Lecture 1

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Introduction to Bioinformatics

ChBi406/506

Ozlem Keskin

For today’s lectures Many slides from gersteinlab.org/courses/452

And

Bioinformatics and Functional Genomics by Jonathan Pevsner (ISBN 0-471-21004-8).

EMails

Ozlem Keskin

Engin Cukuroglu okeskin@ku.edu.tr

ecukuroglu@ku.edu.tr

Who is taking this course?

• People with very diverse backgrounds in biology, chemical engineering (MS/BS)

• People with diverse backgrounds in computer science please visit Attila Hoca’s office!

• Most people have a favorite gene, protein, or disease

What are the goals of the course?

• To provide an introduction to bioinformatics with a focus on the National Center for Biotechnology

Information (NCBI) and EBI

• To focus on the analysis of DNA, RNA and proteins

• To introduce you to the analysis of genomes

• To combine theory and practice to help you solve research problems

Themes throughout the course

Textbooks

Web sites

Literature references

Gene/protein families

Computer labs

Textbook

The course textbook is J. Pevsner, Bioinformatics and

Functional Genomics (Wiley, 2009).

Several other bioinformatics texts are available:

Baxevanis and Ouellette

Mount

Durbin et al.

Lesk

In our library you will find (e-book)

Bioinformatics [electronic resource] : sequence and genome analysis / David W.

Mount.

ImprintCold Spring Harbor, N.Y. : Cold Spring Harbor Laboratory Press, c2001.

Bioinformatics : a practical guide to the analysis of genes and proteins / editedby

Andreas D. Baxevanis, B.F. Francis Ouellette.

ImprintHoboken, N.J. : John Wiley, 2005.

(SOON)

Themes throughout the course:

Literature references

You are encouraged to read original source articles. Although articles are not required, they will enhance your understanding of the material.

You can obtain articles through PubMed and Web of Science.

Web sites

The course website is reached via: http://pevsnerlab.kennedykrieger.org/bioinfo_course.htm

(or Google “pevsnerlab”  courses)

This site contains the powerpoints for each lecture.

The textbook website is: http://www.bioinfbook.org

This has 1000 URLs, organized by chapter

This site also contains the same powerpoints.

You will also find the lecture slides at F-folder.

Grading

Midterm

Final

HWs

Project

30%

35%

20%

15%

(might change, the course will evolve)

Themes throughout the course: gene/protein families

We will use beta globin and retinol-binding protein 4

(RBP4) as model genes/proteins throughout the course.

Globins including hemoglobin and myoglobin carry oxygen. RBP4 is a member of the lipocalin family. It is a small, abundant carrier protein. We will study globins and lipocalins in a variety of contexts including

• --sequence alignment

• --gene expression

• --protein structure

• --phylogeny

• --homologs in various species

The HIV-1 pol gene encodes three proteins

Aspartyl protease

PR

Reverse transcriptase

RT

Integrase

IN

Outline for today (chapters 1 and 2)

Definition of bioinformatics

Overview of the NCBI website

Accessing information about DNA and proteins

--Definition of an accession number

--Four ways to find information on proteins and DNA

Access to biomedical literature

Bioinformatics

Biological

Data

+

Computer

Calculations

What is bioinformatics?

• Interface of biology and computers

• Analysis of proteins, genes and genomes using computer algorithms and computer databases

• Genomics is the analysis of genomes.

The tools of bioinformatics are used to make sense of the billions of base pairs of DNA that are sequenced by genomics projects.

Protein coordinates, DNA array data, annotated gene sequences

Biological information is being generated now days in parallel.

We can easily run 10,000 simultaneous experiments on a single DNA microarray.

To cope with this much data we really need computers.

So Bioinformatics is that field that combines biology and computers.

Where does Bioinformatics come from?

Data from the Human Genome Project has fueled the development of new bioinformatics methods

HGP

What is Bioinformatics?

• (Molecular) Bio informatics

• One idea for a definition?

Bioinformatics is conceptualizing biology in terms of molecules (in the sense of physical-chemistry) and then applying “informatics” techniques ( derived from disciplines such as applied math, CS, and statistics) to understand and organize the information associated with these molecules, on a large-scale.

• Interface of biology and computers

Analysis of proteins, genes and genomes using computer algorithms and computer databases

Genomics is the analysis of genomes.

