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3D-COFFEE Mixing Sequences and Structures Cédric Notredame
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chite ---ADKPKRPLSAYMLWLNSARESIKRENPDFK-VTEVAKKGGELWRGLKD wheat --DPNKPKRAPSAFFVFMGEFREEFKQKNPKNKSVAAVGKAAGERWKSLSE trybr KKDSNAPKRAMTSFMFFSSDFRS----KHSDLS-IVEMSKAAGAAWKELGP mouse -----KPKRPRSAYNIYVSESFQ----EAKDDS-AQGKLKLVNEAWKNLSP ***. :::.:... :.. *. *: * chite AATAKQNYIRALQEYERNGG- wheat ANKLKGEYNKAIAAYNKGESA trybr AEKDKERYKREM--------- mouse AKDDRIRYDNEMKSWEEQMAE * :.*. : Potential Uses of A Multiple Sequence Alignment? Extrapolation Motifs/Patterns Phylogeny Profiles Struc. Prediction Multiple Alignments Are CENTRAL to MOST Bioinformatics Techniques.
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Why Is It Difficult To Compute A multiple Sequence Alignment? A CROSSROAD PROBLEM BIOLOGY: What is A Good Alignment COMPUTATION What is THE Good Alignment chite ---ADKPKRPLSAYMLWLNSARESIKRENPDFK-VTEVAKKGGELWRGLKD wheat --DPNKPKRAPSAFFVFMGEFREEFKQKNPKNKSVAAVGKAAGERWKSLSE trybr KKDSNAPKRAMTSFMFFSSDFRS----KHSDLS-IVEMSKAAGAAWKELGP mouse -----KPKRPRSAYNIYVSESFQ----EAKDDS-AQGKLKLVNEAWKNLSP ***. :::.:... :.. *. *: *
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Why Is It Difficult To Compute A multiple Sequence Alignment ? BIOLOGY CIRCULAR PROBLEM.... Good Sequences Good Alignment COMPUTATION
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The T-Coffee Algorithm
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Local Alignment Global Alignment Extension Multiple Sequence Alignment Mixing Local and Global Alignments
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What is a library? Extension+T-Coffee Library Based Multiple Sequence Alignment 2 Seq1 MySeq Seq2 MyotherSeq #1 2 1 1 25 3 8 70 …. 3 Seq1 anotherseq Seq2 atsecondone Seq3 athirdone #1 2 1 1 25 #1 3 3 8 70 ….
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The Triplet Assumption X Y Z X Y SEQ A SEQ B Consistency Consensus
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ClustalWT-Coffee
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Dynamic Programming Using An Extended Library Progressive Alignment
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What Is BaliBase How Good is T-Coffee ??? Best Performing Method on MSA benchmark Datasets BaliBase -Notredame -Sonhammer Ribosomal RNA -Katoh (Mafft) Homstrad -Notredame OxBench -Barton
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Mixing Heterogenous Data With T-Coffee Local AlignmentGlobal Alignment Multiple Sequence Alignment Multiple Alignment StructuralSpecialist
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Mixing Sequences and Structures
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Why Do We Want To Mix Sequences and Structures? 1-Predicting Sequence Structures STUCTURE FUNCTION
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Why Do We Want To Mix Sequences and Structures? Sequences are Cheap and Common. Structures are Expensive and Rare.
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Why Do We Want To Mix Sequences and Structures? Cheapest Structure determination: Sequence-Structure Alignment THREAD Or ALIGN ADKPRRP---LS-YMLWLN ADKPKRPKPRLSAYMLWLN
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Why Do We Want To Mix Sequences and Structures? ADKPRRP---LS-YMLWLN ADKPKRPKPRLSAYMLWLN THREAD Or ALIGN Convincing Alignment Same Fold
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Why Do We Want To Mix Sequences and Structures? Convincing Alignment Same Fold Distant sequences are hard to align
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Why Do We Want To Mix Sequences and Structures? chite ---ADKPKRPLSAYMLWLNSARESIKRENPDFK-VTEVAKKGGELWRGLKD wheat --DPNKPKRAPSAFFVFMGEFREEFKQKNPKNKSVAAVGKAAGERWKSLSE trybr KKDSNAPKRAMTSFMFFSSDFRS----KHSDLS-IVEMSKAAGAAWKELGP mouse -----KPKRPRSAYNIYVSESFQ----EAKDDS-AQGKLKLVNEAWKNLSP ***. :::.:... :.. *. *: * Multiple Sequence Alignments Help Exploring the Twilight Zone
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Why Do We Want To Mix Sequences and Structures? 1-Predicting Sequence Structures 2-Produce Better Alignments
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Why Do We Want To Mix Sequences and Structures? ADKPRRP---LS-YMLWLN ADKPKRPKPRLSAYMLWLN ALIGN Unreliable alignment if %ID <30%
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Why Do We Want To Mix Sequences and Structures? Alignment Unsentitive to %ID ADKPRRP---LS-YMLWLN ADKPKRPKPRLSAYMLWLN Struc. Superposition Folds evolve Slower than Sequences
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Why Do We Want To Mix Sequences and Structures?
