Gene plays key evolutionary role in food-gathering behaviors

April 25, 2002

CHAMPAIGN, Ill. -- A new discovery in the brain of honeybees has researchers at three institutions suggesting that the gene they studied has played a key evolutionary role in the changes of food-gathering behaviors in many creatures.

When honeybees (Apis mellifera) grow up and leave the hive to begin foraging, their transition is helped along by an increase in the activity of the foraging gene (for). It stimulates an activity-boosting enzyme in some of the brain's visual processing centers, the researchers report in the April 26 issue of Science. Precocious foragers - bees stimulated to forage early - also have significantly higher brain levels of the gene's messenger RNA and four-fold higher levels of the enzyme, a cyclic GMP-dependent protein kinase called PKG.

Two forms of for previously had been found to influence naturally occurring variation in foraging behavior in Drosophila. "Rover" flies that cover large areas have high levels of PKG, while "sitter" flies that gather food nearby have low levels. PKG also has been linked to feeding arousal in some other invertebrates and vertebrates.

Honeybees live in a social world known for its distinct age-related division of labor. They begin their adult life working inside the hive as sanitation workers and nursemaids, among other roles. Foraging begins at two to three weeks of age, or whenever the needs of a colony require it. Nurse bees "loosely resemble sitter flies because they obtain food only in the more restricted confines of the beehive, while forager bees display rover-like behavior by ranging widely throughout the environment," the researchers wrote.

"The fact that at the molecular level there is a loose analogy between sitter flies and nurse bees on one hand and rover flies and foragers on the other hand is interesting for two reasons," said Gene Robinson, a professor of entomology and neuroscience at the University of Illinois.

First, it supports the idea that for may have had an evolutionary role in the changes of food-gathering behaviors in many creatures. Second, it demonstrates how the same gene in different species can be responsive to change over vastly different time scales - an evolutionary time scale in flies and a maturational or developmental one in bees," he said.

Before becoming foragers, honeybees make the transition from their role as nurses by going through a series of gradually widening orientation flights. During this time there are changes in brain chemistry and structure, endocrine activity and gene expression. Robinson and colleagues theorized that increased gene activity was necessary to drive behavioral change. Other genes had been implicated, but for is the first one shown to actually affect division of labor in honeybee colonies.

The researchers measured levels of the gene and its enzyme activity in precocious foragers to assure that the brain changes were not simply a natural result of age. Higher levels of gene expression and enzyme activity occurred in both in foragers making the transition in typical fashion (two to three weeks) and in those manipulated to forage at seven to nine days.

Additionally, the researchers used a pharmacological approach, feeding an experimental group of young bees with an analog that stimulated PKG activity. The treated bees started to forage precociously, while untreated bees did not.

The researchers believe that for and other genes that affect similar behaviors in different species might represent a class of genes that are particularly important to understanding the ways that genes influence behavior.
-end-
The authors of the paper are Robinson, Yehuda Ben-Shahar, a doctoral student in the UI entomology department; M.B. Sokolowski of the zoology department at the University of Toronto's Mississauga campus; and A. Robichon of the National Center for Scientific Research at the University of Bourgogne in France. The National Institutes of Health, Burroughs-Wellcome Trust and Canada Research Chair Program funded the research.

University of Illinois at Urbana-Champaign

Related Brain Articles from Brightsurf:

Glioblastoma nanomedicine crosses into brain in mice, eradicates recurring brain cancer
A new synthetic protein nanoparticle capable of slipping past the nearly impermeable blood-brain barrier in mice could deliver cancer-killing drugs directly to malignant brain tumors, new research from the University of Michigan shows.

Children with asymptomatic brain bleeds as newborns show normal brain development at age 2
A study by UNC researchers finds that neurodevelopmental scores and gray matter volumes at age two years did not differ between children who had MRI-confirmed asymptomatic subdural hemorrhages when they were neonates, compared to children with no history of subdural hemorrhage.

New model of human brain 'conversations' could inform research on brain disease, cognition
A team of Indiana University neuroscientists has built a new model of human brain networks that sheds light on how the brain functions.

Human brain size gene triggers bigger brain in monkeys
Dresden and Japanese researchers show that a human-specific gene causes a larger neocortex in the common marmoset, a non-human primate.

Unique insight into development of the human brain: Model of the early embryonic brain
Stem cell researchers from the University of Copenhagen have designed a model of an early embryonic brain.

An optical brain-to-brain interface supports information exchange for locomotion control
Chinese researchers established an optical BtBI that supports rapid information transmission for precise locomotion control, thus providing a proof-of-principle demonstration of fast BtBI for real-time behavioral control.

Transplanting human nerve cells into a mouse brain reveals how they wire into brain circuits
A team of researchers led by Pierre Vanderhaeghen and Vincent Bonin (VIB-KU Leuven, Université libre de Bruxelles and NERF) showed how human nerve cells can develop at their own pace, and form highly precise connections with the surrounding mouse brain cells.

Brain scans reveal how the human brain compensates when one hemisphere is removed
Researchers studying six adults who had one of their brain hemispheres removed during childhood to reduce epileptic seizures found that the remaining half of the brain formed unusually strong connections between different functional brain networks, which potentially help the body to function as if the brain were intact.

Alcohol byproduct contributes to brain chemistry changes in specific brain regions
Study of mouse models provides clear implications for new targets to treat alcohol use disorder and fetal alcohol syndrome.

Scientists predict the areas of the brain to stimulate transitions between different brain states
Using a computer model of the brain, Gustavo Deco, director of the Center for Brain and Cognition, and Josephine Cruzat, a member of his team, together with a group of international collaborators, have developed an innovative method published in Proceedings of the National Academy of Sciences on Sept.

Read More: Brain News and Brain Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.