DNA repair mechanisms are indispensable for cell maintenance. The most common repair mechanisms are base excision repair (BER) and nucleotide excision repair (NER). Deficiencies in repair can lead to diseases like cancer or myelodysplastic syndrome. Studies have found that some viruses like murine polyomavirus activate DNA damage repair proteins like ATR and MRE11 to promote viral replication. Understanding DNA repair is important for developing new treatments for diseases linked to repair deficiencies and viral infections.

1. DNA
REPAIR
MECHANISMS
MARÍA CAMILA OCAMPO YEPES
MEDICINE STUDENT
2016

2. DNA REPAIR
MECHANISM
S
CREATED BY: María Camila
Ocampo Yepes
MOLECULAR BIOLOGY
TEACHER: Lina Martínez
MEDICAL UTILITY
Many pathologies are
associated with deficient repair
mechanisms , because this
condition can modify the normal
cell process.
The most common example is
cancer, in this disease, the cell
loses the capacity of recognize
and repair the damaged DNA
and continues with the cell
cycle, allowing a mutagenic
proliferation.
In order to predict and create an
effective treatment for these
conditions, the actual
investigations are focus on
innumerable topics about DNA
damaged repair.
BIBLIOGRAPHY
• MARTINEZ SÁNCHEZ, Lina María.
Biología molecular. 8. ed. Medellín:
UPB. Fac. de Medicina, 2015. 109-
115 p.
• Federal University of Ceara. (2016,
July 22). Influence of functional
polymorphisms in DNA repair genes
of myelodysplastic syndrome.
Leukemia Research. Retrieved
August 28, 2016 from
http://www.sciencedirect.com.consu
ltaremota.upb.edu.co/science/article
/pii/S0145212616301400
• Developmental Biology and
BioFrontiers Institute; University of
Colorado. (2016, July 26). Activation
of DNA damage repair pathways by
murine polyomavirus. Virology.
Retrieved August 28, 2016 from
http://www.sciencedirect.com.consu
ltaremota.upb.edu.co/science/article
/pii/S0042682216302021

3. Influence of functional
polymorphisms in DNA repair
genes of myelodysplastic
syndrome
The myelodysplastic syndrome is a group
of diseases characterized by multiple
cytopenias, as a consequence of an altered
stem cell in the marrow bone.
Researchers at Federal University of
Ceara, discovered several polymorphisms
associated with the deficient of DNA repair
Mechanisms that cause this pathology.
My point of view
the relation between polymorphisms of
specific genes and the
myelodysplastic syndrome,
represents a new scientific
field for its diagnosis and
treatment. For this reason
the study of the implicated
genes in these diseases, is
a significant opportunity
for a future genetic therapy.
INTRODUCTION
The DNA damage repair is a
process of the cell cycle, that
consist in to correct the mistakes
of genoma, happen during DNA
replication or caused by exogen
agents.
The aim of this process is to avoid
or to reduce the genetics mutation.
Some mechanims for DNA repair
are the elimination of mutagenics,
the nucleotids excision repair
(NER), the bases excision repair
(BER) and incorrect nucleotide
pairing repair.
Activation of DNA damage
repair pathways by murine
polyomavirus
Murine polyomavirus is a dsDNA virus that
causes serious respiratory, renal and brain
diseases. It must replicate in the nucleus
because some of the proteins that allow
DNA damage repair are necessary for its
development during the viral replication as
a consequence Murine polyomavirus use to
activate DNA damage repair pathways.
Ataxia-telangiectasia and Rad3 related
(ATR) and double strand break repair (MRE
11) are the principal proteins activated by
polyomavirus in order to optimize replicating
viral DNA.
My point of view
I consider that this investigation
is essential for to know
other options of treatment
in the viral infections, based
in the regulation or control
of members of DNA Damage
Repair pathways.

4. INTRODUCTION INTRODUCTION
The DNA damage repair is a
process of the cell cycle, that consist
in to correct the mistakes of
genoma, happen during DNA
replication or caused by exogen
agents.
The aim of this process is to avoid or
to reduce the genetics mutation.
Some mechanims for DNA repair
are the elimination of mutagenics,
the nucleotids excision repair (NER),
the bases excision repair (BER) and
incorrect nucleotide pairing repair.
DNA repair mechanisms are indispensable for
cell maintenance, no matter how emerged the
mutations, as a result of incorrect base pairs,
radiation exposure or caused by chemical
agents.
The most common DNA repair
mechanisms in humans are BER
and NER

5. Activation of DNA damage repair pathways by
murine polyomavirus
 Authors: Katie Heiser, Catherine
Nicholas, Robert L. Garcea
 26th July, 2016.
 This investigation tried to identify
the proteins of DNA repair
mechanisms necessary for viral
replication.
Activation of DNA damage
repair pathways by murine
polyomavirus
Murine polyomavirus is a dsDNA virus that
causes serious respiratory, renal and brain
diseases. It must replicate in the nucleus
because some of the proteins that allow
DNA damage repair are necessary for its
development during the viral replication as
a consequence Murine polyomavirus use to
activate DNA damage repair pathways.
Ataxia-telangiectasia and Rad3 related
protein (ATR) and double strand break
repair protein (MRE 11) are the principal
proteins activated by polyomavirus in order
to optimize replicating viral DNA.
My perspective
I consider that this investigation
is essential for to know
other options of treatment
in the viral infections, based
in the regulation or control
of members of DNA Damage Repair
pathways.

