage were related to signalling pathways, whereas clusters of tightly regulated genes with higher canonical promoter usage were related to housekeeping genes. Canonical promoters were regulated by conventional transcriptional machinery, while non-canonical promoters would be targets of 'leaky' expression. Further investigation is warranted to analyse the correlation between alternative promoter usage and biological characteristics contributing to carcinogenesis.

Implications of differential transcription start site selection on chronic myeloid leukemia and prostate cancer cell protein expression.

The relevance of minor transcription start sites in broad promoters is not well understood. We have studied AGAP2 expression in prostate cancer and chronic myeloid leukemia (CML), showing transcription is initiated from alternative transcription start sites (TSSs) within a single TSS cluster, producing cancer-type-specific AGAP2 mRNAs with small differences in their 5' UTR length. Interestingly, in the CML cell lines where the 5' UTR is longer, AGAP2 protein levels are lower. We demonstrate that the selection of an upstream TSS involved the formation of a G quadruplex in the 5' UTR, decreasing polysome formation. After developing a bioinformatics pipeline to query data from the FANTOM project and the NCl-60 human tumor cell lines screen, we found HK1 expression can also be regulated by the same mechanism. Overall, we present compelling data supporting TSS selection within a TSS cluster play a role in protein expression and should not be ignored.

Translation of Tudor-SN, a novel terminal oligo-pyrimidine (TOP) mRNA, is regulated by the mTORC1 pathway in cardiomyocytes

ABSTRACT The mechanisms that regulate cell-cycle arrest of cardiomyocytes during heart development are largely unknown. We have previously identified Tudor staphylococcal nuclease (Tudor-SN) as a cell-cycle regulator and have shown that its expression level was closely related to cell-proliferation capacity. Herein, we found that Tudor-SN was highly expressed in neonatal mouse myocardia, but it was lowly expressed in that of adults. Using Data Base of Transcription Start Sites (DBTSS), we revealed that Tudor-SN was a terminal oligo-pyrimidine (TOP) mRNA. We further confirmed that the translational efficiency of Tudor-SN mRNA was controlled by the mammalian target of rapamycin complex 1 (mTORC1) pathway, as revealed via inhibition of activated mTORC1 in primary neonatal mouse cardiomyocytes and activation of silenced mTORC1 in adult mouse myocardia; additionally, this result was recapitulated in H9c2 cells. We also demonstrated that the downregulation of Tudor-SN in adult myocardia was due to inactivation of the mTORC1 pathway to ensure that heart growth was in proportion to that of the rest of the body. Moreover, we revealed that Tudor-SN participated in the mTORC1-mediated regulation of cardiomyocytic proliferation, which further elucidated the correlation between Tudor-SN and the mTORC1 pathway. Taken together, our findings suggest that the translational efficiency of Tudor-SN is regulated by the mTORC1 pathway in myocardia and that Tudor-SN is involved in mTORC1-mediated regulation of cardiomyocytic proliferation and cardiac development.

DBTSS/DBKERO for integrated analysis of transcriptional regulation.

DBTSS (Database of Transcriptional Start Sites)/DBKERO (Database of Kashiwa Encyclopedia for human genome mutations in Regulatory regions and their Omics contexts) is the database originally initiated with the information of transcriptional start sites and their upstream transcriptional regulatory regions. In recent years, we updated the database to assist users to elucidate biological relevance of the human genome variations or somatic mutations in cancers which may affect the transcriptional regulation. In this update, we facilitate interpretations of disease associated genomic variation, using the Japanese population as a model case. We enriched the genomic variation dataset consisting of the 13,368 individuals collected for various genome-wide association studies and the reference epigenome information in the surrounding regions using a total of 455 epigenome datasets (four tissue types from 67 healthy individuals) collected for the International Human Epigenome Consortium (IHEC). The data directly obtained from the clinical samples was associated with that obtained from various model systems, such as the drug perturbation datasets using cultured cancer cells. Furthermore, we incorporated the results obtained using the newly developed analytical methods, Nanopore/10x Genomics long-read sequencing of the human genome and single cell analyses. The database is made publicly accessible at the URL (http://dbtss.hgc.jp/).

