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82 de Belle, J. S. & Heisenberg, M. Associative odor learning in Drosophila abolished by chemical ablation of mushroom bodies. Science 263, 692–695 (1994).In this study, the mushroom bodies of flies were chemically ablated to show that these structures have a definitive role in olfactory-based shock-avoidance learning.

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84 Zars, T., Fischer, M., Schulz, R. & Heisenberg, M. Localization of a short-term memory in Drosophila. Science 288, 672–675 (2000).These authors showed that synaptic plasticity in a small region of the mushroom bodies was sufficient for memory formation. They targeted expression of a rut+ transgene in a rut− background to regions of the adult brain.

85 Dubnau, J., Grady, L., Kitamoto, T. & Tully, T. Disruption of neurotransmission in Drosophila mushroom body blocks retrieval but not acquisition of memory. Nature 411, 476–480 (2001).This paper shows that synaptic transmission between mushroom body neurons is required during memory retrieval, but not during its acquisition or storage.

86 Bartsch, D. et al. Enhancement of memory-related long-term facilitation by ApAF, a novel transcription factor that acts downstream from both CREB1 and CREB2. Cell 103, 595–608 (2000).

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91 Quinn, W. G., Sziber, P. P. & Booker, R. The Drosophila memory mutant amnesiac. Nature 277, 212–214 (1979).

92 Feany, M. B. & Quinn, W. G. A neuropeptide gene defined by the Drosophila memory mutant amnesiac. Science 268, 869–873 (1995).

93 Waddell, S., Armstrong, J. D., Kitamoto, T., Kaiser, K. & Quinn, W. G. The amnesiac gene product is expressed in two neurons in the Drosophila brain that are critical for memory. Cell 103, 805–813 (2000).

94 Rosay, P., Armstrong, J. D., Wang, Z. & Kaiser, K. Synchronized neural activity in the Drosophila memory centers and its modulation by amnesiac. Neuron 30, 759–770 (2001).References 91–94 present the identification, cloning and spatial requirements of the putative neuropetide amnesiac and its role in memory.

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96 Yin, J. C. P., Vecchio, M. D., Zhou, H. & Tully, T. CREB as a memory modulator: induced expression of a dCREB2 isoform enhances long-term memory in Drosophila. Cell 81, 107–115 (1995).References 95 and 96 define a role for CREB in long-term memory. The dominant-negative CREB transgene had opposing effects on long-term memory to that of the CREB overexpressing transgene.

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105 Boynton, S. & Tully, T. latheo, a new gene involved in associative learning and memory in Drosophila melanogaster identified from P element mutagenesis. Genetics 131, 655–672 (1992).

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115 Wang, Y. et al. Genetic manipulation of the odor-evoked distributed neural activity in the Drosophila mushroom body. Neuron 29, 267–276 (2001).

116 Sokolowski, M. B. in Techniques for the Genetic Analysis of Brain and Behavior (eds Goldowitz, D., Wahlsten D. & Wimer, R. E.) 497 (Elsevier, Amsterdam, 1992).

117 Sokolowski, M. B. & Wahlsten, D. in Methods in Genomic Neuroscience (ed. Moldin, S. O.) 3–27 (CRC Press, New York, 2001).

118 Kaneko, M., Hamblen, M. J. & Hall, J. C. Involvement of the period gene in developmental time-memory: effect of the perShort mutation on phase shifts induced by light pulses delivered to Drosophila larvae. J. Biol. Rhythms 15, 13–30 (2000).

119 de Belle, J. S. & Heisenberg, M. Expression of Drosophila mushroom body mutations in alternative genetic backgrounds: a case study of the mushroom body miniature gene (mbm). Proc. Natl Acad. Sci. USA 93, 9875–9880 (1996).This is the only paper to have systematically tested for genetic background effects on a behaviour, in this case learning.

120 Davis, R. L. Mushroom bodies, Ca(2+) oscillations, and the memory gene amnesiac. Neuron 30, 653–656 (2001).