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DNA stores data in rewritable form
By Alexandra Witze
They aren’t yet competition for Intel,
but bioengineers have created a one-bit
“memory” made of DNA that can record,
erase and re write data within living cells.
One day, doctors might be able to
insert such devices into a cancer patient
to tally how many times a cell divides and
flag malignant growth. Or researchers
might track exactly what happens inside
cells as they age. The work is an advance
in synthetic biology, a field in which scientists create tools to control life’s basics
from the cell on up.
“We can write and erase DNA in a living
cell,” says bioengineer Jerome Bonnet of
Stanford University. “Now we can bring
logic and computation inside a cell itself.”
Bonnet and colleagues, led by Stanford’s Drew Endy, describe the feat
online May 21 in the Proceedings of the
National Academy of Sciences.
Scientists have long dreamed of put-
ting tiny computers inside the body to
monitor or even control what’s going
on. But nobody has made a silicon-based
computer chip small enough to embark
on a fantastic computing voyage inside
a cell.
10 genes for poppy potion
opium poppies, such as the Tasmanian flowers pictured here,
are prized for the valuable drugs they produce. Scientists have
long known how the plants make opiates such as codeine and
morphine, but the molecular steps the plants use to make a nonaddictive substance called noscapine have been a mystery until
now. Noscapine is a cough suppressant that is also used as an
antitumor drug. a group of 10 genes carries the instructions for
building the enzymes that Papaver somniferum plants use to produce noscapine, Ian Graham of the University of York in england
and colleagues report online May 31 in Science. Poppies with
two copies of each of the noscapine-producing genes make high
levels of the drug, while poppies that inherit only one copy of the
genes make less noscapine. Poppies that lack the genes make
none of the drug. The discovery could make it easier for drug
companies to manufacture noscapine. — Tina Hesman Saey
Carol Walker
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