The tools of bioinformatics are used to make sense of the billions of base pairs of DNA

• that are sequenced by genomics projects.

Top ten challenges for bioinformatics

[1] Precise models of where and when transcription will occur in a genome (initiation and termination)

[2] Precise, predictive models of alternative RNA splicing

[3] Precise models of signal transduction pathways; ability to predict cellular responses to external stimuli

[4] Determining protein:DNA, protein:RNA, protein:protein recognition codes

[5] Accurate ab initio protein structure prediction

Top ten challenges for bioinformatics

[6] Rational design of small molecule inhibitors of proteins

[7] Mechanistic understanding of protein evolution

[8] Mechanistic understanding of speciation

[9] Development of effective gene ontologies: systematic ways to describe gene and protein function

[10] Education: development of bioinformatics curricula

Source: Ewan Birney,

Chris Burge, Jim Fickett

Simulating the cell

On bioinformatics

“Science is about building causal relations between natural phenomena (for instance, between a mutation in a gene and a disease). The development of instruments to increase our capacity to observe natural phenomena has, therefore, played a crucial role in the development of science - the microscope being the paradigmatic example in biology. With the human genome, the natural world takes an unprecedented turn: it is better described as a sequence of symbols. Besides high-throughput machines such as sequencers and DNA chip readers, the computer and the associated software becomes the instrument to observe it, and the discipline of bioinformatics flourishes.

On bioinformatics

However, as the separation between us (the observers) and the phenomena observed increases (from organism to cell to genome, for instance), instruments may capture phenomena only indirectly, through the footprints they leave.

Instruments therefore need to be calibrated: the distance between the reality and the observation (through the instrument) needs to be accounted for. This issue of

Genome Biology is about calibrating instruments to observe gene sequences; more specifically, computer programs to identify human genes in the sequence of the human genome.”

Martin Reese and Roderic Guig ó, Genome Biology 2006 7(Suppl I):S1, introducing EGASP, the Encyclopedia of DNA Elements (ENCODE)

Genome Annotation Assessment Project

bioinformatics public health informatics medical informatics

Tool-users databases infrastructure algorithms

Tool-makers

Three perspectives on bioinformatics

The cell

The organism

The tree of life

Page 4

After Pace NR (1997)

Science 276:734

Page 6

Time of development

Body region, physiology, pharmacology, pathology

Page 5

DNA RNA protein phenotype

Page 5

DNA RNA protein phenotype

Growth of GenBank

Updated 8-12-04:

>40b base pairs

1982 1986 1990 1994 1998 2002

Year

Fig. 2.1

Page 17

Growth of GenBank

70

60

50

40

30

20

10

0

1985 1990 1995 2000

December

1982

June

2006

Growth of the International Nucleotide

Sequence Database Collaboration

Base pairs contributed by GenBank EMBL DDBJ http://www.ncbi.nlm.nih.gov/Genbank/

Central dogma of molecular biology

DNA RNA protein genome transcriptome proteome

Central dogma of bioinformatics and genomics

What is the Information?

Molecular Biology as an Information Science

• Central Dogma of Molecular Biology

DNA

-> RNA

-> Protein

-> Phenotype

-> DNA

• Molecules

– Sequence, Structure, Function

• Processes

– Mechanism, Specificity, Regulation

• Central Paradigm for Bioinformatics

Genomic Sequence

Information

-> mRNA (level)

-> Protein Sequence

-> Protein Structure

-> Protein Function

-> Phenotype

• Large Amounts of Information

– Standardized

– Statistical

•Genetic material

•Information transfer (mRNA)

•Protein synthesis (tRNA/mRNA)

•Some catalytic activity

•Most cellular functions are performed or facilitated by proteins.

•Primary biocatalyst

•Cofactor transport/storage

•Mechanical motion/support

•Immune protection

•Control of growth/differentiation

(idea from D Brutlag, Stanford, graphics from S Strobel)

• Proteins fold into 3D structures with specific functions which are reflected in a pheonotype.

• These functions are selected in a Darwinian sense by the environment of the phenotype.

• Which drives the evolution of the DNA sequence.

• Many Bioinformatics techniques address this flow of molecular biology information inside the organism hoping to understand the organization and control of genes even predicting protein structure from sequence.

• There is a second flow of information that bioinformatics seeks to address is the large amount of data generated by new high through methods.

