|Expression of foraging gene associated with changes in bee behavior|
By Kate Dalke
May 9, 2002
The female honeybeethe worker in the hivelives a short, but busy life. She performs a variety of jobs, progressing from feeding royal jelly to eggs in the hive to collecting flower nectar and pollen outside. The age-related transition from nursing to foraging is associated with increased expression of the foraging gene, according to a new study.
"We propose that evolutionary changes in food-related behaviors, including complex social foraging, are based in part on changes in regulation of for [foraging gene] and other related genes," the researchers write in Science.
The researchers are still unsure of what actually stimulates the increased expression of the foraging gene. Foraging occurs because of a complex process of maturation that scientists hypothesize is related to social aspects, hormone levels, and environment.
Bees must be flexible in their maturation and development, according to Gene E. Robinson, who led the study at the University of Illinois at Urbana-Champaign in Illinois.
The foraging gene is one of the few genes implicated in the organization of an animal society, the researchers conclude.
In previous studies, scientists had identified the foraging gene in fruit flies and linked its expression to changes in behavior. Researchers discovered the same gene in the honeybee, Apis mellifera. They then compared expression of the foraging genewhich encodes for protein kinasein nurse bees and forager bees. Foragers demonstrated higher protein kinase activity and thus increased expression of the foraging gene, according to the study.
In a related study, also led by Robinson, researchers developed DNA microarrays to study gene expression in honeybees. They generated over 20,000 partial gene sequences representing almost 9,000 genes for studying gene expression in the bee brain. After testing the microarrays, they used comparative studies between the bee and other organisms to identify over 126 genes that are still found in the bee, but no longer present in the fruit fly.
"The honey bee is a highly social animal living in a complex society," says Robinson, "and this makes it an important organism to sequence."
Robinson says he hopes the first genomic project will propel the honeybee genome towards sequencing by the National Human Genome Research Institute. The institute, which sequenced the human genome last year and also announced a draft sequence of the mouse genome this week, has accepted proposals to determine which organism it will sequence next. Robinson submitted a proposal nominating the honeybee genome last February.
. . .