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Signaling, Microarrays, and Annotations. Michael Ochs Information Science and Technology, Fox Chase Cancer Center School of Biomedical Engineering, Drexel University. Microarrays and Biology. Models by Physics Bayesian Decomposition - An Approach to Solve the Problem
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Signaling, Microarrays, and Annotations Michael Ochs Information Science and Technology, Fox Chase Cancer Center School of Biomedical Engineering, Drexel University Fox Chase Cancer Center
Microarrays and Biology • Models by Physics • Bayesian Decomposition - An Approach to Solve the Problem • Results from Deletion Mutant Data Fox Chase Cancer Center
What a Model Means to Me Fox Chase Cancer Center
Stimulus Signal Transduction Transcription mRNA Signalling Pathways Downward, Nature, 411, 759, 2001 Fox Chase Cancer Center
MakingProteins Fox Chase Cancer Center
Post-Trans- lational Modification RNA Splicing miRNA A Closer Look at Translation Fox Chase Cancer Center
Block Protein-Protein Interaction Leads to Loss of Some Transcripts, Reduction of Others Depending on Active Signaling Pathways Model But the Gene Lists are Incomplete as are the Network Diagrams! Fox Chase Cancer Center
A B C D 3 1 2 A B C D Identifying Pathways 1 2 3 www.promega.com Fox Chase Cancer Center
Take measurements of thousands of genes, some of which are responding to stimuli of interest 3 1 2 And find the correct set of basis vectors that link to pathways * * * * * * then identify the pathways Goal of Analysis Fox Chase Cancer Center
Microarrays and Biology • Models by Physics • Bayesian Decomposition - An Approach to Perform Analysis • Results from Deletion Mutant Data Fox Chase Cancer Center
condition M condition 1 pattern 1 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * The behavior of one gene can be explained as a mixture of patterns with different behaviors pattern k BD: Matrix Decomposition condition 1 Distribution of Patterns condition M gene 1 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * pattern k pattern 1 gene 1 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * ** ** * * * * * * * * * * * * X = Patterns of Behavior gene N Data gene N Fox Chase Cancer Center
The Model • Pathways Linked to Multiply Regulated Genes • Positivity (No Negative Expression) • Classification • Group 1 is Tumor • Group 2 is Normal • Regulation • Genes Regulated by a Single Transcription Factor • Genes Known to be Coregulated (e.g., ribosomal proteins) Fox Chase Cancer Center
Correlations and Biology Distribution of Patterns Patterns of Behavior pattern k pattern 1 gene 1 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * ** ** * * * * * * * * * * * * pattern 1 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * pattern k condition M condition 1 gene N Fox Chase Cancer Center
Microarrays and Biology • Models by Physics • Bayesian Decomposition - An Approach to Perform Analysis • Results from Deletion Mutant Data Fox Chase Cancer Center
Deletion Mutant Data Set (Hughes et al, Cell, 102, 109, 2000) • 300 Deletion Mutants in S. cerevisiae • Biological/Technical Replicates with Gene Specific Error Model • Filter Genes • >25% Data Missing in Ratios or Uncertainties • < 2 Experiments with 3 Fold Change • Filter Experiments • < 2 Genes Changing by 3 Fold 228 Experiments/764 Genes Fox Chase Cancer Center
Mutant M Mutant 1 pattern 1 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * pattern k BD: Matrix Decomposition Distribution of Patterns (what genes are in patterns) Mutant 1 Mutant M gene 1 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * pattern k pattern 1 gene 1 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * ** * * * * * * * * * * * * * * X = Patterns of Behavior (does mutant contain pattern) gene N Data gene N Fox Chase Cancer Center
Pattern 1 403 Genes Pattern 2 410 Genes Pattern 3 390 Genes Genes in Patterns • Pattern 4 • 276 Genes • Pattern 5 • 355 Genes • Pattern 6 • 297 Genes • Pattern 7 • 223 Genes Fox Chase Cancer Center
Annotating Genes • Goals Being Left Behind • Identifying a List of Differentially Expressed Genes • Discriminating Classes • Goals Now of Interest • Identifying Changes in Pathways • Identifying Active Biological Processes • Identifying Active Biological Functions Fox Chase Cancer Center
Location Function Process Gene Ontology Fox Chase Cancer Center
Those are all PROTEINS! • ESTs and Oligonucleotides • Short Sequences, Not Proteins, Not Genes • Need to Link these to Genes • Clustering Sequences • UNIGENE/LocusLink • TIGR Gene Indices • BLAST • Annotating Genes • Experimental • Computational Fox Chase Cancer Center
UNIGENE • Take ESTs, Align Together • EST ~400 nucleotides • Mismatch Allowed Reasonably High • 123,995 “Genes” • ~10,000 Experimental Genes • ~few thousand Estimated Genes Fox Chase Cancer Center
TIGR • Take ESTs, Align Together into TC • EST ~400 nucleotides • Highly Restrictive Match • 40 bp, 90% match, • max 30 bp gap Fox Chase Cancer Center
Annotating Genes Fox Chase Cancer Center
Gene Ontology (Process) Fox Chase Cancer Center
Amount of Behavior Explained by Mating Pathway for Mutants Mating Response P Ste2 Ste20 Ste5 Ste11 Ste7 Fus3 Ste12 (Posas, et al, Curr Opin Microbiology, 1, 175, 1998) Fox Chase Cancer Center
Conclusions • BD Identifies Patterns Related to Underlying Physiology • BD Uses Prior Knowledge to Guide Data Analysis • With Adequate Information, BD Links Expression Changes to Pathway Activity • Proteomics, TF Binding Data, and Future Data Types are Easily Included Fox Chase Cancer Center
Tom Moloshok Jeffrey Grant Yue Zhang Elizabeth Goralczyk Luke Somers Michael Slifker Collaborators Godwin (FCCC) B. Eisenberg (FCCC > Dartmouth) J.-M. Claverie (CNRS) G. Parmigiani (JHU) E. Korotkov (RAS) Acknowledgements Fox Chase Ghislain Bidaut Andrew Kossenkov Vladimir Minayev Garo Toby Bill Speier (Johns Hopkins) Daniel Chung DJ Datta (UCSF) Frank Manion Bob Beck Fox Chase Cancer Center