Abstract
Changes in circadian rhythms of behavior are related to age-based division of labor in honey bee colonies. The expression of the clock gene period (per) in the bee brain is associated with age-related changes in circadian rhythms of behavior, but previous efforts to firmly associate per brain expression with division of labor or age have produced variable results. We explored whether this variability was due to differences in light and flight experience, which vary with division of labor, or differences in colony environment, which are known to affect honey bee behavioral development. Our results support the hypothesis that per mRNA expression in the bee brain is developmentally regulated. One-day-old bees had the lowest levels of expression and rarely showed evidence of diurnal fluctuation, while foragers and forager-age bees (>21 days of age) always had high levels of brain per and strong and consistent diurnal patterns. Results from laboratory and field experiments do not support the hypothesis that light, flight experience, and colony type influence per expression. Our results suggest that the rate of developmental elevation in per expression is influenced by factors other than the ones studied in our experiments, and that young bees are more sensitive to these factors than foragers.
Original language | English |
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Pages (from-to) | 879-891 |
Number of pages | 13 |
Journal | Insect Biochemistry and Molecular Biology |
Volume | 34 |
Issue number | 9 |
DOIs | |
State | Published - Sep 2004 |
Bibliographical note
Funding Information:We thank Allan Ross for expert assistance with the bees, Xiao-Lu Jin and Sara O’Brien for technical assistance in the laboratory, Bryan A. White for gracious permission to use the ABI 5700 real-time PCR machine, and Dionysios A. Antonopoulos and the rest of White’s laboratory group for friendly hospitality. Thanks to Amy Toth and Yair Shemesh and two anonymous reviewers for reviews of earlier versions of this manuscript. Financial support was provided by undergraduate fellowships from the University of Illinois (Howard Hughes and Environmental Council) and Colgate-Palmolive Corporation to CDR, NIH grant GM57196 to GER, and the Israel–US Binational Science Foundation grant 2001022 to GB and GER.
Keywords
- Biological clock
- Brain
- Circadian rhythms
- Clock gene
- Honey bee
- Social insects