{"title":"Prediction of signal peptides using bio-basis function neural networks and decision trees.","authors":"Ateesh Sidhu, Zheng Rong Yang","doi":"10.2165/00822942-200605010-00002","DOIUrl":"https://doi.org/10.2165/00822942-200605010-00002","url":null,"abstract":"<p><p>Signal peptide identification is of immense importance in drug design. Accurate identification of signal peptides is the first critical step to be able to change the direction of the targeting proteins and use the designed drug to target a specific organelle to correct a defect. Because experimental identification is the most accurate method, but is expensive and time-consuming, an efficient and affordable automated system is of great interest. In this article, we propose using an adapted neural network, called a bio-basis function neural network, and decision trees for predicting signal peptides. The bio-basis function neural network model and decision trees achieved 97.16% and 97.63% accuracy respectively, demonstrating that the methods work well for the prediction of signal peptides. Moreover, decision trees revealed that position P(1'), which is important in forming signal peptides, most commonly comprises either leucine or alanine. This concurs with the (P(3)-P(1)-P(1')) coupling model.</p>","PeriodicalId":87049,"journal":{"name":"Applied bioinformatics","volume":"5 1","pages":"13-9"},"PeriodicalIF":0.0,"publicationDate":"2006-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2165/00822942-200605010-00002","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"25906540","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}
Pingping Guan, Channa K Hattotuwagama, Irini A Doytchinova, Darren R Flower
{"title":"MHCPred 2.0: an updated quantitative T-cell epitope prediction server.","authors":"Pingping Guan, Channa K Hattotuwagama, Irini A Doytchinova, Darren R Flower","doi":"10.2165/00822942-200605010-00008","DOIUrl":"https://doi.org/10.2165/00822942-200605010-00008","url":null,"abstract":"<p><strong>Unlabelled: </strong>The accurate computational prediction of T-cell epitopes can greatly reduce the experimental overhead implicit in candidate epitope identification within genomic sequences. In this article we present MHCPred 2.0, an enhanced version of our online, quantitative T-cell epitope prediction server. The previous version of MHCPred included mostly alleles from the human leukocyte antigen A (HLA-A) locus. In MHCPred 2.0, mouse models are added and computational constraints removed. Currently the server includes 11 human HLA class I, three human HLA class II, and three mouse class I models. Additionally, a binding model for the human transporter associated with antigen processing (TAP) is incorporated into the new MHCPred. A tool for the design of heteroclitic peptides is also included within the server. To refine the veracity of binding affinities prediction, a confidence percentage is also now calculated for each peptide predicted.</p><p><strong>Availability: </strong>As previously, MHCPred 2.0 is freely available at the URL http://www.jenner.ac.uk/MHCPred/</p><p><strong>Contact: </strong>Darren R. Flower (darren.flower@jenner.ac.uk).</p>","PeriodicalId":87049,"journal":{"name":"Applied bioinformatics","volume":"5 1","pages":"55-61"},"PeriodicalIF":0.0,"publicationDate":"2006-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2165/00822942-200605010-00008","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"25908652","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":"OligoMatcher: analysis and selection of specific oligonucleotide sequences for gene silencing by antisense or siRNA.","authors":"SudhaRani Mamidipalli, Mathew Palakal, Shuyu Li","doi":"10.2165/00822942-200605020-00008","DOIUrl":"https://doi.org/10.2165/00822942-200605020-00008","url":null,"abstract":"<p><strong>Unlabelled: </strong>OligoMatcher is a web-based tool for analysis and selection of unique oligonucleotide sequences for gene silencing by antisense oligonucleotides (ASOs) or small interfering RNA (siRNA). A specific BLAST server was built for analysing sequences of ASOs that target pre-mRNA in the cell nucleus. Tissue- and cell-specific expression data of potential cross-reactive genes are integrated in the OligoMatcher program, which allows biologists to select unique oligonucleotide sequences for their target genes in specific experimental systems.