“So far there’s really no evidence that probiotics
affect emotions in humans.” — EMERAN MAYER
Belly bacteria can boss the brain
NEWS BRIEFS
By Tina Hesman Saey
Virus gene turns gypsy moth
caterpillars into climbers
Scientists have discovered a gene
that baculoviruses use to hijack
gypsy moth caterpillars’ brains.
When infected with the virus, the
caterpillars become climbers, scal-
ing the tree on which they live. At
the top, the caterpillars die, liquefy
and rain down viruses on other
gypsy moths. Now researchers
at Pennsylvania State University
in University Park and colleagues
have discovered that a baculovirus
gene called egt makes the cater-
pillars seek the heights. Viruses
lacking the gene still kill, but the
caterpillars stay down at the base
of the tree, the researchers report
in the Sept. 9 Science. The egt
gene produces an enzyme that
inactivates one of the caterpillar’s
molting hormones and leads to
climbing. — Tina Hesman Saey
Corticosterone
(nanograms/milliliter)
Bacteria ease stress Mice forced to
swim in a tank get stressed, but a diet that
includes a bacterium called Lactobacillus
rhamnosus lowers levels of a stress hormone.
Stress hormone levels
300
Comparison mice
under stress
200
Bacteria-fed mice
under stress
Endangered stem cells
Reprogrammed stem cells from
two of the world’s most endan-
gered species may help bring them
back from the brink of extinction.
Using frozen adult skin cells from
an endangered primate called a
drill and from a northern white
rhinoceros, scientists coaxed
the cells into an embryonic stem
cell–like state. The stem cells may
one day be used to create eggs
and sperm for breeding programs.
It took many failures before the
researchers succeeded in making
the cells from a male drill named
Loon and a female rhino named
Fatu, the researchers from UC San
Diego, the Scripps Research Insti-
tute and the San Diego Zoo report
online September 4 in Nature
Methods. — Tina Hesman Saey
www.sciencenews.org
October 8, 2011 | SCIENCE NEWS | 9
