Science

PLANT SCIENCES

Never too late

Flowers are more resilient
than they appear. They
shoot up against all odds.
The credit goes to genetic
matter called microRNA that
inhibit protein formation
crucial to flowering in
young plants. External
cues like sunlight
make them
flower. But in
the absence of cues,
too, flowers do blossom;
the activity of microRNA
decreases with age ensuring
enough flowering proteins
are produced before the
plant dies (Cell, August 21).

HEALTH SCIENCES

An anti-cancer bacterium

Salinispora tropica

Cancerous cells divide and grow
much faster than healthy cells. As
a consequence, cancer cells accumulate
larger quantities of waste.
The waste is managed by protein
molecules called proteasomes which
are a cell's sanitation workers. In their
absence a cell will choke on its waste and die. Cancer
researchers have found a molecule produced by a marine
bacterium (Salinispora tropica) that can choke the cancer
cells by disabling their proteasomes. Drugs manufactured to
target cancerous cells end up hurting healthy cells as well. In
this case, the healthy cells were found to better resist the
drug thus restricting its impact mostly on the cancerous ones
(Journal of Medicinal Chemistry, August).

MARINE ECOLOGY

Its a tough one

Plastic does not decompose.
It stays intact in a landfill for
hundreds of years. This
makes it difficult to get rid
of one of the most toxic pollutants
ever created by man.
A team found it does
decompose in
oceans, and with
surprising rapidity.
But this is not
good news. The
team simulated
the temperatures and
other conditions that leads
to plastic's breakdown in the
ocean and found that it adds
two very toxic compounds
to the water, namely,
bisphenol and styrene.
These are not found naturally
and while bisphenol disrupts
hormone functions,
styrene is a potent carcinogen.
Millions of
tonnes of plastic
debris enter the
oceans every year.
(American Chemical
Society meeting,
August)

ASTROPHYSICS

The sun has flares

The temperature of the sun's
surface is 5,427 C. Yet it is
millions of degrees cooler
than the sun's outer atmosphere.
Astrophycists probing
into the mystery found the
answer in sudden bursts of
energy called nanoflares.
These can also be blamed for
influencing changes in X-ray
and UV radiations which
enter the earth's atmosphere
and disrupt communication
signals like radio and electrical
transmissions
(International Astronomical
Union General Assembly,
August 6).

PHYSIOLOGY

The nod to kill

The immune system releases
a protein molecule when the
respiratory system is
attacked. This protein, called
NOD2, can recognize the
influenza A and the respiratory
tract infection virus.
Microbiologists say it is
more than a sensor: the
immune system cannot
attack the viruses unless
the protein orders it to do
so. In tests, mice lacking
the sensor died of respiratory
infections in 10 days.
This molecule can be used
to develop drugs to boost
the immune system. In people
with lowered immunity
such diseases are life-threatening
(Nature, August 23

LIFE SCIENCES

What makes her fat

Active levels of testosterone
in the blood of
menopausal women
causes visceral fat
to accumulate;
age is not the
culprit as was
believed. Earlier
studies have
shown that
increase in visceral
fat is a risk
factor for acute
coronary diseases
and
strokes. Female
reproductive
organs produce testosterone
in low quantities.
Although a male
hormone, it helps
women maintain muscle
and bone strength.
During the menopause
transition period
there is hormonal
imbalance leading to
an increase in the
blood level of
testosterone
(Obesity, August
20).

PARASITOLOGY Dinner at 7? Of the various tricks that parasites use to fool host immune systems, here is a new one: the parasite that causes leishmaniasis (kala azar), coaxes the immune system to feed it instead of killing it. When an infected sandfly bites a human it transfers the parasites along with a sticky gel produced by them. Immune cells are then released at the site. These cells usually produce nitric oxide to kill the pathogens. In this case, the researchers found they produced polyamines--food for the parasite. On further research, they found the sticky gel responsible in helping the parasite establish this connection with the immune cells. The same gel protects the parasites from the fly's defences. (PLoS Pathogens, August 20)