</p><p><strong>Availability: </strong>The OligoMatcher web server is available at http://shelob.cs.iupui.edu:18081/oligomatch.php. The source code is freely available for non-profit use on request to the authors.</p><p><strong>Contact: </strong>Mathew Palakal (mpalakal@cs.iupui.edu) or Shuyu Li (li_shuyu_dan@lilly.com).</p>","PeriodicalId":87049,"journal":{"name":"Applied bioinformatics","volume":"5 2","pages":"121-4"},"PeriodicalIF":0.0,"publicationDate":"2006-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2165/00822942-200605020-00008","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"26041963","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}
Yuan Ji, Kevin Coombes, Jiexin Zhang, Sijin Wen, James Mitchell, Lajos Pusztai, W Fraser Symmans, Jing Wang
{"title":"RefSeq refinements of UniGene-based gene matching improve the correlation of expression measurements between two microarray platforms.","authors":"Yuan Ji, Kevin Coombes, Jiexin Zhang, Sijin Wen, James Mitchell, Lajos Pusztai, W Fraser Symmans, Jing Wang","doi":"10.2165/00822942-200605020-00003","DOIUrl":"https://doi.org/10.2165/00822942-200605020-00003","url":null,"abstract":"<p><p>Matching genes across microarray platforms is a critical step in meta-analysis. Standard practice uses UniGene to match genes. Numerous studies have found poor correlations between platforms when using UniGene matching. We profiled samples from 33 breast cancer patients on two different microarray platforms (Affymetrix and cDNA) and investigated gene matching. Our results confirmed that UniGene-based matching led to poor correlations of gene expression between platforms. Using RefSeq, a database maintained by the National Center for Biotechnology Information (NCBI), we developed and implemented a new method to refine gene matching. We found that the correlations between gene expression measurements were substantially higher after the RefSeq matching. Our approach differs from previously reported sequence-matching approaches and retains useful expression measurements. It is a sensible approach for matching probes across platforms. We conclude that UniGene alone is insufficient to match genes across platforms. Refined matching based on RefSeq significantly improves the quality of matches.</p>","PeriodicalId":87049,"journal":{"name":"Applied bioinformatics","volume":"5 2","pages":"89-98"},"PeriodicalIF":0.0,"publicationDate":"2006-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2165/00822942-200605020-00003","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"26041958","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}
Mugdha Gadgil, Sarika Mehra, Vivek Kapur, Wei-Shou Hu
{"title":"TimeView: for comparative gene expression analysis.","authors":"Mugdha Gadgil, Sarika Mehra, Vivek Kapur, Wei-Shou Hu","doi":"10.2165/00822942-200605010-00005","DOIUrl":"https://doi.org/10.2165/00822942-200605010-00005","url":null,"abstract":"<p><strong>Unlabelled: </strong>TimeView is a MATLAB program that compares multiple temporal datasets from microarray experiments under two or more conditions, for example, temporal variation of cellular response upon exposure to different drugs. The current paucity of programs designed to efficiently compare and visualise gene expression profiles in such datasets led us to design TimeView, which also enhances data visualisation by plotting the expression profiles of a large number of genes on a single screen.</p><p><strong>Availability: </strong>TimeView is available free of charge to all users at http://hugroup.cems.umn.edu/Research/Genomics/Timeview/timeview.htm. To use TimeView, users will require access to the commercial software MATLAB (version 6.5). A help document is available on the TimeView website.