@article {49724, title = {Phenotype-based cell-specific metabolic modeling reveals metabolic liabilities of cancer.}, journal = {Elife}, volume = {3}, year = {2014}, month = {2014}, abstract = {

Utilizing molecular data to derive functional physiological models tailored for specific cancer cells can facilitate the use of individually tailored therapies. To this end we present an approach termed PRIME for generating cell-specific genome-scale metabolic models (GSMMs) based on molecular and phenotypic data. We build >280 models of normal and cancer cell-lines that successfully predict metabolic phenotypes in an individual manner. We utilize this set of cell-specific models to predict drug targets that selectively inhibit cancerous but not normal cell proliferation. The top predicted target, MLYCD, is experimentally validated and the metabolic effects of MLYCD depletion investigated. Furthermore, we tested cell-specific predicted responses to the inhibition of metabolic enzymes, and successfully inferred the prognosis of cancer patients based on their PRIME-derived individual GSMMs. These results lay a computational basis and a counterpart experimental proof of concept for future personalized metabolic modeling applications, enhancing the search for novel selective anticancer therapies.

}, keywords = {algorithms, Antineoplastic Agents, Biomarkers, Tumor, Carboxy-Lyases, Cell Line, Tumor, Cell Proliferation, Citric Acid Cycle, Fatty Acids, Gene Knockdown Techniques, Genome, Human, HUMANS, Lymphocytes, Models, Biological, Neoplasms, Oxidation-Reduction, PHENOTYPE, Precision Medicine}, issn = {2050-084X}, doi = {10.7554/eLife.03641}, author = {Yizhak, Keren and Gaude, Edoardo and Le D{\'e}v{\'e}dec, Sylvia and Waldman, Yedael Y and Stein, Gideon Y and van de Water, Bob and Frezza, Christian and Ruppin, Eytan} } @article {49572, title = {Sailfish enables alignment-free isoform quantification from RNA-seq reads using lightweight algorithms.}, volume = {32}, year = {2014}, month = {2014 May}, pages = {462-4}, abstract = {

We introduce Sailfish, a computational method for quantifying the abundance of previously annotated RNA isoforms from RNA-seq data. Because Sailfish entirely avoids mapping reads, a time-consuming step in all current methods, it provides quantification estimates much faster than do existing approaches (typically 20 times faster) without loss of accuracy. By facilitating frequent reanalysis of data and reducing the need to optimize parameters, Sailfish exemplifies the potential of lightweight algorithms for efficiently processing sequencing reads.

}, keywords = {algorithms, Brain Chemistry, Computational Biology, HUMANS, Models, Biological, RNA Isoforms, Sequence Analysis, RNA, software}, issn = {1546-1696}, doi = {10.1038/nbt.2862}, author = {Patro, Rob and Mount, Stephen M and Kingsford, Carl} } @article {49728, title = {Predicting selective drug targets in cancer through metabolic networks.}, journal = {Mol Syst Biol}, volume = {7}, year = {2011}, month = {2011}, pages = {501}, abstract = {

The interest in studying metabolic alterations in cancer and their potential role as novel targets for therapy has been rejuvenated in recent years. Here, we report the development of the first genome-scale network model of cancer metabolism, validated by correctly identifying genes essential for cellular proliferation in cancer cell lines. The model predicts 52 cytostatic drug targets, of which 40\% are targeted by known, approved or experimental anticancer drugs, and the rest are new. It further predicts combinations of synthetic lethal drug targets, whose synergy is validated using available drug efficacy and gene expression measurements across the NCI-60 cancer cell line collection. Finally, potential selective treatments for specific cancers that depend on cancer type-specific downregulation of gene expression and somatic mutations are compiled.

