@article{ThammScheiner2014,
  author    = {Thamm, Markus and Scheiner, Ricarda},
  title     = {PKG in honey bees: spatial expression, amfor gene expression, sucrose responsiveness, and division of labor},
  series = {The journal of comparative neurology},
  volume    = {522},
  journal   = {The journal of comparative neurology},
  number    = {8},
  publisher = {Wiley-Blackwell},
  address   = {Hoboken},
  issn      = {0021-9967},
  doi       = {10.1002/cne.23500},
  pages     = {1786 -- 1799},
  year      = {2014},
  abstract  = {Division of labor is a hallmark of social insects. In honey bees, division of labor involves transition of female workers from one task to the next. The most distinct tasks are nursing (providing food for the brood) and foraging (collecting pollen and nectar). The brain mechanisms regulating this form of behavioral plasticity have largely remained elusive. Recently, it was suggested that division of labor is based on nutrition-associated signaling pathways. One highly conserved gene associated with food-related behavior across species is the foraging gene, which encodes a cyclic guanosine monophosphate (cGMP)-dependent protein kinase (PKG). Our analysis of this gene reveals the presence of alternative splicing in the honey bee. One isoform is expressed in the brain. Expression of this isoform is most pronounced in the mushroom bodies, the subesophageal ganglion, and the corpora allata. Division of labor and sucrose responsiveness in honey bees correlate significantly with foraging gene expression in distinct brain regions. Activating PKG selectively increases sucrose responsiveness in nurse bees to the level of foragers, whereas the same treatment does not affect responsiveness to light. These findings demonstrate a direct link between PKG signaling in distinct brain areas and division of labor. Furthermore, they demonstrate that the difference in sensory responsiveness between nurse bees and foragers can be compensated for by activating PKG. Our findings on the function of PKG in regulating specific sensory responsiveness and social organization offer valuable indications for the function of the cGMP/PKG pathway in many other insects and vertebrates. J. Comp. Neurol. 522:1786-1799, 2014. (c) 2013 Wiley Periodicals, Inc.},
  language  = {en}
}
@article{BehrendsScheiner2012,
  author    = {Behrends, Andreas and Scheiner, Ricarda},
  title     = {Octopamine improves learning in newly emerged bees but not in old foragers},
  series = {JOURNAL OF EXPERIMENTAL BIOLOGY},
  volume    = {215},
  journal   = {JOURNAL OF EXPERIMENTAL BIOLOGY},
  number    = {7},
  publisher = {COMPANY OF BIOLOGISTS LTD},
  address   = {CAMBRIDGE},
  issn      = {0022-0949},
  doi       = {10.1242/jeb.063297},
  pages     = {1076 -- 1083},
  year      = {2012},
  abstract  = {Honey bees (Apis mellifera) are well known for their excellent learning abilities. Although most age groups learn quickly to associate an odor with a sucrose reward, newly emerged bees and old foragers often perform poorly. For a long time, the reason for the poor learning performance of these age groups was unclear. We show that reduced sensitivity for sucrose is the cause for poor associative learning in newly emerged bees but not in old foragers. By increasing the sensitivity for sucrose through octopamine, we selectively improved the learning performance of insensitive newly emerged bees. Interestingly, the learning performance of foragers experiencing the same treatment remained low, despite the observed increase in sensitivity for the reward. We thus demonstrate that increasing sensitivity for the reward can improve the associative learning performance of bees when they are young but not when they had foraged for a long time. Importantly, octopamine can have very different effects on bees, depending on their initial sensory sensitivity. These differential effects of octopamine have important consequences for interpreting the action of biogenic amines on insect behavior.},
  language  = {en}
}
@article{Scheiner2012,
  author    = {Scheiner, Ricarda},
  title     = {Birth weight and sucrose responsiveness predict cognitive skills of honeybee foragers},
  series = {Animal behaviour},
  volume    = {84},
  journal   = {Animal behaviour},
  number    = {2},
  publisher = {Elsevier},
  address   = {London},
  issn      = {0003-3472},
  doi       = {10.1016/j.anbehav.2012.05.011},
  pages     = {305 -- 308},
  year      = {2012},
  abstract  = {Honeybees, Apis mellifera, can differ considerably in their birth weights but the consequences of these weight differences for behaviour are unknown. I investigated how these birth weight differences affected their cognitive skills when the bees reached foraging age. Individual sucrose responsiveness measured by the proboscis extension response is a strong determinant of appetitive olfactory learning performance in honeybees. Most of the observed learning differences between individuals or between genetic bee strains correlate with differences in their sucrose responsiveness. My second aim was therefore to investigate whether the sucrose responsiveness of newly emerged bees could predict the learning behaviour of the bees 3 weeks later. Both birth weight and sucrose responsiveness measured at emergence could predict olfactory learning scores as demonstrated by significant positive correlations. Heavy bees and bees with high sucrose responsiveness later learned better than lighter individuals or bees with lower responsiveness to sucrose at emergence. These results demonstrate for the first time a fundamental relationship between sensory responsiveness and morphology at emergence and later cognitive skills in insects. Because sensory responsiveness is closely linked to division of labour in honeybees, differences in weight and sucrose responsiveness at emergence might be involved in regulating division of labour.},
  language  = {en}
}
@misc{BlenauScheinerPlueckhahnetal.2002,
  author    = {Blenau, Wolfgang and Scheiner, Ricarda and Pl{\"u}ckhahn, Stephanie and Oney, Bahar and Erber, Joachim},
  title     = {Behavioural pharmacology of octopamine, tyramine and dopamine in honey bees},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-44308},
  year      = {2002},
  abstract  = {In the honey bee, responsiveness to sucrose correlates with many behavioural parameters such as age of first foraging, foraging role and learning. Sucrose responsiveness can be measured using the proboscis extension response (PER) by applying sucrose solutions of increasing concentrations to the antenna of a bee. We tested whether the biogenic amines octopamine, tyramine and dopamine, and the dopamine receptor agonist 2-amino-6,7-dihydroxy-1,2,3,4-tetrahydronaphthalene (6,7-ADTN) can modulate sucrose responsiveness. The compounds were either injected into the thorax or fed in sucrose solution to compare different methods of application. Injection and feeding of tyramine or octopamine significantly increased sucrose responsiveness. Dopamine decreased sucrose responsiveness when injected into the thorax. Feeding of dopamine had no effect. Injection of 6,7-ADTN into the thorax and feeding of 6,7-ADTN reduced sucrose responsiveness significantly. These data demonstrate that sucrose responsiveness in honey bees can be modulated by biogenic amines, which has far reaching consequences for other types of behaviour in this insect. (C) 2002 Elsevier Science B.V. All rights reserved.},
  language  = {en}
}