</p>","PeriodicalId":87049,"journal":{"name":"Applied bioinformatics","volume":"5 1","pages":"41-4"},"PeriodicalIF":0.0,"publicationDate":"2006-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2165/00822942-200605010-00005","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"25908649","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":"Simulation study of ratio calculation formulae of two-colour cDNA microarray data.","authors":"Hui Jia, Le Lu, Shiau-Chuen Hng, Jinming Li","doi":"10.2165/00822942-200605040-00008","DOIUrl":"https://doi.org/10.2165/00822942-200605040-00008","url":null,"abstract":"<p><p>In cDNA microarray image processing, there are different methods for calculating the channel ratios. Standard microarray image analysis software, such as the Axon GenePix Pro, calculate the channel ratio from pixels that define a given spot using different methods (i.e. ratio of means, ratio of medians, mean of ratios, median of ratios, and regression ratio). Ratio values calculated using the different methods will then be listed in an output file. Microarray users have to choose one of the available methods at their own discretion, as no guidelines are provided. Therefore, we aim to address one of the most frequently asked questions by the microarray users: which ratio quantity provided by the image analysis software should be used? In this study, we have evaluated the five different ratio calculation approaches using simulation studies. Our results suggest that in most circumstances the ratio of means appears to be the best approach, particularly when the coefficient of variance (CV) of two-channel pixel intensities are small (<0.5) and channel intensities are large. Conversely, the ratio of medians and the median of ratios are more favourable when the CV is large.</p>","PeriodicalId":87049,"journal":{"name":"Applied bioinformatics","volume":"5 4","pages":"255-66"},"PeriodicalIF":0.0,"publicationDate":"2006-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2165/00822942-200605040-00008","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"26473709","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":"AMarge: Automated Extensive Quality Assessment of Affymetrix chips.","authors":"Juan José Lozano, Susana G Kalko","doi":"10.2165/00822942-200605010-00006","DOIUrl":"https://doi.org/10.2165/00822942-200605010-00006","url":null,"abstract":"<p><strong>Unlabelled: </strong>AMarge is a web tool for the automatic quality assessment of Affymetrix GeneChip data. It is essential to have a trustworthy set of chips in order to derive gene expression data for phenotypic analysis, and AMarge provides a complete and rigorous web-accessible tool to fulfill this need. The quality assessment steps include image plots of weights derived from a robust linear model fit of the data, a 3'/5' RNA digestion plot, and Affymetrix Microarray Suite version 5.0 (MAS 5.0) quality standard procedures. Furthermore, robust multi-array average expression values are generated in order to have a start-up expression set for the subsequent analysis. The results of the complete analysis are summarised and returned as an HTML report.</p><p><strong>Availability: </strong>The AMarge web interface is accessible at http://nin.crg.es/cgi-binf/AMargeWeb.cgi. A mirror server is also available at http://bioinformatics.istge.it/AMarge-bin/AMargeWeb.cgi. The software implementing all these methods is part of the Bioconductor project (http://www.bioconductor.org).</p>","PeriodicalId":87049,"journal":{"name":"Applied bioinformatics","volume":"5 1","pages":"45-7"},"PeriodicalIF":0.0,"publicationDate":"2006-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2165/00822942-200605010-00006","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"25908650","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}
Casey Frankenberger, Xiaolin Wu, Jerry Harmon, Deanna Church, Lisa M Gangi, David J Munroe, Ulises Urzúa
{"title":"WebaCGH: an interactive online tool for the analysis and display of array comparative genomic hybridisation data.","authors":"Casey Frankenberger, Xiaolin Wu, Jerry Harmon, Deanna Church, Lisa M Gangi, David J Munroe, Ulises Urzúa","doi":"10.2165/00822942-200605020-00009","DOIUrl":"https://doi.org/10.2165/00822942-200605020-00009","url":null,"abstract":"<p><strong>Unlabelled: </strong>Gene copy number variations occur both in normal cells and in numerous pathologies including cancer and developmental diseases. Array comparative genomic hybridisation (aCGH) is an emerging technology that allows detection of chromosomal gains and losses in a high-resolution format. When aCGH is performed on cDNA and oligonucleotide microarrays, the impact of DNA copy number on gene transcription profiles may be directly compared. We have created an online software tool, WebaCGH, that functions to (i) upload aCGH and gene transcription results from multiple experiments; (ii) identify significant aberrant regions using a local Z-score threshold in user-selected chromosomal segments subjected to smoothing with moving averages; and (iii) display results in a graphical format with full genome and individual chromosome views. In the individual chromosome display, data can be zoomed in/out in both dimensions (i.e. ratio and physical location) and plotted features can have 'mouse over' linking to outside databases to identify loci of interest. Uploaded data can be stored indefinitely for subsequent retrieval and analysis. WebaCGH was created as a Java-based web application using the open-source database MySQL.