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Evolution of olfactory receptor genes in East Asian loaches

Zoological Studies 2009年第2期48卷 223-237页

作者： Wang, Daryi Wang, Tzi-Yuan Weng, Li-Chuan Emori, Yasufumi Tzeng, Chyng-Shyan Li, Wen-Hsiung Biodiversity Research Center Academia Sinica Taipei 115 Taiwan Genomics Research Center Academia Sinica Taipei 115 Taiwan Department of Biophysics and Biochemistry Graduate School of Science University of Tokyo Bunkyo Tokyo 113-0033 7-3-1 Hongo Japan Undergraduate Program for Bioinformatics and System Biology University of Tokyo Bunkyo Tokyo 113-0033 7-3-1 Hongo Japan Institute of Bioinformatics and Structural Biology Department of Life Sciences National Tsing Hua University Hsinchu 300 Taiwan

Daryi Wang, Tzi-Yuan Wang, Li-Chuan Weng, Yasufumi Emori, Chyng-Shyan Tzeng, and Wen-Hsiung Li (2009) Evolution of olfactory receptor genes in East Asian loaches. Zoological Studies 48(2): 223-237. It is well known that fish have fewer olfactory receptor (OR) genes than mammals do. In order to investigate the divergence of and evolutionary changes in OR genes in fish, 2 loach OR gene families (D1/3 and D32) from Taiwanese and Chinese populations of 2 species (Misgurnus anguillicaudatus and Paramisgurnus dabryanus) were analyzed. We found duplications in both D1/3 and D32 that had accumulated after the separation of the island of Taiwan from the Asian mainland ~5 million yrs ago. The accumulation of duplicate copies in a relatively short time suggests that gaining extra copies of OR genes may have been selectively advantageous for adapting to local environments. On the other hand, the loss of some OR genes in the 2 species in Taiwan may reflect loss of selective constraints on some OR genes. Moreover, unlike the situation in mammals in which pseudogenes are found in each family, pseudogenes are clustered in an expanding gene family in P. dabryanus in Taiwan. The presence of pseudogenes and the limited number of functional OR genes in fish suggest that fish do not need a large number of OR genes. Finally, the dynamic changes in OR gene number and the possible explanation for a lower OR gene number in fish are discussed. http://***/Journals/48.2/***.

关键词： Adaptation Misgurnus anguillicaudatus Multigene family Olfaction Paramisgurnus dabryanus

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PSLDoc: Protein subcellular localization prediction based on gapped-dipeptides and probabilistic latent semantic analysis

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Proteins: Structure, Function and Genetics 2008年第2期72卷 693-710页

作者： Chang, Jia-Ming Su, Emily Chia-Yu Lo, Allan Chiu, Hua-Sheng Sung, Ting-Yi Hsu, Wen-Lian Bioinformatics Lab. Institute of Information Science Acaderma Sinica Taipei Taiwan Bioinformatics Program Taiwan International Graduate Program Academia Sinica Taipei Taiwan Institute of Bioinformatics National Chiao Tung University Hsinchu Taiwan Department of Life Sciences National Tsing Hua University Hsinchu Taiwan Institute of Information Science Academia Sinica Nankang Taipei 128 Academia Road Taiwan

Prediction of protein subcellular localization (PSL) is important for genome annotation, protein function prediction, and drug discovery. Many computational approaches for PSL prediction based on protein sequences have been proposed in recent years for Gram-negative bacteria. We present PSLDoc, a method based on gapped-dipeptides and probabilistic latent semantic analysis (PLSA) to solve this problem. A protein is considered as a term string composed by gapped-dipeptides, which are defined as any two residues separated by one or more positions. The weighting scheme of gapped-dipeptides is calculated according to a position specific score matrix, which includes sequence evolutionary information. Then, PLSA is applied for feature reduction, and reduced vectors are input to five one-versus-rest support vector machine classifiers. The localization site with the highest probability is assigned as the final prediction. It has been reported that there is a strong correlation between sequence homology and subcellular localization (Nair and Rost, Protein Sci 2002;11:2836-2847;Yu et al., Proteins 2006;64:643-651). To properly evaluate the performance of PSLDoc, a target protein can be classified into low- or high-homology data sets. PSLDoc's overall accuracy of low- and high-homology data sets reaches 86.84% and 98.21%, respectively, and it compares favorably with that of CELLO II (Yu et al, Proteins 2006;64:643-651). In addition, we set a confidence threshold to achieve a high precision at specified levels of recall rates. When the confidence threshold is set at 0.7, PSLDoc achieves 97.89% in precision which is considerably better than that of PSORTb v.2.0 (Gardy et al., bioinformatics 2005;21:617-623). Our approach demonstrates that the specific feature representation for proteins can be successfully applied to the prediction of protein subcellular localization and improves prediction accuracy. Besides, because of the generality of the representation, our method can be exte