Bioinformatics owes its lively hood to the availability of large data sets that are too complex to allow manual analysis.

DNA RNA protein phenotype genomic

DNA databases cDNA

ESTs

UniGene protein sequence databases

Fig. 2.2

Page 20

There are three major public DNA databases

EMBL GenBank DDBJ

The underlying raw DNA sequences are identical

Page 16

There are three major public DNA databases

EMBL

Housed at EBI

European

Bioinformatics

Institute

GenBank

Housed at NCBI

National

Center for

Biotechnology

Information

DDBJ

Housed in Japan

Page 16

>100,000 species are represented in GenBank all species viruses bacteria archaea eukaryota

128,941

6,137

31,262

2,100

87,147

Table 2-1

Page 17

The most sequenced organisms in GenBank

Homo sapiens (6.9 million entries)

Mus musculus (5.0 million)

Zea mays (896,000)

Rattus norvegicus (819,000)

Gallus gallus (567,000)

Arabidopsis thaliana (519,000)

Danio rerio (492,000)

Drosophila melanogaster (350,000)

Oryza sativa (221,000)

National Center for Biotechnology

Information (NCBI) www.ncbi.nlm.nih.gov

Taxonomy nodes at NCBI

8/06 http://www.ncbi.nlm.nih.gov/Taxonomy/txstat.cgi

The most sequenced organisms in GenBank

Homo sapiens

Mus musculus

Rattus norvegicus

Danio rerio

Zea mays

Oryza sativa

Drosophila melanogaster

Gallus gallus

Arabidopsis thaliana

10.7 billion bases

6.5b

5.6b

1.7b

1.4b

0.8b

0.7b

0.5b

0.5b

Updated 8-12-04

GenBank release 142.0

Table 2-2

Page 18

The most sequenced organisms in GenBank

Homo sapiens

Mus musculus

Rattus norvegicus

Danio rerio

Bos taurus

Zea mays

Oryza sativa (japonica)

Xenopus tropicalis

Canis familiaris

Drosophila melanogaster

Updated 8-29-05

GenBank release 149.0

11.2 billion bases

7.5b

5.7b

2.1b

1.9b

1.4b

1.2b

0.9b

0.8b

0.7b

Table 2-2

Page 18

The most sequenced organisms in GenBank

Homo sapiens

Mus musculus

Rattus norvegicus

Bos taurus

12.3 billion bases

8.0b

5.7b

3.5b

Danio rerio

Zea mays

2.5b

1.8b

Oryza sativa (japonica) 1.5b

Strongylocentrotus purpurata 1.2b

Sus scrofa 1.0b

Xenopus tropicalis 1.0b

Updated 7-19-06

GenBank release 154.0

Table 2-2

Page 18

Molecular Biology Information -

DNA

• Raw DNA Sequence

– Coding or Not?

– Parse into genes?

– 4 bases: AGCT

– ~1 K in a gene,

~2 M in genome

– ~3 Gb Human atggcaattaaaattggtatcaatggttttggtcgtatcggccgtatcgtattccgtgca gcacaacaccgtgatgacattgaagttgtaggtattaacgacttaatcgacgttgaatac atggcttatatgttgaaatatgattcaactcacggtcgtttcgacggcactgttgaagtg aaagatggtaacttagtggttaatggtaaaactatccgtgtaactgcagaacgtgatcca gcaaacttaaactggggtgcaatcggtgttgatatcgctgttgaagcgactggtttattc ttaactgatgaaactgctcgtaaacatatcactgcaggcgcaaaaaaagttgtattaact ggcccatctaaagatgcaacccctatgttcgttcgtggtgtaaacttcaacgcatacgca ggtcaagatatcgtttctaacgcatcttgtacaacaaactgtttagctcctttagcacgt gttgttcatgaaactttcggtatcaaagatggtttaatgaccactgttcacgcaacgact gcaactcaaaaaactgtggatggtccatcagctaaagactggcgcggcggccgcggtgca tcacaaaacatcattccatcttcaacaggtgcagcgaaagcagtaggtaaagtattacct gcattaaacggtaaattaactggtatggctttccgtgttccaacgccaaacgtatctgtt gttgatttaacagttaatcttgaaaaaccagcttcttatgatgcaatcaaacaagcaatc aaagatgcagcggaaggtaaaacgttcaatggcgaattaaaaggcgtattaggttacact gaagatgctgttgtttctactgacttcaacggttgtgctttaacttctgtatttgatgca gacgctggtatcgcattaactgattctttcgttaaattggtatc . . .

