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 1
- 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 2
- 3. DRUG DISCOVERY Drug Discovery is the process through which potential new medicines are identified. 3
- 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. 4
- 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 6
- 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 7
- 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 9
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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 11
- 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. 12
- 13. CONTD... Types of microarray Analytical Microarray Functional Protein Microarray Reverse Phase Protein Microarray 13
- 14. BIOINFORMATICS 14 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 15
- 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. 16
- 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 17
- 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. 18
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- 20. MECHANISM OF ANTISENSE OLIGONUCLEOTIDE 20
- 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. 23
- 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. 25
- 26. 26 THANK YOU