Honey bees are long-standing research models of behavior.  With new advances in biotechnology and the genomic sciences, we can now develop honey bees as a model for examining the molecular mechanisms underlying behavior.  I have begun to study a gene called Kruppel homologue 1 (kr-h1), a zinc-finger transcription factor whose sequence is well-conserved among insects.  Kr-h1 mRNA levels are higher in forager honey bees than in young bees (Grozinger C.M. et al. 2003. PNAS 100:14519-14525).  Also, ten-day old virgin queen honey bees have higher kr-h1 expression than same-aged workers (unpublished data).  Honey bee queens and foragers share a common trait in that they leave the hive using flight.  The mushroom bodies of these groups increase in volume during this time as well (Fahrbach S.E. 2006. Annu. Rev. Entomol. 51:209-32).  The mushroom bodies have long been considered the centers of learning and memory integration of the insect brain and expansion in these regions may increase the honey bee’s ability to learn and remember landmarks and routes while foraging or taking mating flights.  Interestingly, kr-h1 expression is differentially regulated between young bees and foragers in the mushroom bodies of the brain (Grozinger C.M. et al. 2003. PNAS 100:14519-14525). Based on these experimental findings, we hypothesize that kr-h1 is involved in the mushroom body expansion that prepares bees for flight.  We will monitor the effect of flight on kr-h1 in honey bee brains by observing mRNA and protein levels in different honey bee castes.