Kaname Kojima, R. Yamaguchi, S. Imoto, Mai Yamauchi, Masao Nagasaki, Ryo Yoshida, Teppei Shimamura, Kazuko Ueno, T. Higuchi, N. Gotoh, S. Miyano
{"title":"A state space representation of VAR models with sparse learning for dynamic gene networks.","authors":"Kaname Kojima, R. Yamaguchi, S. Imoto, Mai Yamauchi, Masao Nagasaki, Ryo Yoshida, Teppei Shimamura, Kazuko Ueno, T. Higuchi, N. Gotoh, S. Miyano","doi":"10.1142/9781848165786_0006","DOIUrl":"https://doi.org/10.1142/9781848165786_0006","url":null,"abstract":"We propose a state space representation of vector autoregressive model and its sparse learning based on L1 regularization to achieve efficient estimation of dynamic gene networks based on time course microarray data. The proposed method can overcome drawbacks of the vector autoregressive model and state space model; the assumption of equal time interval and lack of separation ability of observation and systems noises in the former method and the assumption of modularity of network structure in the latter method. However, in a simple implementation the proposed model requires the calculation of large inverse matrices in a large number of times during parameter estimation process based on EM algorithm. This limits the applicability of the proposed method to a relatively small gene set. We thus introduce a new calculation technique for EM algorithm that does not require the calculation of inverse matrices. The proposed method is applied to time course microarray data of lung cells treated by stimulating EGF receptors and dosing an anticancer drug, Gefitinib. By comparing the estimated network with the control network estimated using non-treated lung cells, perturbed genes by the anticancer drug could be found, whose up- and down-stream genes in the estimated networks may be related to side effects of the anticancer drug.","PeriodicalId":73143,"journal":{"name":"Genome informatics. International Conference on Genome Informatics","volume":"17 1","pages":"56-68"},"PeriodicalIF":0.0,"publicationDate":"2010-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89889175","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Masataka Takarabe, D. Shigemizu, Masaaki Kotera, S. Goto, M. Kanehisa
{"title":"Characterization and classification of adverse drug interactions.","authors":"Masataka Takarabe, D. Shigemizu, Masaaki Kotera, S. Goto, M. Kanehisa","doi":"10.1142/9781848165786_0014","DOIUrl":"https://doi.org/10.1142/9781848165786_0014","url":null,"abstract":"Drug interactions which may cause harmful events are important for our health and new drag development. In the previous work, we extracted the drug interaction data from Japanese drug package inserts and generated the drug interaction network. The network contains a large number of drugs densely connected to each other, where drug targets and drug-metabolizing enzymes were shared in the drug interactions. In this study, we further analyzed the obtained drug interaction network by merging drugs into drug categories based on the Anatomical Therapeutic Chemical (ATC) classification. The merged data of drug interactions indicated drug properties that are related to drug interaction mechanisms or symptoms. We investigated the relationships between the drug groups and drug interaction mechanisms or symptoms.","PeriodicalId":73143,"journal":{"name":"Genome informatics. International Conference on Genome Informatics","volume":"18 1","pages":"167-75"},"PeriodicalIF":0.0,"publicationDate":"2010-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82457059","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yang Zhao, Takeyuki Tamura, M. Hayashida, T. Akutsu
{"title":"A dynamic programming algorithm to predict synthesis processes of tree-structured compounds with graph grammar.","authors":"Yang Zhao, Takeyuki Tamura, M. Hayashida, T. Akutsu","doi":"10.1142/9781848166585_0018","DOIUrl":"https://doi.org/10.1142/9781848166585_0018","url":null,"abstract":"For several decades, many methods have been developed for predicting organic synthesis paths. However these methods have non-polynomial computational time. In this paper, we propose a bottom-up dynamic programming algorithm to predict synthesis paths of target tree-structured compounds. In this approach, we transform the synthesis problem of tree-structured compounds to the generation problem of unordered trees by regarding tree-structured compounds and chemical reactions as unordered trees and rules, respectively. In order to represent rules corresponding to chemical reactions, we employ a subclass of NLC (Node Label Controlled) grammars. We also give some computational results on this algorithm.","PeriodicalId":73143,"journal":{"name":"Genome informatics. International Conference on Genome Informatics","volume":"2008 1","pages":"218-29"},"PeriodicalIF":0.0,"publicationDate":"2010-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82496330","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Comparison of gene expression profiles produced by CAGE, illumina microarray and real time RT-PCR.","authors":"André Fujita, Masao Nagasaki, Seiya Imoto, Ayumu Saito, Emi Ikeda, Teppei Shimamura, Rui Yamaguchi, Yoshihide Hayashizaki, Satoru Miyano","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Several technologies are currently used for gene expression profiling, such as Real Time RT-PCR, microarray and CAGE (Cap Analysis of Gene Expression). CAGE is a recently developed method for constructing transcriptome maps and it has been successfully applied to analyzing gene expressions in diverse biological studies. The principle of CAGE has been developed to address specific issues such as determination of transcriptional starting sites, the study of promoter regions and identification of new transcripts. Here, we present both quantitative and qualitative comparisons among three major gene expression quantification techniques, namely: CAGE, illumina microarray and Real Time RT-PCR, by showing that the quantitative values of each method are not interchangeable, however, each of them has unique characteristics which render all of them essential and complementary. Understanding the advantages and disadvantages of each technology will be useful in selecting the most appropriate technique for a determined purpose.