. . . caaaaatagggttaatatgaatctcgatctccattttgttcatcgtattcaa caacaagccaaaactcgtacaaatatgaccgcacttcgctataaagaacacggcttgtgg cgagatatctcttggaaaaactttcaagagcaactcaatcaactttctcgagcattgctt gctcacaatattgacgtacaagataaaatcgccatttttgcccataatatggaacgttgg gttgttcatgaaactttcggtatcaaagatggtttaatgaccactgttcacgcaacgact acaatcgttgacattgcgaccttacaaattcgagcaatcacagtgcctatttacgcaacc aatacagcccagcaagcagaatttatcctaaatcacgccgatgtaaaaattctcttcgtc ggcgatcaagagcaatacgatcaaacattggaaattgctcatcattgtccaaaattacaa aaaattgtagcaatgaaatccaccattcaattacaacaagatcctctttcttgcacttgg

Molecular Biology Information:

Protein Sequence

• 20 letter alphabet

– ACDEFGHIKLMNPQRSTVWY but not BJOUXZ

• Strings of ~300 aa in an average protein (in bacteria),

~200 aa in a domain

• >1M known protein sequences (uniprot) d1dhfa_ LNCIVAVSQ NM GIGKNGDLPW PP LRNEFRYFQRMT TTSSVEGKQNLVIMGKKTWFSI d8dfr__ LNSIVAVCQ NM GIGKDGNLPW PP LRNEYKYFQRMT STSHVEGKQNAVIMGKKTWFSI d4dfra_ ISLIAALAV DR VIGMENAMPW NLPADLAWFKRNT L--------N KPVIMGRHTWESI d3dfr__ TAFLWAQDR DG LIGKDGHLPW HLPDDLHYFRAQT V--------G KIMVVGRRTYESF d1dhfa_ LNCIVAVSQ NM GIGKNGDLPW PP LRNEFRYFQRMT TTSSVEGKQNLVIMGKKTWFSI d8dfr__ LNSIVAVCQ NM GIGKDGNLPW PP LRNEYKYFQRMT STSHVEGKQNAVIMGKKTWFSI d4dfra_ ISLIAALAV DR VIGMENAMPW -N LPADLAWFKRNT LD-------KPVIMGRHTWESI d3dfr__ TAFLWAQDR NG LIGKDGHLPW -H LPDDLHYFRAQT VG-------KIMVVGRRTYESF d1dhfa_ VPEKNRP LKGRINLVLS RELKEP PQGA H FLSRSLDDALKLTE QPELANKVD MVWIVGGSSVYKEAM NHP d8dfr__ VPEKNRP LKDRINIVLS RELKEA PKGA H YLSKSLDDALALLD SPELKSKVD MVWIVGGTAVYKAAM EKP d4dfra_ ---G-RP LPGRKNIILS -SQPGT DDRV TWVKSVDEAIAACG DVP-----EIMVIGGGRVYEQFL PKA d3dfr__ ---PKRP LPERTNVVLT HQEDYQ AQGA VVVHDVAAVFAYAK QHLDQ---ELVIAGGAQIFTAFK DDV d1dhfa_ -PEKNRP LKGRINLVLS RELKEP PQGA H FLSRSLDDALKLTE QPELANKVD MVWIVGGSSVYKEAM NHP d8dfr__ -PEKNRP LKDRINIVLS RELKEA PKGA H YLSKSLDDALALLD SPELKSKVD MVWIVGGTAVYKAAM EKP d4dfra_ -G---RP LPGRKNIILS SSQPGT DDRV TWVKSVDEAIAACG DVPE----.IMVIGGGRVYEQFL

PKA d3dfr__ -P--KRP LPERTNVVLT HQEDYQ AQGA VVVHDVAAVFAYAK QHLD----Q ELVIAGGAQIFTAFK DDV

Molecular Biology Information:

Macromolecular Structure

• DNA/RNA/Protein

– Almost all protein

(RNA Adapted From D Soll Web Page,

Right Hand Top Protein from M Levitt web page)

Molecular Biology

Information:

Whole Genomes

• The Revolution Driving

Everything

Fleischmann, R. D., Adams, M. D., White, O., Clayton, R. A., Kirkness, E.

