Plegable- Splicing
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Transcript of Plegable- Splicing
GRAND STUDENT HEARS CALLING TO SHARE SCIENCE WITH YOUTHS
AND ANTISENSE THERAPY FOR
SPINAL MUSCULAR ATROPHY SHOWS
PROMISEGLORIA STHEFANY TORRES
DAZAMEDICAL STUDENT
3° SEMESTER
INTRODUCTION
The splicing is a modification of an RNA after transcription, in which introns are removed and exons are joined.
The following news explains this important process, and gives a medical application.
GRAD STUDENT HEARS CALLING TO SHARE SCIENCE WITH YOUTHS
SCIENCE DAILY (AUGUST 13, 2010)
FIRST NEWS
Tuttle is a teacher in USA.
She spent 10 weeks that
summer studying the
dynamics of the hepatitis D
virus ribozyme, a virus that
promotes development of
the disease. More recently,
she has been working on a
project aimed at
determining which metal
atoms in the spliceosome
are responsible for driving
the chemistry of RNA
molecules.
“The splicesome is a critical piece of machinery in the cells,” Tuttle
explained. After DNA is transcribed into RNA, the spliceosome cuts that
RNA at precise positions and re-stitches it back together in a new way. The transcripts need to be precisely
spliced “because if you mess that up, you’re not going to be producing the
correct gene products. And sure enough, splicing defects have been implicated in a number of human
diseases.”
As an elementary school student, Tuttle thought science was all about
answering multiple-choice questions from a textbook, not working with the yeast colonies, RNA molecules
and X-ray films of her daily routine. A middle-school
chemistry class changed all that. Now she feels drawn toward both research and
science education.
“I really loved teaching. It was fantastic to bring science to the new generation,” she said. For now, “I just want to do good science here and see where it takes me.”
STUDENT OBSERVATION: 1° NEWS
The spliceosome is a topic very interesting for the scinece and the
students too. And the most important is the example thah Tuttle give us,
because, she teach us to study with dedication the topics about the
science and looking for the utility to the humanity.
ANTISENSE THERAPY FOR SPINAL MUSCULAR ATROPHY SHOWS PROMISE
SCIENCE DAILY (JULY 12, 2010)
SECOND NEWS
Scientists at Cold Spring
Harbor Laboratory and
California-based Isis
Pharmaceuticals have
succeeded in reversing
symptoms of Type III SMA, a
relatively mild form of the
disease, in mice by introducing
an ASO into their spinal cords.
The ASO fixes the molecular
mistake underlying SMA by
redirecting a cellular editing
process called alternative
splicing.
SMA is caused by insufficient le
vels of a
protein called Survival of Motor N
euron
(SMN) in th
e spinal cord's m
otor neurons,
which waste away along with th
e muscles
that they can no longer contro
l. The SMN1
gene, which produces th
e SMN protein, is
missing or m
utated beyond repair in
SMA
patients. Humans h
ave a second SMN-
producing gene called SMN2, but this g
ene
is a poor b
ackup, as it produces v
ery little
functional SMN protein. This deficiency
stems fr
om a mistake th
at occurs durin
g
splicing, a molecular editin
g process that
kicks in afte
r the gene's D
NA has been
copied into RNA.
This treatment prevented both tail and ear necrosis in the neonates and embryos, which developed into adults with normal tails and ears. The researchers suggest
that supplying the therapeutic ASO to the
animals' central nervous system, which restored
cellular SMN protein levels, might in turn prevent
neuronal deterioration, muscle wasting, and
vascular problems in the tail and ears.
The collaborators have now overcome this limitation by directly delivering ASOs into the animals' central nervous system, a common route of administration for other drugs such as chemotherapy agents. Infusing ASOs into the fluid
that surrounds the brain and spinal cord resulted in a robust increase in the levels of SMN protein in individual motor neurons throughout the spinal cord of type III SMA
mice.
In 2008, the team injected
these ASO molecules into the
bloodstream of mice
engineered to carry a human
SMN2 gene that display
symptoms of type III SMA. This
regimen corrected SMN2
splicing in the animals' liver
and kidneys but not in spinal
cord neurons -- where they are
most needed -- because the
ASOs failed to breach the
blood-brain barrier and enter
the spinal cord.
STUDENT OBSERVATION 2° NEWS
In this news the sciencetists team shows the way to save the patient with SMA,
through the alternative splicing. It is a very important investigation, because the
molecular biology is the basic of many process with medical utility, besides this
procces helps to the medical advances and the global health too.
MEDICAL UTILITY
Investigations about splicing
procces
Aplication of alternative
splicing
Best live quality to the people
A mistake that occurs during splicing can be produced different
diseases in the people.
Using alternative splicing reporters the sciencetist and
doctors have previously observed mesenchymal epithelial
transitions in rat prostate tumors.
The splicing can contribute to the etiology of cancer and serve as a marker to establish the diagnosis
of cancer
The human genome sequencing project suggests approximately 20,000-25,000 genes. Among these, about 35-60% of genes generate multiple mRNAs by
alternative splicing mechanism and contribute to the diversity of the proteomic world. This ‘gene
shortfall’ has ignited considerable interest in alternative RNA splicing
Tow major goal of regenerative medice are the transformation of adult somatics cells and to control
their differentiation, Tihs goal wold be helped by obtaining a
RNA isoforms , during the alternative splicing.
I THINK THAT THE SPLICING IS A VERY IMPORTANT PROCESS IN THE MOLECULAR BIOLOGY AND MEDICAL INVESTIGATIONS
BECAUSE IT IS THE FUNDAMENTAL BASE TO CURE STRANGERS DISEASES AND IT GIVES DIFFERENT
POSSIBILITIES OF ITS TREATMENT AND DIAGNOSTIC.
BIBLIOGRAPHY Grand Student Hears Calling Share Science with Younts.
The University of Chicago News Office.
URL: http://www.newswise.com/articles/grad-student-hears-calling-to-share-science-with-youths
Antisense Therapy for Spinal Muscular Antrophy Shows Promise. Science Daily. URL: http://www.sciencedaily.com/releases/2010/07/100712103501.htm
MARTINES, S. Lina María. Biología Molecular. Quinta edición. Medellín 2009. P 142, 195.
REVIEW ARTICLE. URL: http://www.bioline.org.br/pdf?hg06009
SPRINGERLINK. URL: http://www.springerlink.com/content/551x720542804742/