</p><p><strong>Availability: </strong>WebaCGH is freely accessible at http://129.43.22.27/WebaCGH/welcome.htm</p><p><strong>Contact: </strong>Xiaolin Wu (forestwu@mail.nih.gov) or Ulises Urzúa (uurzua@med.uchile.cl).</p>","PeriodicalId":87049,"journal":{"name":"Applied bioinformatics","volume":"5 2","pages":"125-30"},"PeriodicalIF":0.0,"publicationDate":"2006-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2165/00822942-200605020-00009","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"26044074","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}
Yongqing Zhang, Antonio Ferreira, Cheng Cheng, Yongchun Wu, Jiong Zhang
{"title":"Modeling oligonucleotide microarray signals.","authors":"Yongqing Zhang, Antonio Ferreira, Cheng Cheng, Yongchun Wu, Jiong Zhang","doi":"10.2165/00822942-200605030-00003","DOIUrl":"https://doi.org/10.2165/00822942-200605030-00003","url":null,"abstract":"<p><p>Chemical principles dictate that the specific binding of a target to its complementary probes on a DNA microarray surface, and the nonspecific binding between other nucleotide segments and the same probes, are mutually competitive. We demonstrate that this mechanism can be understood by considering the competitive chemical reaction taking place on the microarray surface. Inspired by the pioneering work of Zhang and Hekstra, we have developed a physical model for microarray signal analysis, based on possible reaction mechanisms, and implemented it with a parallel, generic, simulated-annealing algorithm. Using data supplied by the Affymetrix Latin-square spike-in experiments, our model showed excellent fitting of the data. This correlation between the predicted expression levels and the spike-in concentrations of test transcripts demonstrated good predictive abilities of our model.</p>","PeriodicalId":87049,"journal":{"name":"Applied bioinformatics","volume":"5 3","pages":"151-60"},"PeriodicalIF":0.0,"publicationDate":"2006-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2165/00822942-200605030-00003","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"26269211","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}
Veera D'mello, Ju Y Lee, Clinton C MacDonald, Bin Tian
{"title":"Alternative mRNA polyadenylation can potentially affect detection of gene expression by affymetrix genechip arrays.","authors":"Veera D'mello, Ju Y Lee, Clinton C MacDonald, Bin Tian","doi":"10.2165/00822942-200605040-00007","DOIUrl":"https://doi.org/10.2165/00822942-200605040-00007","url":null,"abstract":"<p><p>DNA microarrays have been widely used to examine gene expression. The Affymetrix GeneChip is one of the most commonly used platforms, employing DNA probes of 25 nucleotides designed to hybridise to different regions of target mRNA. The targeted region is often biased toward the 3' end of mRNA, which can lead to biases in detection. A large number of mammalian genes can undergo alternative polyadenylation under different cellular conditions. Multiple polyadenylation sites can lead to variable transcripts with different hybridisation properties. Here, we surveyed probes on human, mouse and rat GeneChip arrays and found that the detection of a significant proportion of mRNAs can potentially be affected by alternative polyadenylation. This could lead to inaccurate interpretation of GeneChip data when the changes of expression values actually result from alternative use of polyadenylation sites.</p>","PeriodicalId":87049,"journal":{"name":"Applied bioinformatics","volume":"5 4","pages":"249-53"},"PeriodicalIF":0.0,"publicationDate":"2006-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2165/00822942-200605040-00007","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"26473708","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}