Systematic analysis of the neural circuits in the associative regions of the Drosophila brain

• Project/Area Number: 16370067
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Biophysics
• Research Institution: The University of Tokyo
• Principal Investigator: ITO Kei The University of Tokyo, Institute of Molecular and Cellular Biosciences, Assosiate Professor, 分子細胞生物学研究所, 助教授 (00311192)
• Project Period (FY): 2004 – 2005
• Project Status: Completed (Fiscal Year 2005)
• Budget Amount: ¥14,500,000 (Direct Cost: ¥14,500,000); Fiscal Year 2005: ¥7,000,000 (Direct Cost: ¥7,000,000); Fiscal Year 2004: ¥7,500,000 (Direct Cost: ¥7,500,000)
• Keywords: Drosophila / insect / brain / neural circuit / associative region / GAL4 enhancer trap / mushroom body / central complex / 脳神経回路 / 傘部 / 葉部

Research Abstract

To elucidate the anatomical basis underlying the role of the associative regions of the insect brain such as the mushroom body (MB), we studied how the MB of Drosophila is organized by its intrinsic and extrinsic neurons. We screened for the GAL4 enhancer-trap strains that label specific subsets of these neurons, and identified seven subtypes of the Kenyon cells and three other putative intrinsic neurons. We found a small subregion of the calyx, into which only a specific subtype of the Kenyon cells arborize. Kenyon cells divide the pedunculus into at least five concentric strata. The α', β', α and β lobes are each divided into three strata, whereas the γlobe appears more homogeneous. As for the MB extrinsic neurons (MBENs), we found three types of antennal lobe projection neurons among which two types are novel, and 13 other types of MBENs that arborize in the calyx, lobes, and pedunculus. The lobe-associated MBENs arborize in only specific areas of the lobes along their longitudinal axes, forming two to five segmented zones in each lobe. The laminar arrangement of the Kenyon cell axons and transverse arborization of the MBENs together divide the lobes into smaller synaptic units. Arborization patterns of each type of identified neurons within and outside of the MB were analyzed in detail. Our study suggests that, although Kenyon cells form rectilinear structure throughout the longitudinal axis of the lobes, the segmented organization of the MBENs may facilitate different ways of interaction between intrinsic and extrinsic neurons and might therefore result in different functional activity along the longitudinal lobe axes and between lobes.

Research Products

• [Journal Article] Distinct memory traces for two visual features in the Drosophila brain. (2006)
  • Author(s): Lui, G., Seiler, H., Wen, A., Zars, T., Ito, K., Wolf, R., Heisenberg, M., Lui, L.
  • Journal Title: Nature 439 Pages: 551-556
  • Description: 「研究成果報告書概要(和文)」より
• [Journal Article] Essential role of the apoptotic cell engulfment genes draper and ced-6 in programmed axon pruning during Drosophila metamorphosis. (2006)
  • Author(s): Awasaki, T., Tatsumi, R., Takahashi, K., Arai, K., Nakanishi, Y., Ueda, R., Ito, K.
  • Journal Title: Neuron 50 Pages: 855-867
  • Description: 「研究成果報告書概要(和文)」より
• [Journal Article] Integration of chemosensory pathways in the Drosophila second-order olfactory centers. (2006)
  • Author(s): Akalal, D.B., Wilson, C.F., Zong, L., Tanaka, N.K., Ito, K., Davis, R.L
  • Journal Title: Learning and Memory 13 Pages: 659-668
  • Description: 「研究成果報告書概要(和文)」より
• [Journal Article] Distinct memory traces for two visual features in the Drosophila brain. (2006)
  • Author(s): Liu, G., Seiler, H., Wen, A., Zars, T., Ito, K., Wolf, R., Heisenberg, M., Liu, L.
  • Journal Title: Nature 439 Pages: 551-556
  • Description: 「研究成果報告書概要(欧文)」より
• [Journal Article] Roles for Drosophila mushroom body neurons in olfactory learning and memory. (2006)
  • Author(s): Akalal, D.B., Wilson, C.F., Zong, L., Tanaka, N.K., Ito, K., Davis, R.L.
  • Journal Title: Learning and Memory 13 Pages: 659-668
  • Description: 「研究成果報告書概要(欧文)」より
• [Journal Article] Distinct memory traces for two visual features in the Drosophila brain (2006)
  • Author(s): Liu.G., Seiler, H., Wen, A., Zars, T., Ito, K., Wolf, R., Heisenberg, M., Liu, L.
  • Journal Title: Nature 439 Pages: 551-556