关键词： Document classification Gapped-dipeptides Probabilistic latent semantic analysis Protein subcellular localization Support vector machines Vector space model

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Large-scale analysis of human heavy chain V(D)J recombination patterns

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Immunome Research 2008年第1期4卷 1-10页

作者： Volpe, Joseph M Kepler, Thomas B Center for Computational Immunology Duke University Durham NC United States Department of Immunology Duke Univeristy Medical Center Durham NC United States Department of Biostatistics and Bioinformatics Duke Univeristy Medical Center Durham NC United States Institute of Statistics and Decision Sciences Duke Univeristy Durham NC United States Computational Biology and Bioinformatics Graduate Program Institute for Genome Sciences and Policy Duke Univeristy Durham NC United States

Background. The processes involved in the somatic assembly of antigen receptor genes are unique to the immune system and are driven largely by random events. Subtle biases, however, may exist and provide clues to the molecular mechanisms involved in their assembly and selection. Large-scale efforts to provide baseline data about the genetic characteristics of immunoglobulin (Ig) genes and the mechanisms involved in their assembly have recently become possible due to the rapid growth of genetic databases. Results. We gathered and analyzed nearly 6,500 productive human Ig heavy chain genes and compared them with 325 non-productive Ig genes that were originally rearranged out of frame and therefore incapable of being biased by selection. We found evidence for differences in n-nucleotide tract length distributions which have interesting interpretations for the mechanisms involved in n-nucleotide polymerization. Additionally, we found striking statistical evidence for pairing preferences among D and J segments. We present a statistical model to support our hypothesis that these pairing biases are due to multiple sequential D-to-J rearrangements. Conclusion. We present here the most precise estimates of gene segment usage frequencies currently available along with analyses regarding n-nucleotide distributions and D-J segment pair preferences. Additionally, we provide the first statistical evidence that sequential D-J recombinations occur at the human heavy chain locus during B-cell ontogeny with an approximate frequency of 20%.

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Study on the immobilization of Ni-NTA and NTA on PMMA substrate base

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Key Engineering Materials 2008年 381-382卷 357-360页

作者： Chong, W.S. Kim, G.B. Hong, C.U. Department of Biomedical Engineering Graduate School Chonbuk National University Duckjin-Dong Jeonju Jeonbuk 561-756 Korea Republic of Education Program for 21st Century Chonbuk National University Research Institute of Clinical Medicine Duckjin-Dong Jeonju Jeonbuk 561-756 Korea Republic of Division of Bionics and Bioinformatics Collage of Engineering Chonbuk National University Duckjin-Dong Jeonju Jeonbuk 561-756 Korea Republic of

In this study, we attempts to develop a sensing method to detect mismatched DNA in order to diagnose cancer. The sensing method will be developed to use for early diagnosis of cancer. Thus, protein immobilization was applied on the surface of the sensor in order to facilitate the detection of mismatched DNA. This method was designed to achieve the Ni-His-Tag to selectively bond with MutS, which has a covalent bond with the His-Tag, by using Ni-NTA. This method is troublesome because it involves a number of repeated composition processes. This method need gold surface to immobilize NTA (nitrotriamino acid). But this process is very complicated and expensive cost. Therefore, we try to immobilize NTA using PMMA (poly methyl methacrylate) polymer in this research to improve this method. In this study revealed that we could directly immobilize the NTA to the PMMA substrate not used Gold substrate. Also, we could directly immobilize the MutS to the NTA using the EDC solution. In addition, we can expect that the mismatched DNA can be detected from the results.

关键词： Proteins

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Using a literature-based NMF model for discovering gene functional relationships

Using a literature-based NMF model for discovering gene func...

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IEEE International Conference on bioinformatics and Biomedicine Workshops (BIBMW)

作者： Elina Tjioe Michael Berry Ramin Homayouni Genome Science and Technology Graduate School University of Tennessee Knoxville TN USA Department of Electrical Engineering and Computer Science University of Tennessee Knoxville TN USA Bioinformatics Program Department of Biology University of Memphis Memphis TN USA

The rapid growth of the biomedical literature and genomic information presents a major challenge for determining the functional relationships among genes. In this study, we develop a Web-based bioinformatics software environment called FAUN or feature annotation using nonnegative matrix factorization (NMF) to facilitate both the discovery and classification of functional relationships among genes. Both the computational complexity and parameterization of NMF for processing gene sets are discussed. We tested FAUN on three manually constructed gene document collections, and then used it to analyze several microarray-derived gene sets obtained from studies of the developing cerebellum in normal and mutant mice. FAUN provides utilities for collaborative knowledge discovery and identification of new gene relationships from text streams and repositories (e.g., MEDLINE). It is particularly useful for the validation and analysis of gene associations suggested by microarray experimentation.

