title: Notch signalling mediates reproductive constraint in the adult worker honeybee.
abstract: The hallmark of eusociality is the reproductive division of labour, in which one female caste reproduces, while reproduction is constrained in the subordinate caste. In adult worker honeybees (Apis mellifera) reproductive constraint is conditional: in the absence of the queen and brood, adult worker honeybees activate their ovaries and lay haploid male eggs. Here, we demonstrate that chemical inhibition of Notch signalling can overcome the repressive effect of queen pheromone and promote ovary activity in adult worker honeybees. We show that Notch signalling acts on the earliest stages of oogenesis and that the removal of the queen corresponds with a loss of Notch protein in the germarium. We conclude that the ancient and pleiotropic Notch signalling pathway has been co-opted into constraining reproduction in worker honeybees and we provide the first molecular mechanism directly linking ovary activity in adult worker bees with the presence of the queen.
authors.affiliation: Department of Biochemistry, Laboratory for Evolution and Development, Genetics Otago and Gravida (The National Centre for Growth and Development), University of Otago, P.O. Box 56, Dunedin 9054, Aotearoa-New Zealand.
authors.forename: Elizabeth J
authors.initials: EJ
authors.lastname: Duncan
authors.affiliation: Department of Biochemistry, Laboratory for Evolution and Development, Genetics Otago and Gravida (The National Centre for Growth and Development), University of Otago, P.O. Box 56, Dunedin 9054, Aotearoa-New Zealand.
authors.forename: Otto
authors.initials: O
authors.lastname: Hyink
authors.affiliation: Department of Biochemistry, Laboratory for Evolution and Development, Genetics Otago and Gravida (The National Centre for Growth and Development), University of Otago, P.O. Box 56, Dunedin 9054, Aotearoa-New Zealand.
authors.forename: Peter K
authors.initials: PK
authors.lastname: Dearden
mesh_terms: D000375:Aging / Q000378:metabolism*; D000818:Animals; D001516:Bees / Q000187:drug effects / Q000235:genetics / Q000378:metabolism*; D005260:Female; D005786:Gene Expression Regulation / Q000187:drug effects; D006608:Hierarchy, Social; D019476:Insect Proteins / Q000378:metabolism*; D008024:Ligands; D010053:Ovary / Q000187:drug effects / Q000378:metabolism; D010675:Pheromones / Q000494:pharmacology; D051880:Receptors, Notch / Q000378:metabolism*; D012098:Reproduction / Q000187:drug effects / Q000235:genetics; D015398:Signal Transduction / Q000187:drug effects
chemical_list: D019476:Insect Proteins; D008024:Ligands; D010675:Pheromones; D051880:Receptors, Notch