Target identification and Validation tells about the how target is neccesary for new drug discovery and its development to reach into market for rare diseases.
Role of Target Identification and Target Validation in Drug Discovery Process
1. ROLE OF TARGET IDENTIFICATION AND TARGET
VALIDATION IN DRUG DISCOVERY
Presented by:-
Pallavi Duggal
M.Pharmacy (2nd Semester)
Department of Pharmacology
ISF College Of Pharmacy
Moga, Punjab
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2. CONTENT
Introduction of drug discovery
Need of Drug Discovery
Target Identification
Genomics
Proteomics
Bioinformatics
Target Validation
si Rna
Antisense oligonucleotide
Role of transgenic animals
References
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3. DRUG DISCOVERY
Drug Discovery is the process through which potential
new medicines are identified.
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4. PURPOSE OF DRUG DISCOVERY
Drug discovery initiates because there is a disease or
clinical condition without suitable medical products
available.
Rare diseases or orphan diseases.
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5. TARGET IDENTIFICATION
Target :- It is a cellular or molecular structures
involved in pathology which are responsible for disease.
They may be :-
1. Receptors
2. Enzyme
3. Nucleic acid
4. Hormone
5. Ion Channel
Target Identification :- It is the process of identifying
the direct molecular target i.e protein, nucleic acid.
It is aimed at finding the efficacy target of a drug.
It is the first step in drug discovery 5
6. TOOLS FOR TARGET IDENTIFICATION
Tools for
Target
identification
ProteomicsGenomics
Bioinformatics
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7. ROLE OF GENOMICS
Genome :-
It is an organism complete set of DNA.
Genomics :-
1. It is the field of science focusing on structure,
function, mapping of Genomes.
2. It is concerned with sequencing and analysis of an
organism genome. Types of
Genomics
Structural
Genomics
Functional
Genomics
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8. STRUCTURAL GENOMICS
It is used to describe 3- D structure of every protein
encoded by a given genome.
It has potential to inform knowledge of protein function.
It characterize genome structures.
Attempts to determine structure of every protein encoded
by genome rather than focusing on one particular protein.
Various techniques used to determine structure of genome:-
De novo methods
Sequence based Modeling
Shortgun Sequencing 8
9. FUNCTIONAL GENOMICS
Focus on gene transcription, translation, regulation of
gene expression and protein- protein interactions.
Goal is to understand relationship between an organism
genome and its phenotype.
Measure all gene products like mRNA or proteins within
biological sample.
Technique used:-
DNA Microarray
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11. PROTEOMICS
Proteome :- Entire complement of proteins expressed by
a cell,tissue or organism.
Proteomics :- large scale study of protein and their
functions.
Techniques to do Proteomics:-
2D Electrophoresis
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12. CONTD...
Protein Microarray
High throughput method used to track the interactions
& activities of proteins and to determine their
functions.
Method
Proteins are immobilised on slides then they are
probed for variety of functions.
Probe are labelled with fluoroscent dyes.
When probe bind to protein gives fluoroscent signal.
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14. BIOINFORMATICS
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Bioinformatics has become an important part of many areas of biology. In
experimental molecular biology, bioinformatics techniques such
as image and signal processing allow extraction of useful results from large
amounts of raw data. In the field of genetics and genomics, it aids in sequencing
and annotating genomes and their observed mutations.
15. TARGET VALIDATION
Target validation is the process by which the predicted
molecular target – for example protein or nucleic acid –
of a small molecule is verified.
Target validation can include knockdown or
overexpression of the presumed target.
Tools for Target Validation
Antisense technologies
si RNA
Antisense
Oligonucleotides
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16. SI RNA
Small (or short) interfering RNA (siRNA) is the commonly used
forRNA interference (RNAi) tool for inducing short-term
silencing of protein coding genes.
It is a double stranded RNA molecule which interferes with
the expression of specific genes by degrading mRNA after
transcription & preventing translation.
siRNA is double stranded RNA(dsRNA). It consist of two RNA
strands, an antisense (or guide) strand and a sense (or passenger)
strand, which form a duplex
20-24 bp length.
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17. MECHANISM
long dsRNA is cleaved by
an endo-ribonuclease
called Dicer to form short
interfering RNA or
siRNA.
siRNA enters the cell and
binds to Argonaute
protein to form RISC.
siRNA is then unwinded
to form single stranded
siRNA.
si rna and RISC complex
find their complementary
mRNA
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18. ANTISENSE OLIGONUCLEOTIDE
Antisense technology prevent the synthesis of specific
protein.
AS- ONS;15-20 nucleotides which are complementary to
their target mRNA.
When these AS-ON combined with target mRNA, a
DNA/RNA hybrid form which degraded by the enzyme
RNase H.
RNase H is a non specific endonuclease which catalyse
cleavage of RNA.
RNase H has ribonuclease activity cleaves the 3’-O-P
bond of RNA in a DNA/RNAduplex.
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21. ROLE OF TRANSGENIC ANIMALS
Transgenic animals are animals that have a foreign gene
deliberately inserted into their genome.
Methods to insert transgenes
Microinjection
Embryonic stem cell
Retroviral vector method 21
22. CONTD...
Working example:-
Target identification
Suppose we identify disease
ie Alzeimer
Translated this disease
model into animals.
Animal model of
AD(Streptozocin used to
induce beta amyloid protein
in hippocampus. 22
23. Target identification by proteomics and genomics.
Overexpression of APP protein is responsible for disease.
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24. Target Validation :-
Validate that really
APP is responsible for
AD.
Deliver mutant APP
gene into animal
Progenies having
mutant APP gene
overexpressed
Target validated 24
25. REFERENCES
Michael J.,Israel S.,et al. 1995“The importance of
genome analysis to the drug discovery process” Journal
of Molecular Medicine Today. Volume 1, Pages 373-377.
Yeakuty M.J,. Mohammad F.K.,et al.2012 “Proteomics
in Drug Discovery” Journal of Applied Pharmaceutical
Science02(08),Pg1-12.
Blake RA, 2007 “Target validation in drug discovery”
Journal of Methods Mol Biology,Pg 367-77.
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