Abstract
Caste-specific pheromone biosynthesis is a prerequisite for reproductive skew in the honeybee. Nonetheless, this process is not hardwired but plastic, in that egg-laying workers produce a queen-like pheromone. Studies with Dufour’s gland pheromone 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 esters). However, when incubated in vitro, the gland spontaneously exhibits the queen-like pattern, irrespective of its original worker type, prompting the notion that ester 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 pheromone 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.
References
Dombroski TCD, Simoes ZLP, Bitondi MMG (2003) Dietary dopamine causes ovary activation in queenless Apis mellifera workers. Apidologie 34:281–289
Dor R, Katzav-Gozansky T, Hefetz A (2005) Dufour’s gland pheromone as a reliable fertility signal among honeybee (Apis mellifera) workers. Behav Ecol Sociobiol 58:270–276
Harris JW, Woodring J (1995) Elevated brain dopamine levels associated with ovary development in queenless worker honey bees (Apis mellifera L). Comp Biochem Physiol 111:271–279
Hoover SER, Keeling CI, Winston ML, Slessor KN (2003) The effect of queen pheromones on worker honey bee ovary development. Naturwissenschaften 90:477–480
Jurenka RA (2004) Insect pheromone biosynthesis. Top Curr Chem 239:97–131
Katzav-Gozansky T, Soroker V, Hefetz A, Cojocaru M, Erdmann DH, Francke W (1997) Plasticity of caste-specific Dufour’s gland secretion in the honey bee (Apis mellifera L.). Naturwissenschaften 84:238–241
Katzav-Gozansky T, Soroker V, Hefetz A (2000) Plasticity in caste-related exocrine secretion biosynthesis in the honeybee (Apis mellifera). J Insect Physiol 46:993–998
Katzav-Gozansky T, Boulay R, Soroker V, Hefetz A (2004) Queen signal modulation of worker pheromonal composition in honeybees. Proc R Soc London B 271:2065–2069
Katzav-Gozansky T, Boulay R, Soroker V, Hefetz A (2006) Queen pheromones affecting the production of queen-like secretion in workers. J Comp Physiol A 192:737–742
Keller L, Nonacs P (1993) The role of queen pheromones in social insects: queen control or queen signal? Anim Behav 45:787–794
Makert GR, Paxton RJ, Hartfelder K (2006) Ovariole number—a predictor of differential reproductive success among worker subfamilies in queenless honeybee (Apis mellifera L.) colonies. Behav Ecol Sociobiol 60:815–825
Sasaki K, Nagao T (2001) Distribution and levels of dopamine and its metabolites in brains of reproductive workers in honeybees. J Insect Physiol 47:1205–1216
Tillman JA, Seybold SJ, Jurenka RA, Blomquist GJ (1999) Insect pheromones—an overview of biosynthesis and endocrine regulation. Insect Biochem Mol Biol 29:481–514
Visscher PK (1989) A quantitative study of worker reproduction in honey bee colonies. Behav Ecol Sociobiol 25:247–254
Visscher PK, Dukas R (1995) Honey bees recognize development of nestmates’ ovaries. Anim Behav 49:542–544
Weiss SA, Smith GC, Kalter SS, Vaughn JL (1981) Improved method for the production of insect cell-cultures in large volume. In Vitro 17:495–502
Acknowledgments
This research was supported by the Israel Science Foundation founded by the Israel Academy of Sciences and Humanities grant no. 720/04 to Abraham Hefetz. We thank Tovit Simon and Sharon Lefler for their technical help and Naomi Paz for the editorial assistance. This manuscript is contribution no. 507/06 from the Volcani Center, Israel. The experiments comply with the current laws of Israel.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Katzav-Gozansky, T., Hefetz, A. & Soroker, V. Brain modulation of Dufour’s gland ester biosynthesis in vitro in the honeybee (Apis mellifera). Naturwissenschaften 94, 407–411 (2007). https://doi.org/10.1007/s00114-006-0206-y
Received:
Revised:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00114-006-0206-y