Expression Characterization and Localization of the foraging Gene in the Chinese Bee, Apis cerana cerana (Hymenoptera: Apidae)

In social insects, the foraging gene (for) regulates insect age- and task-based foraging behaviors. We studied the expression and localization of the for gene (Acfor) in Apis cerana cerana workers to explore whether the differential regulation of this gene is associated with the behaviors of nurses and foragers. The expression profiles of Acfor in different tissues and at different ages were examined using real-time quantitative reverse transcription polymerase chain reaction. Cellular localization in the brain was detected using in situ hybridization. Acfor transcripts in different ages workers showed that Acfor expression was detected in all the heads of 1- to 30-d-old worker bees. Acfor expression reached a peak at 25 d of age, and then declined with increasing age. The results showed that Acfor gene expression in five tissues was respectively significantly higher in foragers than in nurses. In nurses, the relative expression of Acfor was the highest in the antennae. There was a highly significant difference in expression between antennae, legs, and the other three tissues. In foragers, Acfor expression was the highest in the thorax, which was significantly different from all other tissues. In situ hybridization showed that Acfor was highly expressed in the lamina of the optic lobes, in a central column of Kenyon cells in the mushroom bodies of the brain of workers, and in the antennal lobes. This suggested that Acfor expression affects age-related foraging behavior in Apis cerana cerana, and that it may be related to flight activity.