关键词： bioinformatics Genomics Data mining Matrix decomposition Large scale integration Feature extraction Iterative methods Biological system modeling Computer science Computational biology

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Unexpected failure rates for modular assembly of engineered zinc fingers (vol 5, pg 374, 2008)

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NATURE METHODS 2008年第6期5卷 575-575页

作者： Ramirez, Cherie L. Foley, Jonathan E. Wright, David A. Mueller-Lerch, Felix Rahman, Shamim H. Cornu, Tatjana I. Winfrey, Ronnie J. Sander, Jeffry D. Fu, Fengli Townsend, Jeffrey A. Cathomen, Toni Voytas, Daniel F. Joung, J. Keith Molecular Pathology Unit Center for Cancer Research and Center for Computational and Integrative Biology 149 13th Street Room 7132 Massachusetts General Hospital Charlestown USA Division of Medical Sciences Biological and Biomedical Sciences Program Harvard Medical School Boston USA Department of Genetics Development and Cell Biology Iowa State University 1035A Roy J. Carver Co-Lab Ames USA Charité Medical School Institute of Virology Hindenburgdamm 27 Berlin Germany Interdepartmental Graduate Program in Bioinformatics and Computational Biology 2114 Molecular Biology Building Iowa State University Ames USA Department of Pathology Harvard Medical School Boston USA

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Study of equilibrium sense improvement displaying visual information

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Key Engineering Materials 2008年 381-382卷 369-372页

作者： Kim, G.B. Jeong, S.H. Chong, W.S. Kang, H.S. Kim, S.J. Kim, M.H. Hwang, J.W. Hong, C.U. Education Program for 21st Century Chonbuk National University Research Institute of Clinical Medicine Duckjin-Dong Jeonju Chonbuk 561-756 Korea Republic of Department of Computer Engineering Graduate School Chonbuk National University Duckjin-Dong Jeonju Chonbuk 561-756 Korea Republic of Department of Biomedical Engineering Graduate School Chonbuk National University Duckjin-Dong Jeonju Chonbuk 561-756 Korea Republic of Department of Pharmacology College of Veterinary Medicine Chonbuk National University Duckjin-Dong Jeonju Chonbuk 561-756 Korea Republic of Department of Bio and Applied Chemistry Iksan National College Ma-Dong Iksan Chonbuk 570-752 Korea Republic of Department of Thoracic and Cardiovascular Surgery Chonbuk National University Medical Schools Duckjin-Dong Jeonju Chonbuk 561-756 Korea Republic of Collage of Engineering Chonbuk National University Duckjin-Dong Jeonju Chonbuk 561-756 Korea Republic of Division of Bionics and Bioinformatics Collage of Engineering Chonbuk National University Duckjin-Dong Jeonju Chonbuk 561-756 Korea Republic of

The effectiveness of the visual feedback to improve ability with the sense and muscular strength of human in our bicycle system was quantitatively verified in our study. Experiments were performed to find the factors related to the training of equilibrium sense. The subjects consisted of young and the aged and the group of young people was compared against the group of the aged. We investigated three different training modes, non-visual feedback (NVF), visual feedback of the weight (VFW), and visual feedback of the center of pressure (VFC) and measured the riding time and speed, the weight shift, and the center of pressure (COP) for twenties and seventies. The results showed that the running capability of the young and the aged became much better after repeated training. In addition, it was found out that the ability to control postural balance and the capability of equilibrium sense were improved with the presentation of the visual feedback information. These results will be effective in the diagnosis of equilibrium sense and vestibular function with the aged.

