transposable genetic mateial are also known as jumping genes and they play very important role in the evolution of species.

1. Transposable Genetic Material and
their role in Evolution of Specie
Submitted by : Nasira Bashir
Roll# 1
112/11/2014 TE and their role in evolution of species

2. CONTENT
• Introduction
• Discovery
• Properties of TE
• Classification of TE
• Effect of transposons
• Applications of transposons
• Role of TE in evolution
• Conclusion
• References
212/11/2014 TE and their role in evolution of species

3. Transposable genetic elements
• They are segments of DNA which are able to “jump”
from location to location within a genome. This
"jumping" process is called transposition.
• Each transposable element carries transposase gene
that encodes for enzyme activity required for its own
transposition
3
TRANSPOSONS
Jumping
genes
Mobile
genetic
elements
12/11/2014 TE and their role in evolution of species

4. These six lab mice illustrate a transposon's
ability to affect the genome
schematic diagram of transposition
between two prokaryotic plasmids
4
Transposable genetic elements
12/11/2014 TE and their role in evolution of species

5. DISCOVERY
• The Nobel Prize in Physiology
or Medicine 1983 was awarded
to Barbara McClintock "for
her discovery of mobile
genetic elements".
• She discovered TEs by
analyzing genetic stocks of
corn that were phenotypically
unstable
• The instability involves
chromosome breakage and was
found to occur at sites where
transposable elements were
located i.e. at C locus of 9th
chromosome.
512/11/2014 TE and their role in evolution of species

6. Internal structure of maize
612/11/2014 TE and their role in evolution of species

7. • Genes Studied by McClintock
• CI = dominant allele that prevents color from being
expressed in the aleurone layer
• C = recessive allele that leads to color development in
the aleurone layer
• Bz = dominant allele that produces purple aleurone
color
• bz = recessive allele that produces a dark brown to
purple-brown aleurone color
• Ds = a genetic location where chromosome breakage
occurs
7
Experiment
12/11/2014 TE and their role in evolution of species

8. 8
Experiment
12/11/2014 TE and their role in evolution of species

9. Results of experiment and
observations
• Ds requires some factor
provided by Ac to move,
whereas Ac is independent
• Because of their
relationship, Ac is termed an
autonomous element and
Ds a non-Autonomous
element.
• Because both Ac and Ds can
move, they are called
transposable genetic
elements
9
No autonomous elements
Gene(s)
Autonomous
12/11/2014 TE and their role in evolution of species

10. • the molecular features of
the maize Ac/Ds system
are:
• Ac is 4563 bp in length
• contain 11-bp inverted
repeats at the ends
• 8-bp direct repeats of
target DNA are generated
• Ds are truncated versions
of Ac
10
Results of experiment and
observations
12/11/2014 TE and their role in evolution of species

11. Properties of transposable elements
• Mobility
• Considerable diversity.
• Transposable elements effectively insert at staggered breaks in
chromosomes.
• Major forces in the evolution and rearrangement of genomes
• Transposable elements can cause deletions or inversions of
DNA
1112/11/2014 TE and their role in evolution of species

12. Classification of TEs:
Class I (Retrotransposons) Class II (DNA Transposons)
• simplest transposons
• It transfer through the non-
replicative transposition
mechanism
• Doesn’t produce multiple
copies
• prokaryotic transposons as
well as some eukaryotic
transposons
• e.g. Ds and Ac
12
• complex transposons
• It transfer through the
replicative transposition
mechanism
• produce multiple copies of the
retrotransposon within genome
• Two main types
• Viral retrotransposon
• Non-viral retrotransposon
• majority of eukaryotic
transposons
12/11/2014 TE and their role in evolution of species

13. Replicative transposition
1312/11/2014 TE and their role in evolution of species

14. Conservative transposition
1412/11/2014 TE and their role in evolution of species

15. Types of Retrotransposons
Viral retrotransposon
• Viral retrotransposons have
properties similar to that of
retroviruses.
• Ty Transposable Elements can
be found within the yeast
genome
• The Drosophilacopia
transposable element
• There are seven known
families of Drosophilacopia
transposons within the fruit fly
genome
Non-viral retrotransposons
• Non-viral retrotransposons
comprise the largest majority
of mammalian transposns.
• LINEs. Or long interspersed
(transposable) elements
• SINEs, or short
interspresed(transposable)
elements
• Alu elements are the most
common transposable
elements within the human
genome, making up more than
5%.
1512/11/2014 TE and their role in evolution of species

16. The Effects of Transposons
Gene Disorder Transposon
Insertion
Site
NFI Neurofibromatosis Intron
F9 Hemophilia B Exon
BRCA2 Breast cancer Exon
CASR Familial hypocalciuric
hypercalcemia
Exon
APC Hereditary desmoid
disease
Exon
GK Glycerol kinase deficiency Intron
CINH C1 inhibitor deficiency Intron
PBGD Acute intermittent
porphyria
Exon
FIX Hemophilia B Exon
1612/11/2014 TE and their role in evolution of species

17. Application of transposable element
1712/11/2014 TE and their role in evolution of species

18. TE in genetic engineering
Bicyclus anynana butterfly
Bicyclus anynana butterfly which
has modified
1812/11/2014 TE and their role in evolution of species

19. Major types of expression and mutagenic cassettes
delivered by transposon vectors for versatile applications
1912/11/2014 TE and their role in evolution of species

20. Role of Transposable genetic material in
evolution
• McDonald believed that plants and animals
were forced to evolve quickly in order to
defend their genome against dangerous
transposable elements
• McDonald believed that various species had
developed two important method of defence.
• Chromatin formation
• Methylation
2012/11/2014 TE and their role in evolution of species

21. Transposons and the Evolution of the
Immune System
• Geneticist David Schatz and colleagues at Yale
University
• 500 million years ago
• The RAG transposon is suspected to have emerged
within the genome of human ancestors roughly 450
million years ago.
• The RAG transposon codes for the protein which is
responsible for cleaving, recombining, and binding
the gene fragments required to synthesize antibody
sentinels.
2112/11/2014 TE and their role in evolution of species

22. Britten’s Theory of Evolution
• Biologist Roy Britten of Cal Tech claims that
transposition within the genome has had a much
more profound impact on evolution than the
common single base mutation.
• When a single base mutation occurs, the result is
often the production of a slightly altered protein.
• However, when a transposon moves to a new
location within a genome, it can alter entire patterns
of gene expression, which can drastically effect how
an organism develops.
2212/11/2014 TE and their role in evolution of species

23. Transposons in Primate Evolution
• Geneticist Wanda Reynolds believes that Alu
elements had an immense influence on the
evolution of primates, and humans.
2312/11/2014 TE and their role in evolution of species

24. Future Prospects for
Transposons in Research

25. References
• http://transposons.tripod.com/id5.html
• http://biowiki.ucdavis.edu/Genetics/Unit_II%3A_Replication,_Main
tenance_and_Alteration_of_the_Genetic_Material/9._Transpositio
n_of_DNA/Transposable_Elements
• http://www.ndsu.edu/pubweb/~mcclean/plsc431/transelem/trans
1.htm
• http://plato.acadiau.ca/courses/biol/Microbiology/transfer.htm
• https://www.mdc-
berlin.de/30144912/en/highlights/archive/2009/highlight5
• http://www.mobilednajournal.com/content/1/1/25
• http://www.eurekalert.org/pub_releases/1998-02/UoG-TEMH-
090298.php
• http://www.keystonesymposia.org/14C2
2512/11/2014 TE and their role in evolution of species