F., Kerlavage, A. R., Bult, C. J., Tomb, J. F., Dougherty, B. A., Merrick, J.

M., McKenney, K., Sutton, G., Fitzhugh, W., Fields, C., Gocayne, J. D.,

Scott, J., Shirley, R., Liu, L. I., Glodek, A., Kelley, J. M., Weidman, J. F.,

Phillips, C. A., Spriggs, T., Hedblom, E., Cotton, M. D., Utterback, T. R.,

Hanna, M. C., Nguyen, D. T., Saudek, D. M., Brandon, R. C., Fine, L. D.,

Fritchman, J. L., Fuhrmann, J. L., Geoghagen, N. S. M., Gnehm, C. L.,

McDonald, L. A., Small, K. V., Fraser, C. M., Smith, H. O. & Venter, J. C.

(1995). "Whole-genome random sequencing and assembly of Haemophilus influenzae rd." Science 269: 496-512.

(Picture adapted from TIGR website, http://www.tigr.org)

• Integrative Data

1995, HI (bacteria): 1.6 Mb & 1600 genes done

1997, yeast: 13 Mb & ~6000 genes for yeast

1998, worm: ~100Mb with 19 K genes

1999: >30 completed genomes!

2003, human: 3 Gb & 100 K genes...

Genome sequence now accumulate so quickly that, in less than a week, a single laboratory can produce more bits of data than

Shakespeare managed in a lifetime, although the latter make better reading.

-- G A Pekso, Nature 401 : 115-116 (1999)

1995

Bacteria,

1.6 Mb,

~1600 genes

[ Science 269 : 496]

1997

Eukaryote,

13 Mb,

~6K genes

[Nature 387 : 1]

1998

Animal,

~100 Mb,

~20K genes

[ Science 282 :

1945]

2000?

Human,

~3 Gb,

~100K genes

[???]

Genomes highlight the Finiteness of the “Parts” in

Biology real thing, Apr ‘00

‘98 spoof

Cor e

Other Types of Data

• Gene Expression

– Early experiments yeast

– Now tiling array technology

• 50 M data points to tile the human genome at ~50 bp res.

– Can only sequence genome once but can do an infinite variety of array experiments

• Phenotype Experiments

• Protein Interactions

– For yeast: 6000 x 6000 / 2 ~ 18M possible interactions

– maybe 30K real

Weber

Cartoon

Bioinformatics is born!

(courtesy of Finn Drablos)

Major Application I:

Designing Drugs

• Understanding How Structures Bind Other

Molecules (Function)

• Designing Inhibitors

• Docking, Structure Modeling

Cor e

(From left to right, figures adapted from Olsen Group Docking Page at Scripps, Dyson NMR Group Web page at Scripps, and from Computational

Chemistry Page at Cornell Theory Center).

Major Application II: Finding

Homologs

Cor e

Major Application II:

Finding Homologues

• Find Similar Ones in Different Organisms

• Human vs. Mouse vs. Yeast

– Easier to do Expts. on latter!

(Section from NCBI Disease Genes Database Reproduced Below.)

Human Genes and S. cerevisiae Proteins

Human Disease MIM # Human GenBank BLASTX Yeast GenBank Yeast Gene

Gene Acc# for P-value Gene Acc# for Description

Human cDNA Yeast cDNA

Hereditary Non-polyposis Colon Cancer 120436 MSH2 U03911 9.2e-261 MSH2 M84170 DNA repair protein

Hereditary Non-polyposis Colon Cancer 120436 MLH1 U07418 6.3e-196 MLH1 U07187 DNA repair protein

Cystic Fibrosis 219700 CFTR M28668 1.3e-167 YCF1 L35237 Metal resistance protein

Wilson Disease 277900 WND U11700 5.9e-161 CCC2 L36317 Probable copper transporter

Glycerol Kinase Deficiency 307030 GK L13943 1.8e-129 GUT1 X69049 Glycerol kinase

Bloom Syndrome 210900 BLM U39817 2.6e-119 SGS1 U22341 Helicase

Adrenoleukodystrophy, X-linked 300100 ALD Z21876 3.4e-107 PXA1 U17065 Peroxisomal ABC transporter