}, keywords = {Cell Line, Tumor, Cell Proliferation, Computational Biology, Cytostatic Agents, Down-Regulation, Drug Delivery Systems, Gene Expression Regulation, Neoplastic, HUMANS, Metabolic Networks and Pathways, Models, Biological, Neoplasms, RNA, Small Interfering}, issn = {1744-4292}, doi = {10.1038/msb.2011.35}, author = {Folger, Ori and Jerby, Livnat and Frezza, Christian and Gottlieb, Eyal and Ruppin, Eytan and Shlomi, Tomer} } @article {38161, title = {Comparative genomics of emerging human ehrlichiosis agents}, journal = {PLoS geneticsPLoS genetics}, volume = {2}, year = {2006}, note = {http://www.ncbi.nlm.nih.gov/pubmed/16482227?dopt=Abstract}, type = {10.1371/journal.pgen.0020021}, abstract = {Anaplasma (formerly Ehrlichia) phagocytophilum, Ehrlichia chaffeensis, and Neorickettsia (formerly Ehrlichia) sennetsu are intracellular vector-borne pathogens that cause human ehrlichiosis, an emerging infectious disease. We present the complete genome sequences of these organisms along with comparisons to other organisms in the Rickettsiales order. Ehrlichia spp. and Anaplasma spp. display a unique large expansion of immunodominant outer membrane proteins facilitating antigenic variation. All Rickettsiales have a diminished ability to synthesize amino acids compared to their closest free-living relatives. Unlike members of the Rickettsiaceae family, these pathogenic Anaplasmataceae are capable of making all major vitamins, cofactors, and nucleotides, which could confer a beneficial role in the invertebrate vector or the vertebrate host. Further analysis identified proteins potentially involved in vacuole confinement of the Anaplasmataceae, a life cycle involving a hematophagous vector, vertebrate pathogenesis, human pathogenesis, and lack of transovarial transmission. These discoveries provide significant insights into the biology of these obligate intracellular pathogens.}, keywords = {Animals, Biotin, DNA Repair, Ehrlichia, Ehrlichiosis, Genome, Genomics, HUMANS, Models, Biological, Phylogeny, Rickettsia, Ticks}, author = {Dunning Hotopp, Julie C. and Lin, Mingqun and Madupu, Ramana and Crabtree, Jonathan and Angiuoli, Samuel V. and Eisen, Jonathan A. and Eisen, Jonathan and Seshadri, Rekha and Ren, Qinghu and Wu, Martin and Utterback, Teresa R. and Smith, Shannon and Lewis, Matthew and Khouri, Hoda and Zhang, Chunbin and Niu, Hua and Lin, Quan and Ohashi, Norio and Zhi, Ning and Nelson, William and Brinkac, Lauren M. and Dodson, Robert J. and Rosovitz, M. J. and Sundaram, Jaideep and Daugherty, Sean C. and Davidsen, Tanja and Durkin, Anthony S. and Gwinn, Michelle and Haft, Daniel H. and J. Selengut and Sullivan, Steven A. and Zafar, Nikhat and Zhou, Liwei and Benahmed, Faiza and Forberger, Heather and Halpin, Rebecca and Mulligan, Stephanie and Robinson, Jeffrey and White, Owen and Rikihisa, Yasuko and Tettelin, Herv{\'e}} } @article {49640, title = {Trypanosoma cruzi mitochondrial maxicircles display species- and strain-specific variation and a conserved element in the non-coding region.}, journal = {BMC Genomics}, volume = {7}, year = {2006}, month = {2006}, pages = {60}, abstract = {

BACKGROUND: The mitochondrial DNA of kinetoplastid flagellates is distinctive in the eukaryotic world due to its massive size, complex form and large sequence content. Comprised of catenated maxicircles that contain rRNA and protein-coding genes and thousands of heterogeneous minicircles encoding small guide RNAs, the kinetoplast network has evolved along with an extreme form of mRNA processing in the form of uridine insertion and deletion RNA editing. Many maxicircle-encoded mRNAs cannot be translated without this post-transcriptional sequence modification.

RESULTS: We present the complete sequence and annotation of the Trypanosoma cruzi maxicircles for the CL Brener and Esmeraldo strains. Gene order is syntenic with Trypanosoma brucei and Leishmania tarentolae maxicircles. The non-coding components have strain-specific repetitive regions and a variable region that is unique for each strain with the exception of a conserved sequence element that may serve as an origin of replication, but shows no sequence identity with L. tarentolae or T. brucei. Alternative assemblies of the variable region demonstrate intra-strain heterogeneity of the maxicircle population. The extent of mRNA editing required for particular genes approximates that seen in T. brucei. Extensively edited genes were more divergent among the genera than non-edited and rRNA genes. Esmeraldo contains a unique 236-bp deletion that removes the 5{\textquoteright}-ends of ND4 and CR4 and the intergenic region. Esmeraldo shows additional insertions and deletions outside of areas edited in other species in ND5, MURF1, and MURF2, while CL Brener has a distinct insertion in MURF2.

