The Raelian Movement
for those who are not afraid of the future : http://www.rael.org
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Mechanism for Changing Adult Cells Into Stem-Like Cells Discovered
http://www.sciencedaily.com/releases/2010/10/101007123111.htm
ScienceDaily (Oct. 7, 2010) — In 2006, Dr. Shimya Yaminaka of Kyoto
University in Japan set the stem cell and regenerative medicine
research world on fire when he successfully transformed differentiated
mouse skin cells into cells that looked and behave like embryonic stem
cells. Embryonic stem cells, the subject of much controversy when used
in research, have the ability to differentiate into any type of
tissue.
Yaminaka's creation of induced pluripotent stem cells [iPSCs] meant
that in the future, research to improve human disease might be able to
use iPSCs in lieu of embryonic stem cells. Since then, researchers
around the world have been able to replicate his process. However, no
one has been able to unlock the mechanism that allows cells to be
regressed from differentiated to undifferentiated cells -- until now.
University of Colorado Cancer Center researcher Chuan-Yuan Li, PhD,
and his group have discovered that so-called "grim-reaper" caspase
genes are the gatekeepers that can open the door to allow
differentiated adult cells to regress to undifferentiated iPSCs.
"By doing experiments in which we added caspase inhibitor genes to the
Yaminaka protocol, we discovered that when caspases are turned off,
you cannot make IPSCs," says Li, professor of radiation oncology at
the University of Colorado School of Medicine. "We were able to shut
down the process almost completely."
The discovery is the cover article in the Oct. 8, 2010 issue of Cell Stem Cell.
"For practical reasons, the discovery is important because even though
the transformation to iPSCs is a straightforward process on surface,
it is not very efficient, and this information can help increase
efficiency," Li says. "It can also help with the problem of cells that
don't complete the transformation process acting like cancer cells.
And from a purely scientific perspective, it is fascinating to
understand why the magic happens."
Li's group had been working on the roles of caspases in wound healing
when Yaminaka published his initial iPSC work in mice. That got Li
thinking about potential roles of caspases in iPSC generation.
"I thought maybe caspases could also induce iPS cells instead of the
four transcriptional factors that Yamanaka used," he says. "If that
was true, it would be very exciting."
For six months, his group tried different experiments using various
caspase genes to coax human skin cells into iPS cells, but they had no
success. Although caspases were not sufficient to make iPS cells, Li
kept going with the idea that caspases were somehow involved.
They made their discovery when they introduced the caspase inhibitors
into skin cells, which almost completely shut down the induction of
iPS cells.
Caspases, Li says, appear to loosen up the built-in controls that make
a cell differentiated or undifferentiated, just like a clutch allows a
driver to switch gears while driving. Undifferentiated stem-like cells
and differentiated cells from one person have the exact same genes.
The difference between them is which genes are turned on or off.
In other words, he says, caspases could be the key to a kind of
cellular reincarnation -- taking a cell that, during human
development, became a skin cell back to its original state to become
any kind of cell.
"About twenty years ago, a scientist who was among the first to clone
the caspase 3 gene named the gene Yama, the Hindu Lord of Death who
was responsible for both killing a being and setting him on his way
into his reincarnated life," Li said. "It is now becoming clear that
caspases don't just kill, but they can change the cell's fate. They
could be a mediator of epigenetic changes in multi-cellular
organisms."
Members of Li's research group who were integral to the studies
include Fang Li, the paper's lead author, Zhimin He, Jingping Shen,
Qian Huang, Wenrong Li, Xinjian Liu, Yujun He and Frank Wolf.
Editor's Note: This article is not intended to provide medical advice,
diagnosis or treatment.
Story Source:
The above story is reprinted (with editorial adaptations by
ScienceDaily staff) from materials provided by University of Colorado
Denver, via EurekAlert!, a service of AAAS.
Journal Reference:
1. Fang Li, Zhimin He, Jingping Shen, Qian Huang, Wenrong Li,
Xinjian Liu, Yujun He, Frank Wolf, Chuan-Yuan Li. Apoptotic Caspases
Regulate Induction of iPSCs from Human Fibroblasts. Cell Stem Cell,
Volume 7, Issue 4, 508-520, 8 October 2010 DOI:
10.1016/j.stem.2010.09.003
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"Ethics" is simply a last-gasp attempt by deist conservatives and
orthodox dogmatics to keep humanity in ignorance and obscurantism,
through the well tried fermentation of fear, the fear of science and
new technologies.
There is nothing glorious about what our ancestors call history,
it is simply a succession of mistakes, intolerances and violations.
On the contrary, let us embrace Science and the new technologies
unfettered, for it is these which will liberate mankind from the
myth of god, and free us from our age old fears, from disease,
death and the sweat of labour.
Rael
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