MS Thesis Summary: Protein Structure Database for

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Transcript MS Thesis Summary: Protein Structure Database for

M.S. Thesis Defense

Protein Structure Database for Structural Genomics Group

Jessica Lau December 13, 2004

• • • • • • • • Bioinformatics is Analysis of biological data: gene expression, DNA sequence, protein sequence. Data mining and management of biological information through database systems.

• • • At the Northeast Structural Genomics Consortium, database management systems play a large role in its daily operation Data collection and mining of experimental results Track target progress – status milestones Exchange information with rest of the world My thesis presents work in database management systems at the NESG.

Part 1: ZebaView Part 2: Worm Structure Gallery Part 3: Prototype of NESG Structure Gallery

• Zebaview is the official target list of the Northeast Structural Genomics Consortium • Display summary table of NESG targets.

– Status milestones – Protein properties: DNA and protein sequences, molecular weight, isoelectric point • New targets are curated and then uploaded to SPiNE. • 11,284 targets from 88 organisms.

Family View

NESG Families • Unfolded • Membrane • Core 50 • Nf-kB

Target Summary Statistics

Selected  Cloned  Expressed X-ray or NMR data collection   Soluble  In PDB Purified  90 35 80 30 70 25 60 50 20 Prokaryotic Eukaryotic Prokaryotic Eukaryotic • 4,418 targets cloned • 141 structures • 3.4% successful targets 40 15 30 10 20 5 10 0 0

GO, Cellular Localization, and SignalP

Search for targets that have

any of the three GO ontologies defined

no GO ontologies defined at all

116 NESG structures do not have Molecular Function defined

LOCTarget

Bovine ribonuclease A has four disulfide bonds to stabalize its 3-D structure.

Mahesh Narayan, et al. (2000) Acc. Chem. Res., 33 (11), 805 -812. • Secretory proteins require formation of disulfide bonds • Oxidative Folding needed for proper native folding • 2,132 “Extracellular” NESG targets

SignalP

Lodish et al. Molecular Cell Biology 4 th 7.1 (2000) edition, Figure • mRNA are translated with signal peptide for cellular localization • Peptide is cleaved upon destination • SignalP predicts cleavage of signal peptide • Removal of signal peptide gives proper native fold

Part 2 – Worm Structure Gallery

Caenorhabditis elegans

– Widely studied model organism • 2-3 weeks life span, small size (1.5-mm-long), ease of laboratory cultivation, transparent body • Small genome, yet has complex organ systems similar to higher organisms: digestive, excretory, neuromuscular, reproductive systems Donald Riddle et al, C. elegans II (1997) Altun Z F and Hall DH. , Atlas of C. elegans Anatomy, Wormatlas (2002-2004)

System Components

• 22,653 C. elegans proteins • 42 experimentally determined • 4 are from NESG • 24 homology models • 14 are from NESG • 960 C. elegans proteins potentially modeled • Uniprot: Pfam domain, Gene name, ORF name • PDB Coordinates • Structure Validation Report • Sequence similarities to proteins in PDB

Protein Structure Validation Software

• Suite of quality validation software – PROCHECK • Quality of experimental data • Distribution of φ, ψ angles in Ramachandran plot – MolProbity Clashscore • Number of H atom clashes per 1,000 atoms • With respect to a set of scores from 129 high resolution X-ray crystal structures • < 500 residues, of resolution <= 1.80 Å, R-factor <= 0.25 and R-free <= 0.28; Bahattacharya, A et al. to be published

Homology Modeling Automatically (HOMA)

• Algorithm based on alignment between query and template sequences.

– Regions of conserved residues forms a set of constraints for modeling • Sequence identity of 40% or more • Good quality template

Bad alignment  Bad model

Poor quality template  Poor quality model

Quality scores of 3-D structures

-10

Quality Z-scores - Homology Models vs. Experimentally Determined Structures

-8 -6 -4 -2 -10 -15 -20 -25 -30 -35 -40 -45 5 0 -5 0 Homology Models Experimentally Determined Structures

Procheck (all) z-score

2

Search

• Search for C. elegans proteins in local database.

• Keyword: “Ubiquitin” in any field Results: 72 C. elegans proteins 2 Experimentally determined structures 1 Homology model 11 Potential models

System Architecture

• Java, Tomcat, MySQL, Perl.

Three-tier architecture • Client: Web browser • Application: JSP, Logic components, Data access components • Data: MySQL

Part 3 – NESG Structure Gallery

• Structure files submitted by automated pipeline • ADIT integrated with SPiNE for uniform format • PSVS and images automatically generated • Structure information from PSVS directly into SPiNE • Archives structure files.

• Structure files submitted by individual groups • Structure information is entered into SPiNE manually • Manually run PSVS and MolScript

• Downloads – Structure Validation Report – Structure related files • Atomic coordinates • NMR constraints • NMR peak lists • Chemical shifts • Structure factor • Annotation – Functional annotation provided by other NESG members – Uniprot – PDB coordinates file • Reusing Java components from Worm Structure Gallery

– Enhance ZebaView performance to handle increased load and functionalities – Integrate annotation from other protein and structure databases. – Make modules available for other java-based applications within structural genomics.

– Develop a gallery for other organisms: yeast, fruit fly, human – Continue specifications for the new NESG Structure Gallery

Advisor: Dr. Gaetano Montelione Thanks to everyone at the Protein NMR lab and NESG!

Aneerban Bhattacharya John Everett All the scientists who solved the structures!