Stem cell populations reside in niches within organs that control when stem cells replicate or produce daughter cells. A study in fruit flies found that the division of stem cells in testes is regulated at the final stage of replication before daughter cells separate. Previous studies showed different stem cell types in the fruit fly testis niche had to coordinate to properly make sperm. Advances in understanding stem cell replication and DNA damage repair could enable greater progress in tissue regeneration and gene therapy.

1. REPLICATION
BY: LUIS FELIPE ÁLVAREZ HERNÁNDEZ

4. INTRODUCTION

5. Fruitfly sperm cells reveal intricate
coordination in stem cell replication

6. Stem cell populations reside
in areas called niches deep
within different types of
organs.
Scientists think that these
niches control stem cell
behavior, that is "telling" the
stem cell when to produce
more stem cells or when to
produce daughter cells
Fruitfly sperm cells reveal intricate
coordination in stem cell replication

7. DiNardo and Lenhart showed
that the division of these stem
cells is regulated at the final
stage of replication, called
cytokinesis, right before the
two daughter cells separate.
Fruitfly sperm cells reveal intricate
coordination in stem cell replication

8. Fruitfly sperm cells reveal intricate
coordination in stem cell replication
In the fruitfly testis niche, previous
studies have shown that different
stem cell types had to coordinate
with each other.
If their respective functions were
uncoupled from each other, by
mutation for example, the testis
could not make sperm.

9. PERSONAL COMMENT: I think the
investigation is on track, and that
these advancements can combat the
irregular gene expression and cell
division for medical purposes
Fruitfly sperm cells reveal intricate
coordination in stem cell replication

10. Forks colliding: How DNA breaks during
re-replication

11. Forks colliding: How DNA breaks during
re-replication
Improved analysis have
uncovered the genetic
alterations in amplification
and methods of redress

12. Forks colliding: How DNA breaks during
re-replication
DNA breaks are
mended in one of two
ways
: (NHEJ) is rapid but
prone to mistakes
(HR) takes longer but
is much more
accurate.

13. Forks colliding: How DNA breaks during
re-replication
Now they can begin to
isolate the individual
components involved in
the repair pathways,
resolve their precise roles

14. Forks colliding: How DNA breaks during
re-replication
PERSONAL COMMENT: this
kind of progress however
small are huge in molecular
biology and lets continue to
create benefits

15. MEDICAL
UTILITY

16. MEDICAL UTILITY
The discover where
DNA damage is
repaired , will enable
can find better gene
therapy

17. MEDICAL UTILITY
Proper use of stem cell
discoveries will provide
greatest advances in tissue
reconstruction

18. MEDICAL UTILITY
Will enable create the
"superman" to the bad
genetic odds, without
irreparable alteration

19. BIBLIOGRAPHY
• 1. University of Pennsylvania School of Medicine. "Fruitfly sperm
cells reveal intricate coordination in stem cell replication: Basic cell
biology study lends new view of early steps of tissue regeneration."
ScienceDaily. ScienceDaily, 15 July 2015.
www.sciencedaily.com/releases/2015/07/150715122354.htm.
• 2. Whitehead Institute for Biomedical Research. "Forks colliding:
How DNA breaks during re-replication." ScienceDaily. ScienceDaily,
4 June 2015.
www.sciencedaily.com/releases/2015/06/150604141527.htm.

20. “Development is just around the corner”