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Structure Superposition
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Why Do We Want To Mix Sequences and Structures? 1-Predicting Sequence Structures 2-Produce Better Alignments
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How To Mix Sequences and Structures
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Mixing Heterogenous Data With T-Coffee Local AlignmentGlobal Alignment Multiple Sequence Alignment Multiple Alignment StructuralSpecialist
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Struct Vs Struct Seq Vs Struct Thread Evaluation on Homestrad Superpose Seq Vs Seq Local Global Mixing Sequences and Structures with T-Coffee
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The 3D-Coffee Libraries Methods Global: Needlman and Wunsch Local:Sim (lalign) Threading: Fugue Superposition:SAP
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Threading: Fugue
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Fugue Threading: Fugue
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Fugue Threading: Fugue 1-Turn Sequence into a profile: -lower penalties in loops -Structure specific matrix 2- Align Profile with Sequence
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Evaluating Fugue Threading: Fugue 1-Select 967 pairs of sequences in HOMSTRAD FUGUE T-Coffee 2-Align each pair with T-Coffee and Fugue. Compare 3-Compare the Two Alignments
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Fugue Threading: Fugue 1-Select 967 pairs of sequences in HOMSTRAD 2-Align each pair with T-Coffee and Fugue. 3-Compare the Two Alignments TCdef wins Fugue wins TCdef:58.81% Fugue:61.81%
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Superposition: SAP
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Superposition:SAP
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1-High Level Dynamic Programming Substitution Matrix when doing regular Alignments 2-Low Level DP. Forcing the aln of two residues
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1-High Level Dynamic Programming Superposition:SAP 1 9 12 13 1 8 14 5 3-Rigid Body Superposition RMSD 2-Low Level DP. Forcing the aln of two residues
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1-High Level Dynamic Programming Superposition:SAP 1 9 12 13 1 8 14 5 3-Rigid Body Superposition RMSD 2-Low Level DP. Forcing the aln of two residues
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1-High Level Dynamic Programming Superposition:SAP 3-Rigid Body Superposition 2-Low Level DP. Evaluate Every Pair
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1-High Level Dynamic Programming Superposition:SAP Structure Based Sequence Alignment Make a DP on the accumulated traces Use Traces like a Substitution Matrix
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1-Select 967 pairs of sequences in HOMSTRAD 2-Align each pair with T-Coffee and SAP. 3-Compare the Two Alignments Superposition:SAP
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1-Select 967 pairs of sequences in HOMSTRAD 2-Align each pair with T-Coffee and SAP. 3-Compare the Two Alignments Superposition:SAP TCdef:58.81% SAP:86.31%
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SAPFugue TCdef:58.81% Fugue:61.81% TCdef:58.81% Fugue:86.31%
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Sequences and Structures: How Good is The Mixture ???
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Our Benchmark: HOM39 -HOMSTRAD: Structure based MSAs that can be used as References. -COMPACT and DEMANDING -HOM39: The 39 Most difficult datasets (percent ID lower than 25).
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Our BenchMark: Using HOM39 BENCHMARKING Strategy: -re-align HOM39 without using ALL the structures -Compare the result with the reference
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Evaluating 3D-Coffee 1- Can a SINGLE structure Help ?
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Seq Vs Struct Thread Evaluation on HOM39 Seq Vs Seq Local Global Using ONE structure with 3D-Coffee HOM39 with ONE Structure per MSA
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Evaluating 3D-Coffee 1- Can a SINGLE structure Help ? 2- Does it benefit to ALL the Sequences Is EVERYONE Happier if there is a STAR in the team…
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BaliBase HOM39 TC-Fugue + Remove Provided Structure(s) Comparison
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Evaluating 3D-Coffee 1- Can a SINGLE structure Help ? 3- Can We Use Two or More Structures 2-Does it benefit to all the sequences
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Seq Vs Struct Fugue Evaluation on Homestrad Seq Vs Seq Local Global Mixing Sequences and Structures with 3D-Coffee HOM39 with TWO Structures/MSA Struct Vs Struct SAP, LSQ
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Indirect Improvement Direct Improvement
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Evaluating 3D-Coffee 1- Can a SINGLE structure Help ? 4-Relation Accuracy/ N-structures ??? 2-Does it benefit to all the sequences 3-Can we use Two Structures
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Seq Vs Struct Fugue Evaluation on Homestrad Seq Vs Seq Local Global Mixing Sequences and Structures with T-Coffee HOM39 with 1-N Structures per MSA Struct Vs Struct SAP
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Induced Improvement
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Conclusion
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-Structures Help BUT NOT SO MUCH
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The More Structures The Merrier
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Credits Orla O’Sullivan: University College, Cork, Ireland Des Higgins: University College, Cork, Ireland Karsten Suhre: IGS-CNRS, Marseille, France
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Conclusion The program is available on request from: cedric.notredame@europe.com
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