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author:("tateo, Yoshio")
1.  Divergence of East Asians and Europeans Estimated Using Male- and Female-Specific Genetic Markers 
Genome Biology and Evolution  2014;6(3):466-473.
To study the male and female lineages of East Asian and European humans, we have sequenced 25 short tandem repeat markers on 453 Y-chromosomes and collected sequences of 72 complete mitochondrial genomes to construct independent phylogenetic trees for male and female lineages. The results indicate that East Asian individuals fall into two clades, one that includes East Asian individuals only and a second that contains East Asian and European individuals. Surprisingly, the European individuals did not form an independent clade, but branched within in the East Asians. We then estimated the divergence time of the root of the European clade as ∼41,000 years ago. These data indicate that, contrary to traditional views, Europeans diverged from East Asians around that time. We also address the origin of the Ainu lineage in northern Japan.
PMCID: PMC3971580  PMID: 24589501
human evolution; individual lineages; mitochondrial DNA; Y-STR; East Asians; Europeans
2.  Evolutionary conserved microRNAs are ubiquitously expressed compared to tick-specific miRNAs in the cattle tick Rhipicephalus (Boophilus) microplus 
BMC Genomics  2011;12:328.
MicroRNAs (miRNAs) are small non-coding RNAs that act as regulators of gene expression in eukaryotes modulating a large diversity of biological processes. The discovery of miRNAs has provided new opportunities to understand the biology of a number of species. The cattle tick, Rhipicephalus (Boophilus) microplus, causes significant economic losses in cattle production worldwide and this drives us to further understand their biology so that effective control measures can be developed. To be able to provide new insights into the biology of cattle ticks and to expand the repertoire of tick miRNAs we utilized Illumina technology to sequence the small RNA transcriptomes derived from various life stages and selected organs of R. microplus.
To discover and profile cattle tick miRNAs we employed two complementary approaches, one aiming to find evolutionary conserved miRNAs and another focused on the discovery of novel cattle-tick specific miRNAs. We found 51 evolutionary conserved R. microplus miRNA loci, with 36 of these previously found in the tick Ixodes scapularis. The majority of the R. microplus miRNAs are perfectly conserved throughout evolution with 11, 5 and 15 of these conserved since the Nephrozoan (640 MYA), Protostomian (620MYA) and Arthropoda (540 MYA) ancestor, respectively. We then employed a de novo computational screening for novel tick miRNAs using the draft genome of I. scapularis and genomic contigs of R. microplus as templates. This identified 36 novel R. microplus miRNA loci of which 12 were conserved in I. scapularis. Overall we found 87 R. microplus miRNA loci, of these 15 showed the expression of both miRNA and miRNA* sequences. R. microplus miRNAs showed a variety of expression profiles, with the evolutionary-conserved miRNAs mainly expressed in all life stages at various levels, while the expression of novel tick-specific miRNAs was mostly limited to particular life stages and/or tick organs.
Anciently acquired miRNAs in the R. microplus lineage not only tend to accumulate the least amount of nucleotide substitutions as compared to those recently acquired miRNAs, but also show ubiquitous expression profiles through out tick life stages and organs contrasting with the restricted expression profiles of novel tick-specific miRNAs.
PMCID: PMC3141673  PMID: 21699734
3.  HGT-Gen: a tool for generating a phylogenetic tree with horizontal gene transfer 
Bioinformation  2011;7(5):211-213.
Horizontal gene transfer (HGT) is a common event in prokaryotic evolution. Therefore, it is very important to consider HGT in the study of molecular evolution of prokaryotes. This is true also for conducting computer simulations of their molecular phylogeny because HGT is known to be a serious disturbing factor for estimating their correct phylogeny. To the best of our knowledge, no existing computer program has generated a phylogenetic tree with HGT from an original phylogenetic tree. We developed a program called HGT-Gen that generates a phylogenetic tree with HGT on the basis of an original phylogenetic tree of a protein or gene. HGT-Gen converts an operational taxonomic unit or a clade from one place to another in a given phylogenetic tree. We have also devised an algorithm to compute the average length between any pair of branches in the tree. It defines and computes the relative evolutionary time to normalize evolutionary time for each lineage. The algorithm can generate an HGT between a pair of donor and acceptor lineages at the same evolutionary time. HGT-Gen is used with a sequence-generating program to evaluate the influence of HGT on the molecular phylogeny of prokaryotes in a computer simulation study.
The database is available for free at˜thoriike/HGT-Gen.html
PMCID: PMC3218414  PMID: 22125388
4.  Phylogenetic construction of 17 bacterial phyla by new method and carefully selected orthologs 
Gene  2008;429(1-2):59-64.