Small RNA-Mediated Epigenetic Myostatin Silencing

Myostatin (Mstn) is a secreted growth factor that negatively regulates muscle mass and is therefore a potential pharmacological target for the treatment of muscle wasting disorders such as Duchenne muscular dystrophy. Here we describe a novel Mstn blockade approach in which small interfering RNAs (siRNAs) complementary to a promoter-associated transcript induce transcriptional gene silencing (TGS) in two differentiated mouse muscle cell lines. Silencing is sensitive to treatment with the histone deacetylase inhibitor trichostatin A, and the silent state chromatin mark H3K9me2 is enriched at the Mstn promoter following siRNA transfection, suggesting epigenetic remodeling underlies the silencing effect. These observations suggest that long-term epigenetic silencing may be feasible for Mstn and that TGS is a promising novel therapeutic strategy for the treatment of muscle wasting disorders.

DBTSS: DataBase of Transcriptional Start Sites progress report in 2012

To support transcriptional regulation studies, we have constructed DBTSS (DataBase of Transcriptional Start Sites), which contains exact positions of transcriptional start sites (TSSs), determined with our own technique named TSS-seq, in the genomes of various species. In its latest version, DBTSS covers the data of the majority of human adult and embryonic tissues: it now contains 418 million TSS tag sequences from 28 tissues/cell cultures. Moreover, we integrated a series of our own transcriptomic data, such as the RNA-seq data of subcellular-fractionated RNAs as well as the ChIP-seq data of histone modifications and the binding of RNA polymerase II/several transcription factors in cultured cell lines into our original TSS information. We also included several external epigenomic data, such as the chromatin map of the ENCODE project. We further associated our TSS information with public or original single-nucleotide variation (SNV) data, in order to identify SNVs in the regulatory regions. These data can be browsed in our new viewer, which supports versatile search conditions of users. We believe that our new DBTSS will be an invaluable resource for interpreting the differential uses of TSSs and for identifying human genetic variations that are associated with disordered transcriptional regulation. DBTSS can be accessed at http://dbtss.hgc.jp.

Gene Expression and Transcription Factor Profiling Reveal Inhibition of Transcription Factor cAMP-response Element-binding Protein by γ-Herpesvirus Replication and Transcription Activator

Herpesvirus replication involves the expression of over 80 viral genes in a well ordered sequence, leading to the production of new virions. Viral genes expressed during the earliest phases of replication often regulate both viral and cellular genes. Therefore, they have the potential to bring about dramatic functional changes within the cell. Replication and transcription activator (RTA) is a potent immediate early transcription activator of the gamma-herpesvirus family. This family includes Epstein-Barr virus and Kaposi sarcoma-associated herpesvirus, human pathogens associated with malignancy. Here we combine gene array technology with transcription factor profiling to identify the earliest DNA promoter and cellular transcription factor targets of RTA in the cellular genome. We find that expression of RTA leads to both activation and inhibition of distinct groups of cellular genes. The identity of the target genes suggests that RTA rapidly changes the cellular environment to counteract cell death pathways, support growth factor signaling, and also promote immune evasion of the infected cell. Transcription factor profiling of the target gene promoters highlighted distinct pathways involved in gene activation at specific time points. Most notable throughout was the high level of cAMP-response element-binding protein (CREB)-response elements in RTA target genes. We find that RTA can function as either an activator or an inhibitor of CREB-response genes, depending on the promoter context. The association with CREB also highlights a novel connection and coordination between viral and cellular "immediate early" responses.

