by Jeffrey Norris
April 15, 2013
from
UCSF Website
UCSF researchers have
uncovered a role in brain development and in neurological
disease for little appreciated molecules called long noncoding RNA.
In this image,
fluorescent dyes track the presence of the RNA molecules and the
genes they
affect in the developing mouse brain.
Image courtesy of
Alexander Ramos
Specific DNA once dismissed as junk
plays an important role in brain development and might be involved
in several devastating neurological diseases, UC San Francisco
scientists have found.
Their discovery in mice is likely to
further fuel a recent scramble by researchers to identify roles for
long-neglected bits of DNA within the genomes of mice and humans
alike.
While researchers have been busy
exploring the roles of proteins encoded by the genes identified in
various genome projects, most DNA is not in genes. This so-called
junk DNA has largely been pushed aside and neglected in the wake of
genomic gene discoveries, the UCSF scientists said.
In their own research, the UCSF team
studies molecules called long noncoding RNA (lncRNA, often
pronounced as “link” RNA), which are made from DNA templates in the
same way as RNA from genes.
“The function of these mysterious
RNA molecules in the brain is only beginning to be discovered,”
said Daniel Lim,
MD, PhD, assistant professor of neurological surgery, a member
of the Eli and Edythe Broad Center of Regeneration Medicine and
Stem Cell Research at UCSF, and the senior author of the study (Integration
of Genome-wide Approaches Identifies lncRNAs of Adult Neural
Stem Cells and Their Progeny In Vivo),
published online April 11 in the journal
Cell Stem Cell.
Daniel Lim, MD, PhD
Alexander Ramos, a student enrolled in
the MD/PhD program at UCSF and first author of the study, conducted
extensive computational analysis to establish guilt by association,
linking lncRNAs (Long noncoding RNA) within cells to the activation of genes.
Ramos looked specifically at patterns
associated with particular developmental pathways or with the
progression of certain diseases. He found an association between a
set of 88
long noncoding RNAs and
Huntington’s disease, a deadly
neurodegenerative disorder.
He also found weaker associations
between specific groups of long noncoding RNAs and
Alzheimer’s
disease, convulsive seizures, major depressive disorder and various
cancers.
“Alex was the team member who
developed this new research direction, did most of the
experiments, and connected results to the lab’s ongoing work,”
Lim said.
The study was mostly funded through
Lim’s grant - a National Institutes of Health (NIH) Director’s New
Innovator Award, a competitive award for innovative projects that
have the potential for unusually high impact.
LncRNA
versus Messenger RNA
Unlike messenger
RNA, which is
transcribed from the DNA in genes and guides the production of
proteins, lncRNA molecules do not carry the blueprints for proteins.
Because of this fact, they were long
thought to not influence a cell’s fate or actions.
Alexander Ramos
Nonetheless, lncRNAs also are
transcribed from DNA in the same way as messenger RNA, and they,
too, consist of unique sequences of nucleic acid building blocks.
Evidence indicates that lncRNAs can
tether structural proteins to the DNA-containing chromosomes, and in
so doing indirectly affect gene activation and cellular physiology
without altering the genetic code. In other words, within the cell,
lncRNA molecules act “epigenetically” - beyond genes - not through
changes in DNA.
The brain cells that the scientists
focused on the most give rise to various cell types of the central
nervous system.
They are found in a region of the brain
called the subventricular zone, which directly overlies the
striatum. This is the part of the brain where neurons are destroyed
in Huntington’s disease, a condition triggered by a single genetic
defect.
Ramos combined several advanced
techniques for sequencing and analyzing DNA and RNA to identify
where certain chemical changes happen to the chromosomes, and to
identify lncRNAs on specific cell types found within the central
nervous system. The research revealed roughly 2,000 such molecules
that had not previously been described, out of about 9,000 thought
to exist in mammals ranging from mice to humans.
In fact, the researchers generated far
too much data to explore on their own.
The UCSF scientists created a website
through which their data can be used by others who want to study the
role of lncRNAs in development and disease.
“There’s enough here for several
labs to work on,” said Ramos, who has training grants from the
California Institute for Regenerative Medicine (CIRM) and the
NIH.
“It should be of interest to
scientists who study long noncoding RNA, the generation of new
nerve cells in the adult brain, neural stem cells and brain
development, and embryonic stem cells,” he said.
Other co-authors who worked on the study
include UCSF postdoctoral fellows,
Additional funders of the study included
the Sontag Foundation and the Sandler Foundation.
Junk DNA Crucial for Brain Development
by PTI
April 16, 2013
from
FreePressJournal Website
Washington
Specific DNA once dismissed as junk
plays an important role in brain development and may be involved in
several devastating neurological diseases, a new study has found.