</p>","PeriodicalId":73143,"journal":{"name":"Genome informatics. International Conference on Genome Informatics","volume":"24 ","pages":"56-68"},"PeriodicalIF":0.0,"publicationDate":"2010-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"30252336","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Annotating gene functions with integrative spectral clustering on microarray expressions and sequences.","authors":"Limin Li, Motoki Shiga, Wai-Ki Ching, Hiroshi Mamitsuka","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Annotating genes is a fundamental issue in the post-genomic era. A typical procedure for this issue is first clustering genes by their features and then assigning functions of unknown genes by using known genes in the same cluster. A lot of genomic information are available for this issue, but two major types of data which can be measured for any gene are microarray expressions and sequences, both of which however have their own flaws. Thus a natural and promising approach for gene annotation is to integrate these two data sources, especially in terms of their costs to be optimized in clustering. We develop an efficient gene annotation method with three steps containing spectral clustering over the integrated cost, based on the idea of network modularity. We rigorously examined the performance of our proposed method from three different viewpoints. All experimental results indicate the performance advantage of our method over possible clustering/classification-based approaches of gene function annotation, using expressions and/or sequences.</p>","PeriodicalId":73143,"journal":{"name":"Genome informatics. International Conference on Genome Informatics","volume":"22 ","pages":"95-120"},"PeriodicalIF":0.0,"publicationDate":"2010-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"28785610","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"New kernel methods for phenotype prediction from genotype data.","authors":"Ritsuko Onuki, Tetsuo Shibuya, Minoru Kanehisa","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Phenotype prediction from genotype data is one of the most important issues in computational genetics. In this work, we propose a new kernel (i.e., an SVM: Support Vector Machine) method for phenotype prediction from genotype data. In our method, we first infer multiple suboptimal haplotype candidates from each genotype by using the HMM (Hidden Markov Model), and the kernel matrix is computed based on the predicted haplotype candidates and their emission probabilities from the HMM. We validated the performance of our method through experiments on several datasets: One is an artificially constructed dataset via a program GeneArtisan, others are a real dataset of the NAT2 gene from the international HapMap project, and a real dataset of genotypes of diseased individuals. The experiments show that our method is superior to ordinary naive kernel methods (i.e., not based on haplotype prediction), especially in cases of strong LD (linkage disequilibrium).</p>","PeriodicalId":73143,"journal":{"name":"Genome informatics. International Conference on Genome Informatics","volume":"22 ","pages":"132-41"},"PeriodicalIF":0.0,"publicationDate":"2010-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"28785612","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A state space representation of VAR models with sparse learning for dynamic gene networks.","authors":"Kaname Kojima, Rui Yamaguchi, Seiya Imoto, Mai Yamauchi, Masao Nagasaki, Ryo Yoshida, Teppei Shimamura, Kazuko Ueno, Tomoyuki Higuchi, Noriko Gotoh, Satoru Miyano","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>We propose a state space representation of vector autoregressive model and its sparse learning based on L1 regularization to achieve efficient estimation of dynamic gene networks based on time course microarray data. The proposed method can overcome drawbacks of the vector autoregressive model and state space model; the assumption of equal time interval and lack of separation ability of observation and systems noises in the former method and the assumption of modularity of network structure in the latter method. However, in a simple implementation the proposed model requires the calculation of large inverse matrices in a large number of times during parameter estimation process based on EM algorithm. This limits the applicability of the proposed method to a relatively small gene set. We thus introduce a new calculation technique for EM algorithm that does not require the calculation of inverse matrices. The proposed method is applied to time course microarray data of lung cells treated by stimulating EGF receptors and dosing an anticancer drug, Gefitinib. By comparing the estimated network with the control network estimated using non-treated lung cells, perturbed genes by the anticancer drug could be found, whose up- and down-stream genes in the estimated networks may be related to side effects of the anticancer drug.