The genome of the mountain pine
beetle1 -- the insect that has
devastated2 B.C.'s
lodgepole pine(美国黑松) forests -- has been
decoded3 by researchers at the University of British Columbia and Canada's Michael Smith Genome Sciences Centre. This is a first for the mountain pine beetle and only the second beetle genome ever sequenced. The first was the red flour beetle, a pest of stored grains. The genome is described in a study published Tuesday in the journal Genome Biology.
"We know a lot about what the
beetles4 do," says Christopher Keeling, a research associate in Prof. Joerg Bohlmann's lab at the Michael Smith Laboratories. "But without the genome, we don't know exactly how they do it."
"Sequencing the mountain pine beetle genome provides new information that can be used to help manage the
epidemic5 in the future."
The genome revealed large variation among individuals of the species -- about four times greater than the variation among humans.
"As the beetles' range expands and as they head into
jack6 pine forests where the
defensive7 compounds may be different, this variation could allow them to be more successful in new environments," says Keeling.
Researchers
isolated8 genes10 that help detoxify defence compounds found under the bark of the tree -- where the beetles live. They also found genes that degrade plant cell walls, which allow the beetles to get
nutrients11 from the tree.
Keeling, Bohlmann and their colleagues also uncovered a
bacterial12 gene9 that has jumped into the mountain pine beetle genome. This gene codes for an
enzyme13 that digests sugars.
"It might be used to digest woody tissue and/or the microorganisms that grow in the beetle's tunnels
underneath14 the bark of the tree," said Keeling. "Gene transfers sometimes make organisms more successful in their environments."
This study involved researchers from the University of Northern British Columbia and the University of Alberta.