A presentation of Polymerase chain reaction prepared by student of JUST

1. WELLCOME TO OUR PRESENTATION
Presented by-
Md. Mohaimenul (111001)
Tamal Baulia (111009)
Koushik Ahmed (111011)
Fouzia Afroz (111020)
Jessore University of Science &
Technology,jessore,Bangladesh.
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2. A Presentation
On
*Polymerase chain reaction(PCR)
*Antisense therapy
*Complement system
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3. Content:
• Polymerase chain reaction (definition, steps,
application)
• Antisense therapy (definition, working,
application)
• Complement system (definition, ways,
pathway)
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4. Polymerase chain reaction
PCR, polymerase chain reaction, is an in-vitro
technique for amplification of a region of DNA
whose sequence is known or which lies
between two regions of known sequence[1].
It was invented in 1983 by Dr. Kary Mullis, for
which he received the Nobel Prize in
Chemistry in 1993 [2].
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5. Basic component of PCR
 Target DNA - contains the sequence to be amplified.
 Pair of Primers - oligonucleotides that define the sequence
to be amplified.
 dNTPs - deoxynucleotidetriphosphates: DNA building blocks.
 Thermostable DNA Polymerase - enzyme that catalyzes the
reaction
 Mg++ ions - cofactor of the enzyme
 Buffer solution – maintains pH and ionic strength of the
reaction solution suitable for the activity of the enzyme [3].
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6. Steps involve in PCR
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1.DNA denaturation
2.DNA Annealing
3.Extension [3]

7. Application of PCR
Genome mapping and gene function
determination
Biodiversity studies ( e.g. evolution studies)
Diagnostics ( prenatal testing of genetic
diseases, early detection of cancer, viral
infections...)
Detection of drug resistance genes
Forensic (DNA fingerprinting) [2]
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8. Antisense therapy
Antisense therapy refers to the inhibition of
translation by using a single stranded
nucleotide (antisense oligonucleotide) [2]
It inhibits both transcription and translation
by blocking transcription factor responsible for
the specific gene expression [2]
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9. Working
9[4]

10. Application :
Antisense therapy use to treat-
Myeloid leukemia
Brain tumor
Malignant glioma
Prostate cancer
Viral and parasitic infection
Inflammatory diseases [2]
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11. Complement system
• A complex consisting of at least 20 serum
proteins, which, once activated, acts like a
part of the innate immune defense.
• The complement components are present in
serum in inactive form.
• Complement proteins are synthesized mainly
in the liver, but tissue macrophages and
fibroblasts can synthesize some complement
proteins as well [2].
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12. Ways of complement reaction
• Complement fixation
• Opsonization
• Inflammatory reaction
• Clearance of antigen-antibody complex [2].
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13. Pathway of complement system
• The complement pathway can be activated by either
of two different pathways.
– Classical pathway (specific immune system)
– alternative (non-specific immune system) [2].
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14. The Classical Pathway
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The classical pathway is considered to be
part of the specific immune response because
it relies on antibodies to initiate it.
C1 becomes activated when it binds to the
ends of antibodies.
Once C1 is activated, it activates 2 other
complement proteins, C2 and C4 by cutting
them in half
C2 is cleaved into C2a and C2b
C4 is cleaved into C4a and C4b
Both C2b and C4b bind together on the
surface of the bacteria
C2a and C4a diffuse away [1].

15. The alternative pathway
• The alternative pathway is part of the non-
specific defense because it does not need
antibodies to initiate the pathway.
• The alternative pathway is slower than the
Classical pathway [2].
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16. The Alternative
complement pathway
16[1]

17. Have any question
????????
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18. References:
[1].Fundamentals of Biochemistry ( Voet, Voet,
Pratt)
[2].Biochemistry (U. Satyanarayana, U.
Chakrapani)
[3].Molecular Cell Biology ( Lodish, Darnell..)
[4]. Molecular & Cell Biology of Cancer (Knowles
and Selby)
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19. Thanks for your kind
attention & co-
operation
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