The document provides an overview of microRNAs (miRNAs), discussing their structure, biogenesis, conservation, and role in gene regulation. It highlights the therapeutic potential of miRNAs in cancer treatment and emphasizes the need for further research to harness their capabilities in medical applications. The historical context of miRNA discovery and their impact on protein expression are also explored.

1. microRNA “miRNA”
Omoyayi Ibrahim O.
PhD Biomedical Engineering (in view)
omodammy@gmail.com

2. Outline
• DNA and RNA Structure
• Central Dogma of Life
• Protein Engineering (Brief)
• Introduction to microRNA (miRNA)
• History of miRNA
• Biogenesis of miRNA
• Conservation of miRNA
• Impact of miRNA
• miRNA Therapy
• Conclusion

3. STRUCTURE OF DNA AND RNA
Google Images

4. An Overview

5. Central Dogma of Life
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Replication
Transcription Translation
Translation in Eukaryotes is quite
complicated
Splicing of genes(s) occurs ^^^
Protein Engineering
2%
98%
mRNA or RNAi

6. miRNA
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• miRNAs are non-coding RNAs in hair pin-like
structure found only in Eukaryotes
• Single stranded and small in size (˷22 nt
long). It folds back on itself
• Comprise one of the more classes of gene
regulatory molecules
• Play important regulatory roles in by
targeting mRNAs for cleavage or
translational repression
• One miRNA can bind to more than one
mRNA (Vice versa)
• Aberrant level of mRNA is controlled by
miRNA

7. History of miRNA
• miRNA was first discovered in 1993 during a study of the lin-4 gene in
the study of C. elegans.
• Also in 2000, let-7 RNA was regulated lin-41mRNA (L4) to Adult.
• Researchers realized several small regulating RNA were present in C.
elegans, Drosophila and human cells. Hence named miRNA

8. History of miRNA
Lagos-Quintana et al., Science 2001
Lau et al., Science 2001
Lee & Ambros., Science 2001

9. miRNA Biogenesis
Source: David Bartel (Whitehead Institute/MIT/HHMI)
In the nucleus
In the cytoplasm

10. siRNA Biogenesis
Source: David Bartel (Whitehead Institute/MIT/HHMI)
A long strand may fold
on itself to form
dsRNA
Two complementary
micro RNA may bind
Often Silence the
same type of loci
Gene K.O

11. miRNA Conservation
Source: David Bartel (Whitehead Institute/MIT/HHMI)
miR-1 found in muscle cells

12. miRNA Conservation
Source: David Bartel (Whitehead Institute/MIT/HHMI)
miR-1 found in muscle cells

13. miRNA Impact
Emery et all., 2004 Curr. Biol. 2003
The Regulation of the Phabulosa mRNA by miRNA 166 is very important.
Other micro RNAs regulate other protein expression significantly

14. miRNA Target Recognition
^Gene Silencing ^Gene K.O
miRNA Target Degradation

15. miRNA on mRNA Protein Expression
 Some mRNA are turned off, Some are expressed at high or low level.
 mRNA has been noticed to be tagged with specific sites to allow complexity of
expression.
 This fine-tuning of the complexity of gene expressions from the optimum amount of
protiens give rise to us as a whole

16. Importance of miRNAs - Experiment
Using Zebra fish

17. microRNA Therapeutics in Cancer — An Emerging
Concept Maitri Y. Shah,a Alessandra Ferrajoli,b Anil K Sood,c Gabriel Lopez-Berestein,d and George A. Caline,
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5078622/

18. microRNA Therapeutics in Cancer — An Emerging
Concept Maitri Y. Shah,a Alessandra Ferrajoli,b Anil K Sood,c Gabriel Lopez-Berestein,d and George A. Caline,
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5078622/

19. microRNA Therapeutics
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4840794/

20. microRNA Therapeutics
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5078622/

21. microRNA Therapeutics
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5078622/

22. microRNA Therapeutics
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5078622/

23. Using Zebra fish
https://www.nature.com/articles/bjc2016379.pdf

24. The functionality of miRNA in controlling diverse gene
expression makes miRNA an ideal candidate for therapeutic
applications.
Recent study demonstrate that the miRNA expression is
altered in various human diseases and its selective modulation
through antisense inhibition or replacement could significantly
affect the prognosis of a disease.
Recent technological advancement and ease of administration
of miRNA gives miRNA therapeutics an extra edge.
I hope that the increasing research and development on
miRNA will increase miRNA therapeutics in the market in the
coming years for the treatment of various diseases.
Conclusions

25. Thank You.
Question(s)?