Ataxia Telangiectasia 208900 ATM U26455 2.8e-90 TEL1 U31331 PI3 kinase

Amyotrophic Lateral Sclerosis 105400 SOD1 K00065 2.0e-58 SOD1 J03279 Superoxide dismutase

Myotonic Dystrophy 160900 DM L19268 5.4e-53 YPK1 M21307 Serine/threonine protein kinase

Lowe Syndrome 309000 OCRL M88162 1.2e-47 YIL002C Z47047 Putative IPP-5-phosphatase

Neurofibromatosis, Type 1 162200 NF1 M89914 2.0e-46 IRA2 M33779 Inhibitory regulator protein

Choroideremia 303100 CHM X78121 2.1e-42 GDI1 S69371 GDP dissociation inhibitor

Diastrophic Dysplasia 222600 DTD U14528 7.2e-38 SUL1 X82013 Sulfate permease

Lissencephaly 247200 LIS1 L13385 1.7e-34 MET30 L26505 Methionine metabolism

Thomsen Disease 160800 CLC1 Z25884 7.9e-31 GEF1 Z23117 Voltage-gated chloride channel

Wilms Tumor 194070 WT1 X51630 1.1e-20 FZF1 X67787 Sulphite resistance protein

Achondroplasia 100800 FGFR3 M58051 2.0e-18 IPL1 U07163 Serine/threoinine protein kinase

Menkes Syndrome 309400 MNK X69208 2.1e-17 CCC2 L36317 Probable copper transporter

Major Application I|I:

Cor e

Overall Genome Characterization

• Overall Occurrence of a

Certain Feature in the

Genome

– e.g. how many kinases in Yeast

• Compare Organisms and Tissues

– Expression levels in Cancerous vs

Normal Tissues

• Databases, Statistics

(Clock figures, yeast v. Synechocystis, adapted from GeneQuiz Web Page, Sander Group, EBI)

What do you get from largescale data mining? Global statistics on the population of proteins

EX-1: Occurrence of

EX-2: Occurrence of 1-4 functions per fold & salt bridges in genomes interactions per fold of thermophiles v over all genomes mesophiles

0.70

0.60

0.50

0.40

0.30

0.20

0.10

0.00

EK(3)

EK(4)

MP MG EC SC HP SS HI MT MJ AF AA OT

10 to 45 65 85 83 95

Mesophile Thermophile

Physiological temperature in C

98

http://www.nature.com/nature/journal/vaop/ncurrent/pdf/ nature07331.pdf

End of First Lecture

2009

Remaining Slides

Lecture 2

Organizing

Molecular Biology

Information:

Redundancy and

Multiplicity

• Different Sequences Have the Same

Structure

• Organism has many similar genes

• Single Gene May Have Multiple

Functions

• Genes are grouped into Pathways

• Genomic Sequence Redundancy due to the Genetic Code

How do we find the similarities?....

Cor e

Integrative Genomics genes

 structures

 functions

 pathways

 expression levels

 regulatory systems

 ….

Ome molecular group

Genome

Proteome

Transcriptome

Phenome

Interactome

Metabolome

Physiome

Orfeome

Secretome

Morphome

Glycome

Regulome

Functome

Cellome

Transportome

Ribonome

Operome

'Omics: studying populations of molecules in a database framework

Ome molecular group

Genome

Proteome

Transcriptome

Phenome

Interactome

Metabolome

Physiome

Orfeome

Secretome

Morphome

Glycome

Regulome

Functome

Cellome

Transportome

Ribonome

Operome

Google

Hits

58200000

1850000

707000

418000

87500

80700

56300

29800

23900

11400

995

618

390

246

155

131

57

'Omics: studying populations of molecules in a database framework

Ome molecular group

Genome

Proteome

Transcriptome

Phenome

Interactome

Metabolome

Physiome

Orfeome

Secretome

Morphome

Glycome

Regulome

Functome

Cellome

Transportome

Ribonome

Operome

Cor e

PubMed

Hits

48

2

34

6

1

17

1

1

0

537993

6005

1665

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Google

Hits

23900

11400

995

618

390

246

155

131

57

58200000

1850000

707000

418000

87500

80700

56300

29800

PubMed

First year

1953

1995

1997

1989

1999

1998

1997

2002

2000

2000

2000

2004

2001

2002

2004

2002

'Omics: studying populations of molecules in a database framework

Proteome

A Parts List Approach to Bike

Maintenance

Extra

A Parts List Approach to Bike

Maintenance

How many roles can these play?

