UCSC BME 205 Fall 2005

Bioinformatics: Models and Algorithms

Schedule

(Last Update: 08:07 PST 13 March 2006 )

Reading assignments

Reading assignments in Biological Sequence Analysis: Probabilistic Models of Proteins and Nucleic Acids by R. Durbin, S. Eddy, A. Krogh, and G. Mitchison.

Date Have read these sections
3 Oct 2005 1.1–1.4
10 Oct 2005 11.1–11.6
17 Oct 2005 2.1–2.9
24 Oct 2005 3.1–3.6
31 Oct 2005 5.1–5.8
7 Nov 2005 6.1–6.5
14 Nov 2005 7.1–7.6

Lecture and Homework Schedule

The lecture schedule reflects the material actually delivered. To get an idea what is coming up, see last year's schedule.

Date Lecture Topic(s) Due
Fri 23 Sept administrivia, fundamental dogma, DNA
Mon 26 Sept models: DNA AT pair, protein backbone, alpha helices, sidechains GAILV
Wed 28 Sept models: beta sheets parallel/antiparallel, type I/II hairpin turns, residues ST
Fri 30 Sept multiple alignments, A2M format, models: CHDEFYW, disulfides, coordinating metal ions, aromatics
Mon 3 Oct Phoenix Eagleshadow (fellowships); codons, stochastic models as computable probability functions, Bayes rule
Wed 5 Oct zero-order and first-order Markov chains; stop characters; factoring out length model; mention of higher order chains
Fri 7 Oct log-probability for computation, efficient addition of probs in log-prob space, train/crosstrain/test, n-fold cross-validation perl 1 (noon)
Mon 10 Oct setting parameters for zero-order Markov model, derivation of maximum-likelihood estimate (MLE) using Lagrange multipliers, pseudocounts as mean a posteriori (MAP) estimate without derivation, use of zero-order model as pseudocounts for first-oder model, notion of P-value (for single trial) and E-value
Wed 12 Oct review of returned homework; questions on Darling models (cis and trans conformations, CDA and DAC angles); P1, Pn, and E-value; equivalence of E and Pn for small E
Fri 14 Oct Z-scores; Gaussian vs. Extreme-value (Gumbel) distribution; pdf and cdf for extreme value; derivation of linear tail; Shannon entropy; information gain Darling models (noon)
Mon 17 Oct information gain, entropy and relative entropy, Kullbak-Leibler divergence, (contrasted relative entropy and difference in entropy), sequence logos
Wed 19 Oct sequence logos, mutual information, ROC plots
Fri 21 Oct ROC plots, sensitivity, selectivity, precitions, ROCn plots, started discussion on sequence alignment Fellowship application (noon)
Mon 24 Oct Subsitution matrices; scoring gapless alignments; diferent gap cost models
Wed 26 Oct global alignment arbitrary gap costs and traceback; global alignment with linear gap costs
Fri 28 Oct feedback on fellowship applications; global alignment with linear and affine gap costs; traceback on linear gap costs perl 2 (noon)
Mon 31 Oct global and local alignment for affince gap costs, with traceback
Wed 2 Nov Intro to hidden Markov models
Fri 4 Nov Catherine Soehner and Christy Hightower (Science Library) perl 3 (noon)
Mon 7 Nov David Kulp (U. Mass. Amherst) Causal inference of regulator-target pairs by gene mapping of expression phenotypes
The combination of whole genome expression profiling and polymorphic marker screening has emerged as an ideal genetic perturbation model to detect causal relationships among genes. By treating expression as a quantitative phenotype, linkage analysis can reveal associated regulatory loci. We developed an epistatic-like linkage model to jointly account for gene expression and genotype and precisely map regulator genes. A consideration of complete and reduced forms of the model provides the means to dissect regulator-target relationships as causal or merely dependent. In simulations we find that the model is robust with respect to multiple independent regulators and we show that, in yeast, regulator genes are accurately predicted and that regulatory modules derived from pairwise linkage have biological significance.
Wed 9 Nov review of HMM forward algorithm; HMM backward algorithm to get P(state s in position i|sequence)
Fri 11 Nov NO CLASS (Veteran's Day)
Mon 14 Nov Quick review of forward-backward. Baum-Welch training. Profile HMMs (both HMMer's Plan 7 and SAM 9-edges) perl 4 (noon)
Wed 16 Nov Intro to Dirichlet mixtures
Fri 18 Nov More on Dirichlet mixtures perl 5 (noon)
Mon 21 Nov Multiple alignment. The problem, the progressive alignment heuristic. Problems with current benchmarks (favoring overalignment)
Wed 23 Nov Guest Lecture: Melissa Cline
Visualizing the effects of splice variation on protein interaction networks
High-throughput technologies have generated large networks of protein-protein interactions. These networks are a powerful aid to expression analysis, as they relate the expression values of individual genes in a framework that describes functional association, and perhaps causation. Cytoscape is an open-source package for visualization and modeling of protein interaction networks, with support for visualizing expression results from one or more experiments. Yet splice variation complicates this picture by removing interaction domains, and thus altering the network topology. Most network analysis packages do not take this into account. This talk describes work underway at the Pasteur and Max-Planck Institutes for translating protein interaction networks into protein domain interaction networks, and integrating these networks with exon expression results from the Affymetrix Human Exon array.
Fri 25 Nov NO CLASS
Mon 28 Nov Evolutionary trees. Paralogs vs. orthologs. %ID, % similar, converting identity to distance. Additivity assumption. UPGMA algorithm web and literature search (noon)
Wed 30 Nov Evolutionary trees. Ultrametric distances, UPGMA, and neighbor-joining. Brief mentions of maximum likelihood and parsimony.
Fri 2 Dec Stochastic context-free grammars and RNA structure perl 6 noon
Wed 7 Dec 4--7 p.m. exam period (NOT USED)


slug icon to go to Scool of Engineering home page
SoE home
sketch of Kevin Karplus by Abe
Kevin Karplus's home page
BME-slug-icon
BS, MS, and PhD programs
BME 205 home page Karplus's lab page UCSC Bioinformatics research

Questions about page content should be directed to

Kevin Karplus
Biomolecular Engineering
University of California, Santa Cruz
Santa Cruz, CA 95064
USA
karplus@soe.ucsc.edu
1-831-459-4250