关键词： Feedback

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eXpanda: An integrated platform for network analysis and visualization

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In Silico Biology 2007年第2期7卷 141-144页

作者： Negishi, Yoshiteru Nakamura, Hiroyuki Yachie, Nozomu Saito, Rintaro Tomita, Masaru Institute for Advanced Biosciences Keio University Fujisawa 252-8520 Japan Bioinformatics Program Graduate School of Media and Governance Keio University Fujisawa 252-8520 Japan Department of Environmental Information Keio University Fujisawa 252-8520 Japan

Analysis and visualization of biological networks, such as protein-protein and protein-DNA interactions, are crucially important toward obtaining a thorough understanding of living systems. Here, we present an integrative software platform, eXpanda, which enables an analysis of a very broad range of biological networks, with a special focus on the extraction of characteristic topologies which potentially function as units in the networks. eXpanda is provided as a Perl library which gives full-automatic connections to various biological databases via a Perl programmable interface and can perform topological analysis based on graph theory. The results of these analyses are visualizable by vector graphics. eXpanda is under GNU General Public License. Software package, detailed documentations, source codes, and some sample scripts are downloadable at http://***/expanda/. © 2007 IOS Press. All rights reserved.

关键词： Interactome Network analysis Network visualization Perl library Scalable Vector Graphics (SVG)

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Structural characterization of RNA-binding sites of proteins: Preliminary results

Structural characterization of RNA-binding sites of proteins...

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IEEE International Conference on bioinformatics and Biomedicine Workshops (BIBMW)

作者： Fadi Towfic David C. Gemperline Cornelia Caragea Feihong Wu Drena Dobbs Vasant Honavar Bioinformatics and Computational Biology Graduate Program Iowa State University Ames IA USA Department of Biology Department of Chemistry Carthage College Kenosha WI USA Department of Computer Science Iowa State University Ames IA USA Department of Genetics Development and Cell Biology Bioinformatics and Computational Biology Graduate Program Iowa State University Ames IA USA Department of Computer Science Bioinformatics and Computational Biology Graduate Program Iowa State University Ames IA USA

We explore whether protein-RNA interfaces differ from non-interfaces in terms of their structural features and whether structural features vary according to the type of the bound RNA (e.g., mRNA, siRNA...etc), using a non-redundant dataset of 147 protein chains extracted from protein-RNA complexes in the protein data bank. Our analysis of surface roughness, solid angle and CX value of amino acid residues for each of the protein chains in the dataset shows that: The protein-RNA interface residues tend to be protruding compared to non-interface residues and tend to have higher surface roughness and exhibit moderately convex or concave solid angles. Furthermore, the protein chains in protein-RNA interfaces that contain Viral RNA and rRNA significantly differ from those that contain dsRNA, mRNA siRNA, snRNA, SRP RNA and tRNA with respect to their CX values. The results of this analysis sug gests the possibility of using such structural features to reliably identify protein-RNA interface residues when the structure of the protein is available but the structures of complexes formed by the protein with RNA are not.

关键词： RNA Protein engineering Biology computing Amino acids bioinformatics Computer interfaces Rough surfaces Surface roughness Solids Machine learning

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A kinetic model for calcium dynamics in RAW 264.7 cells: 1. Mechanisms, parameters, and subpopulational variability

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Biophysical Journal 2007年第3期93卷 709-728页

作者： Maurya, Mano Ram Subramaniam, Shankar Department of Bioengineering University of California San Diego CA United States Department of Chemistry and Biochemistry University of California San Diego CA United States Graduate Program in Bioinformatics University of California San Diego CA United States Dept. of Bioengineering University of California San Diego San Diego CA 92093-0412 9500 Gilman Dr. United States

Calcium (Ca2+) is an important second messenger and has been the subject of numerous experimental measurements and mechanistic studies in intracellular signaling. Calcium profile can also serve as a useful cellular ph...

Calcium (Ca²⁺) is an important second messenger and has been the subject of numerous experimental measurements and mechanistic studies in intracellular signaling. Calcium profile can also serve as a useful cellular phenotype. Kinetic models of calcium dynamics provide quantitative insights into the calcium signaling networks. We report here the development of a complex kinetic model for calcium dynamics in RAW 264.7 cells stimulated by the C5a ligand. The model is developed using the vast number of measurements of in vivo calcium dynamics carried out in the Alliance for Cellular Signaling (AfCS) Laboratories. Ligand binding, phospholipase C-β (PLC-β) activation, inositol 1,4,5-trisphosphate (IP3) receptor (IP3R) dynamics, and calcium exchange with mitochondria and extracellular matrix have all been incorporated into the model. The experimental data include data from both native and knockdown cell lines. Subpopulational variability in measurements is addressed by allowing nonkinetic parameters to vary across datasets. The model predicts temporal response of Ca²⁺ concentration for various doses of C5a under different initial conditions. The optimized parameters for IP3R dynamics are in agreement with the legacy data. Further, the half-maximal effect concentration of C5a and the predicted dose response are comparable to those seen in AfCS measurements. Sensitivity analysis shows that the model is robust to parametric perturbations. © 2007 by the Biophysical Society.

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