How flexible and adaptable are they mechanically?

What are the shared parts ( bolt , nut , washer , spring , bearing ), unique parts ( cogs, levers )? What are the common parts -

- types of parts

( nuts & washers )?

Cor e

Extra

Where are the parts located?

Molecular Parts = Conserved

Domains, Folds, &c

Total in Databank

New Submissions

New Folds

Vast Growth in

(Structural) Data...

but number of

Fundamentally New (Fold)

Parts Not Increasing that Fast

World of Structures is even more Finite, providing a valuable simplification

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 … ~100000 genes

~1000 folds

(human)

(T. pallidum)

1 2 3 4 5 6 7 8 9 10 11

Same logic for pathways, functions, sequence families, blocks, motifs....

Global Surveys

of a

Finite Set of Parts

from

Many Perspectives

Functions picture from www.fruitfly.org/~suzi (Ashburner); Pathways picture from, ecocyc.pangeasystems.com/ecocyc (Karp, Riley). Related resources: COGS, ProDom,

Pfam, Blocks, Domo, WIT, CATH, Scop....

12 13 14 15 …

~1000 genes

What is Bioinformatics?

• (Molecular)

Bio informatics

• One idea for a definition?

Bioinformatics is conceptualizing biology in terms

of molecules (in the sense of physical-chemistry) and then applying “informatics” techniques

(derived from disciplines such as applied math, CS, and statistics) to understand and organize the information associated with these molecules, on a large-scale.

• Structural Bioinformatics is a practical discipline with many applications that deals with biological three dimensional structural data.

General Types of

“Informatics” techniques

• Databases

in Bioinformatics

• Geometry

 Building, Querying

 Object DB

• Text String Comparison

 Text Search

 1D Alignment

 Significance Statistics

 Google, grep

• Finding Patterns

 AI / Machine Learning

 Clustering

 Datamining

 Robotics

 Graphics (Surfaces, Volumes)

 Comparison and 3D Matching

(Vision, recognition)

• Physical Simulation

 Newtonian Mechanics

 Electrostatics

 Numerical Algorithms

 Simulation

Bioinformatics Topics --

Genome Sequence

• Finding Genes in Genomic

DNA

 introns

 exons

 promotors

• Characterizing Repeats in

Genomic DNA

 Statistics

 Patterns

• Duplications in the Genome

 Large scale genomic alignment

• Whole-Genome Comparisons

• Finding Structural RNAs

• Sequence Alignment

 non-exact string matching, gaps

 How to align two strings optimally via Dynamic

Programming

 Local vs Global Alignment

 Suboptimal Alignment

 Hashing to increase speed

(BLAST, FASTA)

 Amino acid substitution scoring matrices

• Multiple Alignment and

Consensus Patterns

 How to align more than one sequence and then fuse the result in a consensus representation

 Transitive Comparisons

 HMMs, Profiles

 Motifs

Bioinformatics

Topics --

Protein Sequence

• Scoring schemes and

Matching statistics

 How to tell if a given alignment or match is statistically significant

 A P-value (or an e-value)?

 Score Distributions

(extreme val. dist.)

 Low Complexity Sequences

• Evolutionary Issues

 Rates of mutation and change

Bioinformatics

Topics --

Sequence /

Structure

• Secondary Structure

“Prediction”

 via Propensities

 Neural Networks, Genetic

Alg.

 Simple Statistics

 TM-helix finding

 Assessing Secondary

Structure Prediction

• Structure Prediction:

Protein v RNA

• Tertiary Structure Prediction

 Fold Recognition

 Threading

 Ab initio

• Function Prediction

 Active site identification

• Relation of Sequence Similarity to

Structural Similarity

Problems in Protein Bioinformatics

• Prediction of structure from sequence

 Fold recognition

 Fragment construction

• Proteome annotation

• Protein-protein docking

Protein sequence

Protein folding code

Protein folding code

Protein structure

Prediction of correct fold

Query sequence

Fold recognitio n

Matched fold

Match sequence against library of known folds

Eisenberg et al.

Jones, Taylor, Thornton

Computational Requirements

• 1 sequence search takes 12 mins (3Ghz)

• Benchmarking on 100 proteins with 100 runs for a simplex search of parameter space = 80 days

• 30 approaches explored = 7 years (on 1 cpu)

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