DBTSS provides a tissue specific dynamic view of Transcription Start Sites

DataBase of Transcription Start Sites (DBTSS) is a database which contains precise positional information for transcription start sites (TSSs) of eukaryotic mRNAs. In this update, we included 330 million new tags generated by massively sequencing the 5′-end of oligo-cap selected cDNAs in humans and mice. The tags were collected from normal fetal or adult human tissues, including brain, thymus, liver, kidney and heart, from 6 human cell lines in 21 diverse growth conditions as well as from mouse NIH3T3 cell line: altogether 31 different cell types or culture conditions are represented. This unprecedented increase in depth of data now allows DBTSS to faithfully represent the dynamically changing landscape of TSSs in different cell types and conditions, during development and in the course of evolution. Differential usage of alternative 5′-ends across cell types and conditions can be viewed in a series of new interfaces. Promoter sequence information is now displayed in a comparative genomics viewer where evolutionary turnover of the TSSs can be evaluated. DBTSS can be accessed at http://dbtss.hgc.jp/.

DBTSS: database of transcription start sites, progress report 2008

DBTSS is a database of transcriptional start sites, based on our unique collection of precise, experimentally determined 5′-end sequences of full-length cDNAs. Since its first release in 2002, several major updates have been made. In this update, we expanded the human transcriptional start site dataset by 19 million uniquely mapped, and RefSeq-associated, 5′-end sequences, which were generated by a newly introduced Solexa sequencer. Moreover, in order to provide means for interpreting those massive TSS data, we implemented two new analytical tools: one for connecting expression information with predicted transcription factor binding sites; the other for examining evolutionary conservation or species-specificity of promoters and transcripts, which can be browsed by our own comparative genome viewer. With the expanded dataset and the enhanced functionalities, DBTSS provides a unique platform that enables in-depth transcriptome analyses. DBTSS is accessible at http://dbtss.hgc.jp/.

Diversity of Translation Start Sites May Define Increased Complexity of the Human Short ORFeome

Our previous proteomics analysis of small proteins expressed in human K562 cells provided the first direct evidence of translation of upstream ORFs in human full-length cDNAs (Oyama, M., Itagaki, C., Hata, H., Suzuki, Y., Izumi, T., Natsume, T., Isobe, T., and Sugano, S. (2004) Analysis of small human proteins reveals the translation of upstream open reading frames of mRNAs. Genome Res. 14, 2048-2052). In the present study, we performed an in-depth proteomics analysis of human K562 and HEK293 cells using a two-dimensional nano-liquid chromatography-tandem mass spectrometry system. The results led to the identification of eight protein-coding regions besides 197 small proteins with a theoretical mass less than 20 kDa that were already annotated coding sequences in the curated mRNA database. In addition to the upstream ORFs in the presumed 5'-untranslated regions of mRNAs, bioinformatics analysis based on accumulated 5'-end cDNA sequence data provided evidence of novel short coding regions that were likely to be translated from the upstream non-AUG start site or from the new short transcript variants generated by utilization of downstream alternative promoters. Protein expression analysis of the GRINL1A gene revealed that translation from the most upstream start site occurred on the minor alternative splicing transcript, whereas this initiation site was not utilized on the major mRNA, resulting in translation of the downstream ORF from the second initiation codon. These findings reveal a novel post-transcriptional system that can augment the human proteome via the alternative use of diverse translation start sites coupled with transcriptional regulation through alternative promoters or splicing, leading to increased complexity of short protein-coding regions defined by the human transcriptome.

Genome Wide Analysis Reveals Strong Correlation between CpG Islands and Tissue-Specificity

Vertebrate genomes contain GC-rich or poor compartments, called isochores, It has been reported that heavy isochores (GC-rich) contain housekeeping genes while light ischores (GC-rich) have tissuespecific genes [1]. On the other hand, it was mentioned oppositely that there was no correlation between GC contents and tissue specificity [4, 5]. One of the major reasons for this conflicting idea is probably caused by the inaccurate information of transcription start site (TSS) in each gene. Recently, we constructed DBTSS: DataBase of Transcription Start Sites [6]. In this database, the clones which were constructed by the oligo-capping method show TSSs of a gene with high accuracy. Here we used data in DBTSS to determine precise TSSs and studied correlation between CpG islands and tissue-specificity using them.