Here, we constructed a phylogenetic tree of 17 bacterial phyla covering eubacteria and archaea by using a new method and 102 carefully selected orthologs from their genomes. One of the serious disturbing factors in phylogeny construction is the existence of out-paralogs that cannot easily be found out and discarded. In our method, out-paralogs are detected and removed by constructing a phylogenetic tree of the genes in question and examining the clustered genes in the tree. We also developed a method for comparing two tree topologies or shapes, ComTree. Applying ComTree to the constructed tree we computed the relative number of orthologs that support a node of the tree. This number is called the Positive Ortholog Ratio (POR), which is conceptually and methodologically different from the frequently used bootstrap value. Our study concretely shows drawbacks of the bootstrap test. Our result of bacterial phylogeny analysis is consistent with previous ones showing that hyperthermophilic bacteria such as Thermotogae and Aquificae diverged earlier than the others in the eubacterial phylogeny studied. It is noted that our results are consistent whether thermophilic archaea or mesophilic archaea is employed for determining the root of the tree. The earliest divergence of hyperthermophilic eubacteria is supported by genes involved in fundamental metabolic processes such as glycolysis, nucleotide and amino acid syntheses.
PMCID: PMC2648810  PMID: 19000750
Bacterial phylogeny; Concatenated tree; Out-paralog; Ortholog database; Thermophilic eubacteria; Tree evaluation
5.  The GTOP database in 2009: updated content and novel features to expand and deepen insights into protein structures and functions 
Nucleic Acids Research  2008;37(Database issue):D333-D337.
The Genomes TO Protein Structures and Functions (GTOP) database ( freely provides an extensive collection of information on protein structures and functions obtained by application of various computational tools to the amino acid sequences of entirely sequenced genomes. GTOP contains annotations of 3D structures, protein families, functions, and other useful data of a protein of interest in user-friendly ways to give a deep insight into the protein structure. From the initial 1999 version, GTOP has been continually updated to reap the fruits of genome projects and augmented to supply novel information, in particular intrinsically disordered regions. As intrinsically disordered regions constitute a considerable fraction of proteins and often play crucial roles especially in eukaryotes, their assignments give important additional clues to the functionality of proteins. Additionally, we have incorporated the following features into GTOP: a platform independent structural viewer, results of HMM searches against SCOP and Pfam, secondary structure predictions, color display of exon boundaries in eukaryotic proteins, assignments of gene ontology terms, search tools, and master files.
PMCID: PMC2686575  PMID: 18987007
6.  DDBJ dealing with mass data produced by the second generation sequencer 
Nucleic Acids Research  2008;37(Database issue):D16-D18.
DNA Data Bank of Japan (DDBJ) ( collected and released 2 368 110 entries or 1 415 106 598 bases in the period from July 2007 to June 2008. The releases in this period include genome scale data of Bombyx mori, Oryzas latipes, Drosophila and Lotus japonicus. In addition, from this year we collected and released trace archive data in collaboration with National Center for Biotechnology Information (NCBI). The first release contains those of O. latipes and bacterial meta genomes in human gut. To cope with the current progress of sequencing technology, we also accepted and released more than 100 million of short reads of parasitic protozoa and their hosts that were produced by using a Solexa sequencer.
PMCID: PMC2686496  PMID: 18927114
7.  BioCaster: detecting public health rumors with a Web-based text mining system 
Bioinformatics  2008;24(24):2940-2941.
Summary: BioCaster is an ontology-based text mining system for detecting and tracking the distribution of infectious disease outbreaks from linguistic signals on the Web. The system continuously analyzes documents reported from over 1700 RSS feeds, classifies them for topical relevance and plots them onto a Google map using geocoded information. The background knowledge for bridging the gap between Layman's terms and formal-coding systems is contained in the freely available BioCaster ontology which includes information in eight languages focused on the epidemiological role of pathogens as well as geographical locations with their latitudes/longitudes. The system consists of four main stages: topic classification, named entity recognition (NER), disease/location detection and event recognition. Higher order event analysis is used to detect more precisely specified warning signals that can then be notified to registered users via email alerts. Evaluation of the system for topic recognition and entity identification is conducted on a gold standard corpus of annotated news articles.