6. Activation of DNA damage repair
pathways by murine polyomavirus
 DNA damage repair proteins
can to promote the viral
replication, though also it has
the capacity to inhibit the viral
development .

7. Activation of DNA damage repair
pathways by murine polyomavirus
Ataxia telangiectasia and Rad3-related
protein (ATR) is an enzime responsible to
detect mistakes in DNA and activating
checkpoints, in order to correct it.
Ataxia telangiectasia and Rad3-related
protein (ATR) is an enzime responsible to
detect mistakes in DNA and activating
checkpoints, in order to correct it.
Double-strand break repair protein
(Mre11) is a protein with exonuclease
and
endonuclease activity, that take part
in homologous recombination.

8. Activation of DNA damage repair
pathways by murine polyomavirus
 During infection Murine
polyomavirus uses MRE11
and ATR in order to stabilizes
its replication, due to this the
decrease of proteins means a
lowest viral production.

9. Activation of DNA damage repair pathways by
murine polyomavirus
Student’s observation
I consider that this study is really important in the search of
new forms of treatment for the infections caused by
polyomavirus and others opportunistic viruses and is
certainly very interesting that a same pathways can to
avoid or promete the viral replication.

10. Influence of functional polymorphisms in DNA
repair genes of myelodysplastic syndrome
 Cancer Cytogenomic Laboratory, Center for
Research and Drug Development (NPDM),
Federal University of Ceara
 22nd July, 2016.
 This study tried to identify polymorphism
associated to myelodysplastic diseases in
relation with a defective DNA mismatch
repair system.
Influence of functional
polymorphisms in DNA repair
genes of myelodysplastic
syndrome
The myelodysplastic syndrome is a group
of diseases characterized by multiple
cytopenias, as a consequence of an altered
stem cell in the marrow bone.
Researchers at Federal University of
Ceara, discovered several polymorphisms
associated with the deficient of DNA repair
Mechanisms that cause this pathology.
My point of view
the relation between polymorphisms of
specific genes and the
myelodysplastic syndrome,
represents a new scientific
field for its diagnosis and
treatment. For this reason
the study of the implicated
genes in these diseases, is
a significant opportunity
for a future genetic therapy.

11. Influence of functional polymorphisms in DNA
repair genes of myelodysplastic syndrome
Myelodysplastic diseases
is the result of the
proliferation of mutated
stem cells.
Some genetic
polymorphisms affect the
capacity of repair DNA.

12. Influence of functional polymorphisms in DNA
repair genes of myelodysplastic syndrome
The polymorphism of genes that are
responsible of Homologous
recombination (BRCA1, BRCA2 and
RAD51) and non-homologous
recombination ( XRCC5, XRCC6 and
LIG4) are associated with
myelodisplasic diseases.

13. Influence of functional polymorphisms in DNA
repair genes of myelodysplastic syndrome
 Furthermore the upregulation of
several genes such as XRCC6
and LIG4, is a considerable
characteristic of damages in
DNA.

14. Influence of functional polymorphisms in DNA repair genes
of myelodysplastic syndrome
Student’s observation
 I consider that this investigation is determinant to find effective
myelodysplastic syndrome markers, that allow a early treatment,
in this way the incidence of this terrible pathology could to
decrease.

15. MEDICAL UTILITY
 If a cell does not recognize genetic
disorders, won't activate the
checkpoints and the damage will
pass to daughter cells.
 For this reason the investigation in
repair mechanisms is very
important in the search of new
treatments.
MEDICAL UTILITY
Many pathologies are
associated with deficient repair
mechanisms , because this
condition can modify the normal
cell process.
The most common example is
cancer, in this disease, the cell
loses the capacity of recognize
and repair the damaged DNA
and continues with the cell
cycle, allowing a mutagenic
proliferation.
In order to predict and create an
effective treatment for these
conditions, the actual
investigations are focus on
innumerable topics about DNA
damaged repair.

16. MEDICAL UTILITY
 Also the study of DNA damage
repair, and the involved proteins,
allow to understand the action
mechanism of many viruses and
the form of stop it.

17. MEDICAL UTILITY
 The relation between pathogenic
process and the presence of
proteins involved in DNA repair,
could mean the development of
new ways for detection and
control of several diseases.

18. MEDICAL UTILITY
 For an adequate treatment is necessary to understand
that gene expression can to change from one person
to another, in this way the identified polymorphisms
represents an important tool for the gene therapy.

19. BIBLIOGRAPHY
 MARTINEZ SÁNCHEZ, Lina María. Biología molecular. 8. ed.
Medellín: UPB. Fac. de Medicina, 2015. 109-115 p.
 Federal University of Ceara. (2016, July 22). Influence of
functional polymorphisms in DNA repair genes of
myelodysplastic syndrome. Leukemia Research. Retrieved
August 28, 2016 from http://
www.sciencedirect.com.consultaremota.upb.edu.co/science/a
rticle/pii/S0145212616301400
 Developmental Biology and BioFrontiers Institute; University
of Colorado. (2016, July 26). Activation of DNA damage repair
pathways by murine polyomavirus. Virology. Retrieved August
28, 2016 from http://
www.sciencedirect.com.consultaremota.upb.edu.co/science/a
rticle/pii/S0042682216302021