2. INTRODUCTION TO PROTEOMICS
Proteomics is simply defined as the Study of
Proteome. The term proteome was created by
Wasinger et al. (1995) and Wilkins et al. (1996) and
defined as the cell- and tissue-specific patterns of
proteins expressed by the genome of an organism.
Proteomics is also defined as the study of total
protein content of a cell or that of an organism.
3. SCOPE OF PROTEOMICS
Proteomics helps in understanding the alteration in
protein expression during different stages of life cycle or
under stress condition.
Proteomics is also important with regards to drug
development against several diseases and
understanding various biological processes, as proteins
are the most favourable targets for various drugs.
4. SCOPE OF PROTEOMICS
Proteomics helps in understanding the structure and
function of different proteins as well as protein-protein
interactions of an organism and a minor defect in either
protein structure, its function or alternation in
expression pattern can be easily detected using
proteomics studies.
Protein to gene can be predicted by Proteomics.
5. CLASSIFICATION OF PROTEOMICS
1. Functional Proteomics: Identifications of Protein-Protein,
Protein-DNA and Protein-RNA interactions affecting
function.
2. Structural Proteomics: Identification of all interactions by
metal ions, toxins, drugs etc. affecting Protein structure.
3. Differential Proteomics: Determination of differences in
Protein expression.
6. BIO-MOLECULAR IDENTIFICATION
Initial step in all proteomic studies is the separation of
proteins mixture by Two Dimensional Gel Electrophoresis
technique, based on their individual charges in 1D. The gel is
then turned 90 degrees to separate proteins based on the
difference in their size. This separation occurs in 2nd dimension
hence the name 2D. The spots obtained in 2D electrophoresis
are excised and further subjected to mass spectrometric analysis
of each protein present in the mixture.
7. STEPS IN PROTEOMIC ANALYSIS
Purification of proteins: It involves extraction of protein
sample followed by purification using density gradient
centrifugation, chromatographic techniques (affinity etc.)
Separation of proteins: 2D gel electrophoresis is applied for
separation of proteins on the basis of their isoelectric points in
one dimension and molecular weight on the other. Spots are
detected using fluorescent dyes or radioactive probes.
8. STEPS IN PROTEOMIC ANALYSIS
Identification of proteins: The separated protein spots
on gel are excised and digested in gel by a protease (e.g.
trypsin). The eluted peptides are identified using mass
spectrometry.
Validation of Proteins: Determined amino acid sequence
is finally compared with available database to validate the
proteins.
11. GENE THERAPY
Pathological changes within an organism arise from
protein alterations. Proteomics provides a powerful set of tools
for the large-scale study of protein expression. The identification
of such changes by proteomics is essential to define drug
targets, therapeutic proteins, and disease biomarkers. Gene
therapy, primarily based on the delivery of a “therapeutic” gene
to the diseased organ, is an approach whose effect is finally due
to the function of the therapeutic protein encoded by the
12. GENE THERAPY
“therapeutic” gene, proteomics provides the basis required for
the design and application of gene therapies. Because in certain
diseases the absence of certain cellular or biological factors, for
example Enzymes occur and it is may be due to a gene being
defective. Cancer, infectious diseases, cardiovascular diseases,
neurological disorders and some inherited conditions are among
the areas into which the Gene therapy research is being carried
out.
13. APPLICATIONS OF PROTEOMICS
1. For discovery of protein biomarkers.
2. In the Study of Tumor Metastasis.
3. In the Field of Neuro-trauma.
4. In disease diagnosis.
5. In Neurology.
6. In Treatment of Autoimmune disease.
7. In Nutrition Research.