2012-12-11 11:51:58
By Mark Kinver Environment reporter, BBC News
Researchers say they have unlocked the genetic secrets of honey bees' high
sensitivity to environmental change.
Scientists from the UK and Australia think their findings could help show links
between nutrition, environment and the insects' development.
It could, they suggest, offer an insight into problems like Colony Collapse
Disorder, a mysterious cause of mass bee deaths globally.
The findings appear in Insect Biochemistry and Molecular Biology.
"Honey bees live in complex societies comprising tens of thousands of
individuals," explained study co-author Paul Hurd from Queen Mary, University
of London.
"Most of these are female 'worker' honeybees that are unable to reproduce and
instead devote their short lives to finding food in flowers... and other tasks
such as nursing larvae inside the hive."
But the hive has a queen as well - the much longer-lived, reproductive head of
the hive,
"When the queen bee lays her eggs, worker bees can determine whether the
resulting larvae are to become an adult worker bee or an adult queen bee," Dr
Hurd said.
"The type of food the larvae is fed dictates the developmental outcome - larvae
destined to become workers are fed a pollen and nectar diet, and those destined
to become queens are fed royal jelly.
"This difference in feeding is maintained over the entire lifetime of the
worker or queen bee."
The change is suggested to be the result of a "histone code" - a process that
sees genetic changes made to proteins called histones within cells' nuclei.
Rather than "genetic" changes that are locked into DNA, these are known as
"epigenetic" changes.
The report marks the first time such effects had been recorded in honey bees.
"The development of different bees from the same DNA in the larvae is one of
the clearest examples of epigenetics in action - mechanisms that go beyond the
basic DNA sequence," said co-author Mark Dickman from the University of
Sheffield.
"From our knowledge of how the histone code works with in other organisms, we
think the marks on the histone proteins might act as one of the switches that
control how the larvae develop."