Caste-specific @entity5681 biosynthesis is a prerequisite for reproductive skew in the @entity5157 . Nonetheless, this process is not hardwired but plastic, in that egg-laying workers produce a queen-like @entity5681 . Studies with Dufour's gland @entity5681 revealed that, in vivo, workers' gland biosynthesis matches the social status of the worker, i.e., sterile workers showed a worker-like pattern whereas fertile workers showed a queen-like pattern (production of the queen-specific @entity14743 ). However, when incubated in vitro, the gland spontaneously exhibits the queen-like pattern, irrespective of its original worker type, prompting the notion that @entity13507 production in workers is under inhibitory control that is queen-dependent. We tested this hypothesis by exposing queen or worker Dufour's glands in vitro to brain extracts of queens, queenright (sterile) workers and males. Unexpectedly, worker brain extracts activated the queen-like esters biosynthesis in workers' Dufour's gland. This stimulation was gender-specific; queen or worker brains demonstrated a stimulatory activity, but male brains did not. Queen gland could not be further stimulated. Bioassays with heated and filtered extracts indicate that the stimulatory brain factor is below 3,000 Da. We suggest that @entity5681 production in Dufour's gland is under dual, negative-positive control. Under queenright conditions, the inhibitor is released and blocks ester biosynthesis, whereas under queenless conditions, the activator is released, activating ester biosynthesis in the gland. This is consistent with the hypothesis that queenright workers are unequivocally recognized as non-fertile, whereas queenless workers try to become "false queens" as part of the reproductive competition.

Brain modulation of Dufour's gland ester biosynthesis in vitro in the @entity5157 ( XXXX ).

@entity5681 :: ('CHEBI:26013', 'Chemical') :: ['pheromone'] @entity13507 :: ('CHEBI:35701', 'Chemical') :: ['ester'] @entity5157 :: ('7460', 'Species') :: ['honeybee'] @entity14743 :: ('MESH:D004952', 'Chemical') :: ['esters']
@entity5157 :: (7460,Species) :: ['Apis mellifera']