The so-called junk DNA has largely been pushed aside and neglected
in the wake of genomic gene discoveries, said researchers from the
University of California, San Francisco.
The team studied molecules called long noncoding RNA (lncRNA, often
pronounced as ‘link’ RNA), which are made from DNA templates in the
same way as RNA from genes.
“The function of these mysterious
RNA molecules in the brain is only beginning to be discovered,”
said Daniel Lim, the senior author of the study published in the
journal Cell Stem Cell.
Alexander Ramos, a student at UCSF and
first author of the study, conducted extensive computational
analysis to establish guilt by association, linking lncRNAs within
cells to the activation of genes.
Ramos looked specifically at patterns associated with particular
developmental pathways or with the progression of certain diseases.
He found an association between a set of 88 long noncoding RNAs and
Huntington’s disease, a deadly neurodegenerative disorder.
He also found weaker associations between specific groups of long
noncoding RNAs and Alzheimer’s disease, convulsive seizures, major
depressive disorder and various cancers.
Ramos combined several advanced techniques for sequencing and
analyzing DNA and RNA to identify where certain chemical changes
happen to the chromosomes, and to identify lncRNAs on specific cell
types found within the central nervous system.
The research revealed roughly 2,000 such molecules that had not
previously been described, out of about 9,000 thought to exist in
mammals ranging from mice to humans.
In fact, the researchers generated far too much data to explore on
their own so they have created a website through which their data
can be used by others who want to study the role of lncRNAs in
development and disease.
Junk DNA May Be Behind Devastating
Neurological Diseases
April 16, 2013
from
ZeeNews Website
Washington
UC San Francisco scientists have
revealed that specific DNA once dismissed as junk plays an important
role in brain development and might be involved in several
devastating neurological diseases.
Their discovery in mice is likely to further fuel a recent scramble
by researchers to identify roles for long-neglected bits of DNA
within the genomes of mice and humans alike.
While researchers have been busy exploring the roles of proteins
encoded by the genes identified in various genome projects, most DNA
is not in genes. This so-called junk DNA has largely been pushed
aside and neglected in the wake of genomic gene discoveries, the
UCSF scientists said.
In their own research, the UCSF team studies molecules called long
noncoding RNA (lncRNA, often pronounced as "link" RNA), which are
made from DNA templates in the same way as RNA from genes.
"The function of these mysterious
RNA molecules in the brain is only beginning to be discovered,"
said Daniel Lim, MD, PhD, assistant professor of neurological
surgery, a member of the Eli and Edythe Broad Center of
Regeneration Medicine and Stem Cell Research at UCSF, and the
senior author of the study.
Alexander Ramos, a student
enrolled in the MD/PhD program at UCSF and first author of the
study, conducted extensive computational analysis to establish guilt
by association, linking lncRNAs within cells to the activation of
genes.
Ramos looked specifically at patterns associated with particular
developmental pathways or with the progression of certain diseases.
He found an association between a set of 88 long noncoding RNAs and
Huntington`s disease, a deadly neurodegenerative disorder.
He also found weaker associations
between specific groups of long noncoding RNAs and Alzheimer`s
disease, convulsive seizures, major depressive disorder and various
cancers.
Unlike messenger RNA, which is transcribed from the DNA in genes and
guides the production of proteins, lncRNA molecules do not carry the
blueprints for proteins. Because of this fact, they were long
thought to not influence a cell's fate or actions.
Nonetheless, lncRNAs also are transcribed from DNA in the same way
as messenger RNA, and they, too, consist of unique sequences of
nucleic acid building blocks.
Evidence indicates that lncRNAs can tether structural proteins to
the DNA-containing chromosomes, and in so doing indirectly affect
gene activation and cellular physiology without altering the genetic
code. In other words, within the cell, lncRNA molecules act
"epigenetically" - beyond genes - not through changes in DNA.
The brain cells that the scientists focused on the most give rise to
various cell types of the central nervous system.
They are found in
a region of the brain called the subventricular zone, which directly
overlies the striatum. This is the part of the brain where neurons
are destroyed in Huntington`s disease, a condition triggered by a
single genetic defect.
Ramos combined several advanced techniques for sequencing and
analyzing DNA and RNA to identify where certain chemical changes
happen to the chromosomes, and to identify lncRNAs on specific cell
types found within the central nervous system. The research revealed
roughly 2,000 such molecules that had not previously been described,
out of about 9,000 thought to exist in mammals ranging from mice to
humans.
In fact, the researchers generated far too much data to explore on
their own. The UCSF scientists created a website through which their
data can be used by others who want to study the role of lncRNAs in
development and disease.
The study was published online in the journal Cell Stem Cell.
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