Oligo-capped cDNAs for promoter identification and annotation

In order to obtain precise information of 5′ end of mRNAs, we have developed the oligo-capping method that replaces the cap of mRNA with synthetic oligonucleotides. Using the data from oligo-capped cDNAs, we constructed database of transcriptional start sites (DBTSS; http://elmo.ims.u-tokyo.ac.jp/dbtss/). This database shows the information on distribution of transcriptional start sites and can be used to identify the core promoter region. Here we show the summery and the update of DBTSS and its future use on identification of regulatory motifs within the promoter.

A database of transcriptional start sites

Knowledge of the exact transcriptional start site of a gene is crucial for the assignment and study of its promoter region and, sometimes, to obtain the entire protein coding region. Correct assignment of the transcriptional start site is not an easy task. Most cDNAs currently deposited in databases do not contain the sequences from the 5′ ends of genes largely because of the difficulty in obtaining full-length clones. Even though sequencing of the human genome has been completed, the number of entries in the eukaryotic promoter database is only in the hundreds.In a recent report, Suzuki et al. [1xDBTSS: database of human transcriptional start sites and full-length cDNAs. Suzuki, Y et al. Nucleic Acids Res. 2002; 30: 328–331Crossref | PubMedSee all References][1] describe a database containing the transcriptional start sites of thousands of genes along with their location on the human draft genome sequence. They created this database by generating and sequencing cDNA libraries that are specifically derived from mRNA species containing a 5′ cap structure (oligo-capping method). This procedure enriches for full-length clones. Over 111 000 clones derived from 132 libraries were used to extend the 5′ ends of these genes by an average of 87 base pairs. They obtained clones corresponding to 7889 human genes in the reference sequence database (RefSeq) project initiated by the National Center for Biotechnology Information (NCBI) and were able to further extend the 5′ ends of 59% of these. Strikingly, the authors found that the transcriptional start sites for >1000 of these genes were located >10 kilobases upstream of the currently assigned sites owing to the presence of large introns.This database (http://elmo.ims.u-tokyo.ac.jp/dbtss) can be searched using a gene symbol, gene definition, RefSeq ID, Locus link ID or UniGene ID. Alternatively, one can perform a BLAST search against the database to see whether a longer version of a cDNA exists. The search results are presented in an organized format: the top part of the output shows the genomic context of the gene (exon–intron structure) with the transcriptional start site(s) clearly marked, whereas the bottom part depicts the original RefSeq sequence along with any additional 5′ sequence. This database, which will be updated periodically, will be useful for anyone who wishes to characterize and study human genes in detail. One would hope that the additional sequence data generated by Suzuki et al. would ultimately be incorporated into RefSeq and other databases for wider dissemination of the information.

DBTSS: DataBase of human Transcriptional Start Sites and full-length cDNAs.

Although the information of cDNAs is indispensable for analyzing gene function, most of the cDNA sequences stored in current databases are imperfect in the sense that they lack the precise information of 5' end termini. To overcome this difficulty, we have developed the oligo-capping method to obtain full-length cDNAs, the information of which has been partly deposited in public databases. In this study, we further constructed human cDNA libraries enriched in clones containing the cap structure to systematically explore the 5' end structure of expressed genes. Of approximately 217 402 5' end sequences obtained, 111 382 have been matched to cDNA sequences of known genes (7889 genes) and are presented in our new database, DataBase of Transcriptional Start Sites (DBTSS; http://elmo.ims.u-tokyo.ac.jp/dbtss/). Sequence comparison between our entries and those of a reference sequence database, RefSeq, revealed that 4683 (34%) of RefSeq sequences should be extended towards the 5' ends. We also mapped each sequence on the human draft genome sequence to identify its transcriptional start site, which provides us with more detailed information on distribution patterns of transcriptional start sites and adjacent regulatory regions.