CONCLUSION: The CL Brener and Esmeraldo maxicircles represent two of three previously defined maxicircle clades and promise utility as taxonomic markers. Restoration of the disrupted reading frames might be accomplished by strain-specific RNA editing. Elements in the non-coding region may be important for replication, transcription, and anchoring of the maxicircle within the kinetoplast network.

}, keywords = {Amino Acid Sequence, Animals, Animals, Inbred Strains, Base Composition, Conserved Sequence, DNA, Kinetoplast, Frameshifting, Ribosomal, Gene Deletion, Gene Order, Genetic Variation, Leishmania, Models, Biological, Molecular Sequence Data, Muscle Proteins, NADH Dehydrogenase, Open Reading Frames, Regulatory Elements, Transcriptional, RNA Editing, Sequence Homology, Amino Acid, Species Specificity, Trypanosoma brucei brucei, Trypanosoma cruzi, Ubiquitin-Protein Ligases, Untranslated Regions}, issn = {1471-2164}, doi = {10.1186/1471-2164-7-60}, author = {Westenberger, Scott J and Cerqueira, Gustavo C and El-Sayed, Najib M and Zingales, Bianca and Campbell, David A and Sturm, Nancy R} } @article {49562, title = {MCMC-based particle filtering for tracking a variable number of interacting targets.}, volume = {27}, year = {2005}, month = {2005 Nov}, pages = {1805-19}, abstract = {

We describe a particle filter that effectively deals with interacting targets--targets that are influenced by the proximity and/or behavior of other targets. The particle filter includes a Markov random field (MRF) motion prior that helps maintain the identity of targets throughout an interaction, significantly reducing tracker failures. We show that this MRF prior can be easily implemented by including an additional interaction factor in the importance weights of the particle filter. However, the computational requirements of the resulting multitarget filter render it unusable for large numbers of targets. Consequently, we replace the traditional importance sampling step in the particle filter with a novel Markov chain Monte Carlo (MCMC) sampling step to obtain a more efficient MCMC-based multitarget filter. We also show how to extend this MCMC-based filter to address a variable number of interacting targets. Finally, we present both qualitative and quantitative experimental results, demonstrating that the resulting particle filters deal efficiently and effectively with complicated target interactions.

}, keywords = {algorithms, Animals, Artificial Intelligence, Computer simulation, HUMANS, Image Enhancement, Image Interpretation, Computer-Assisted, Information Storage and Retrieval, Markov chains, Models, Biological, Models, Statistical, Monte Carlo Method, Motion, Movement, Pattern Recognition, Automated, Subtraction Technique, Video Recording}, issn = {0162-8828}, doi = {10.1109/TPAMI.2005.223}, author = {Khan, Zia and Balch, Tucker and Dellaert, Frank} } @article {49563, title = {An outdoor 3-D visual tracking system for the study of spatial navigation and memory in rhesus monkeys.}, volume = {37}, year = {2005}, month = {2005 Aug}, pages = {453-63}, abstract = {

Previous studies of the navigational abilities of nonhuman primates have largely been limited to what could be described by a human observer with a pen and paper. Consequently, we have developed a system that uses a pair of cameras to automatically obtain the three-dimensional trajectory of rhesus monkeys performing an outdoor spatial navigation and memory task. The system provides trajectories, path length, speed, and other variables that would be impossible for an unaided observer to note. From trajectory data, we computed and validated a path-length measurement. We use this measurement to compare the navigation abilities of several animals. In addition, we provide quantitative data on the accuracy of a method for automatic behavior detection. Currently, the system is being used to examine the sex differences in spatial navigation of rhesus monkeys. We expect that measures derived from the trajectory data will reveal strategies used by animals to solve spatial problems.

}, keywords = {Animals, Behavior, Animal, Macaca mulatta, Memory, Models, Biological, Space Perception, Visual Perception}, issn = {1554-351X}, author = {Khan, Zia and Herman, Rebecca A and Wallen, Kim and Balch, Tucker} }