Availability: The BioCaster map and ontology are freely available via a web portal at
PMCID: PMC2639299  PMID: 18922806
8.  eGenomics: Cataloguing Our Complete Genome Collection III 
This meeting report summarizes the proceedings of the “eGenomics: Cataloguing our Complete Genome Collection III” workshop held September 11–13, 2006, at the National Institute for Environmental eScience (NIEeS), Cambridge, United Kingdom. This 3rd workshop of the Genomic Standards Consortium was divided into two parts. The first half of the three-day workshop was dedicated to reviewing the genomic diversity of our current and future genome and metagenome collection, and exploring linkages to a series of existing projects through formal presentations. The second half was dedicated to strategic discussions. Outcomes of the workshop include a revised “Minimum Information about a Genome Sequence” (MIGS) specification (v1.1), consensus on a variety of features to be added to the Genome Catalogue (GCat), agreement by several researchers to adopt MIGS for imminent genome publications, and an agreement by the EBI and NCBI to input their genome collections into GCat for the purpose of quantifying the amount of optional data already available (e.g., for geographic location coordinates) and working towards a single, global list of all public genomes and metagenomes.
PMCID: PMC1872051
9.  DDBJ working on evaluation and classification of bacterial genes in INSDC 
Nucleic Acids Research  2006;35(Database issue):D13-D15.
DNA Data Bank of Japan (DDBJ) () newly collected and released 12 927 184 entries or 13 787 688 598 bases in the period from July 2005 to June 2006. The released data contain honeybee expressed sequence tags (ESTs), re-examined and re-annotated complete genome data of Escherichia coli K-12 W3110, medaka WGS and human MGA. We also systematically evaluated and classified the genes in the complete bacterial genomes submitted to the International Nucleotide Sequence Database Collaboration (INSDC, ) that is composed of DDBJ, EMBL Bank and GenBank. The examination and classification selected 557 000 genes as reliable ones among all the bacterial genes predicted by us.
PMCID: PMC1669713  PMID: 17108353
10.  DDBJ in preparation for overview of research activities behind data submissions 
Nucleic Acids Research  2005;34(Database issue):D6-D9.
In the past year, DDBJ () collected and released 1 956 826 entries or 1 741 313 111 bases. The released data include ∼90 000 ESTs and cDNAs of Macaca fascicularis, and 280 million bases of mouse GSS. In addition to the data collection, we have indexed the submitted data to the International Nucleotide Sequence Database Collaboration (INSDC, ) to classify the entries into research projects behind data submissions. They are expected to be useful to the data submitters and users for enhancing the data submission, retrieval and systematic data analyses at INSDC. The results of indexing also allow one to grasp research projects in life sciences that promoted and produced the DNA sequences submitted to INSDC.
PMCID: PMC1347473  PMID: 16381940
12.  Structural and Functional Differences in Two Cyclic Bacteriocins with the Same Sequences Produced by Lactobacilli 
Lactobacillus gasseri LA39 and L. reuteri LA6 isolated from feces of the same human infant were found to produce similar cyclic bacteriocins (named gassericin A and reutericin 6, respectively) that cannot be distinguished by molecular weights or primary amino acid sequences. However, reutericin 6 has a narrower spectrum than gassericin A. In this study, gassericin A inhibited the growth of L. reuteri LA6, but reutericin 6 did not inhibit the growth of L. gasseri LA39. Both bacteriocins caused potassium ion efflux from indicator cells and liposomes, but the amounts of efflux and patterns of action were different. Although circular dichroism spectra of purified bacteriocins revealed that both antibacterial peptides are composed mainly of α-helices, the spectra of the bacteriocins did not coincide. The results of d- and l-amino acid composition analysis showed that two residues and one residue of d-Ala were detected among 18 Ala residues of gassericin A and reutericin 6, respectively. These findings suggest that the different d-alanine contents of the bacteriocins may cause the differences in modes of action, amounts of potassium ion efflux, and secondary structures. This is the first report that characteristics of native bacteriocins produced by wild lactobacillus strains having the same structural genes are influenced by a difference in d-amino acid contents in the molecules.
PMCID: PMC404377  PMID: 15128550
13.  DNA Data Bank of Japan (DDBJ) in collaboration with mass sequencing teams 
Nucleic Acids Research  2000;28(1):24-26.
We at DDBJ ( ) process and publicise the massive amounts of data submitted mainly by Japanese genome projects and sequencing teams. It is emphasised that the collaboration between data producing teams and the data bank is crucial in carrying out these processes smoothly. The amount of data submitted in 1999 is so large that it alone exceeds the total amount submitted in the preceding 10 years. To cope with this situation, we have developed tools not only for processing such massive amounts of data but also for efficiently retrieving data on demand.
PMCID: PMC102400  PMID: 10592172
14.  Submission of Microarray Data to Public Repositories 
PLoS Biology  2004;2(9):e317.
The Microarray Gene Expression Data Society believe that the time is right for journals to require that microarray data be deposited in public repositories, as a condition for publication
PMCID: PMC514887  PMID: 15340489

Results 1-14 (14)