</p>","PeriodicalId":73143,"journal":{"name":"Genome informatics. International Conference on Genome Informatics","volume":"22 ","pages":"56-68"},"PeriodicalIF":0.0,"publicationDate":"2010-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"28785607","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Formal representation of the high osmolarity glycerol pathway in yeast.","authors":"C. Kühn, K. V. S. Prasad, E. Klipp, P. Gennemark","doi":"10.1142/9781848165786_0007","DOIUrl":"https://doi.org/10.1142/9781848165786_0007","url":null,"abstract":"The high osmolarity glycerol (HOG) signalling system in yeast belongs to the class of Mitogen Activated Protein Kinase (MAPK) pathways that are found in all eukaryotic organisms. It includes at least three scaffold proteins that form complexes, and involves reactions that are strictly dependent on the set of species bound to a certain complex. The scaffold proteins lead to a combinatorial increase in the number of possible states. To date, representations of the HOG pathway have used simplifying assumptions to avoid this combinatorial problem. Such assumptions are hard to make and may obscure or remove essential properties of the system. This paper presents a detailed generic formal representation of the HOG system without such assumptions, showing the molecular interactions known from the literature. The model takes complexes into account, and summarises existing knowledge in an unambiguous and detailed representation. It can thus be used to anchor discussions about the HOG system. In the commonly used Systems Biology Markup Language (SBML), such a model would need to explicitly enumerate all state variables. The Kappa modelling language which we use supports representation of complexes without such enumeration. To conclude, we compare Kappa with a few other modelling languages and software tools that could also be used to represent and model the HOG system.","PeriodicalId":73143,"journal":{"name":"Genome informatics. International Conference on Genome Informatics","volume":"103 1","pages":"69-83"},"PeriodicalIF":0.0,"publicationDate":"2010-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80928254","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Michael Fernandez, Satoshi Fujii, Hidetoshi Kono, Akinori Sarai
{"title":"Evaluation of DNA intramolecular interactions for nucleosome positioning in yeast.","authors":"Michael Fernandez, Satoshi Fujii, Hidetoshi Kono, Akinori Sarai","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>We calculated intramolecular interaction energies of DNA by threading DNA sequences around crystal structures of nucleosomes. The strength of the intramolecular energy oscillations at frequency approximately 10 bps for dinucleotides was in agreement with previous nucleosome models. The intramolecular energy calculated along yeast genome positively correlated with nucleosome positioning experimentally measured.</p>","PeriodicalId":73143,"journal":{"name":"Genome informatics. International Conference on Genome Informatics","volume":"23 1","pages":"13-20"},"PeriodicalIF":0.0,"publicationDate":"2009-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"28734938","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Comparative analysis of aerobic and anaerobic prokaryotes to identify correlation between oxygen requirement and gene-gene functional association patterns.","authors":"Yaming Lin, Hongwei Wu","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Activities of prokaryotes are pivotal in shaping the environment, and are also greatly influenced by the environment. With the substantial progress in genome and metagenome sequencing and the about-to-be-standardized ecological context information, environment-centric comparative genomics will complement species-centric comparative genomics, illuminating how environments have shaped and maintained prokaryotic diversities. In this paper we report our preliminary studies on the association analysis of a particular duo of genomic and ecological traits of prokaryotes--gene-gene functional association patterns vs. oxygen requirement conditions. We first establish a stochastic model to describe gene arrangements on chromosomes, based on which the functional association between genes are quantified. The gene-gene functional association measures are validated using biological process ontology and KEGG pathway annotations. Student's t-tests are then performed on the aerobic and anaerobic organisms to identify those gene pairs that exhibit different functional association patterns in the two different oxygen requirement conditions. As it is difficult to design and conduct biological experiments to validate those genome-environment association relationships that have resulted from long-term accumulative genome-environment interactions, we finally conduct computational validations to determine whether the oxygen requirement condition of an organism is predictable based on gene-gene functional association patterns. The reported study demonstrates the existence and significance of the association relationships between certain gene-gene functional association patterns and oxygen requirement conditions of prokaryotes, as well as the effectiveness of the adopted methodology for such association analysis.</p>","PeriodicalId":73143,"journal":{"name":"Genome informatics. International Conference on Genome Informatics","volume":"23 1","pages":"72-84"},"PeriodicalIF":0.0,"publicationDate":"2009-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"28734943","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}