title: Three-dimensional network of Drosophila brain hemisphere.
abstract: The first step to understanding brain function is to determine the brain's network structure. We report a three-dimensional analysis of the brain network of the fruit fly Drosophila melanogaster by synchrotron-radiation tomographic microscopy. A skeletonized wire model of the left half of the brain network was built by tracing the three-dimensional distribution of X-ray absorption coefficients. The obtained models of neuronal processes were classified into groups on the basis of their three-dimensional structures. These classified groups correspond to neuronal tracts that send long-range projections or repeated structures of the optic lobe. The skeletonized model is also composed of neuronal processes that could not be classified into the groups. The distribution of these unclassified structures correlates with the distribution of contacts between neuronal processes. This suggests that neurons that cannot be classified into typical structures should play important roles in brain functions. The quantitative description of the brain network provides a basis for structural and statistical analyses of the Drosophila brain. The challenge is to establish a methodology for reconstructing the brain network in a higher-resolution image, leading to a comprehensive understanding of the brain structure.
authors.affiliation: Department of Applied Biochemistry, School of Engineering, Tokai University, Kitakaname, Hiratsuka, Kanagawa 259-1292, Japan. Electronic address: ryuta@tokai-u.jp.
authors.forename: Ryuta
authors.initials: R
authors.lastname: Mizutani
authors.forename: Rino
authors.initials: R
authors.lastname: Saiga
authors.forename: Akihisa
authors.initials: A
authors.lastname: Takeuchi
authors.forename: Kentaro
authors.initials: K
authors.lastname: Uesugi
authors.forename: Yoshio
authors.initials: Y
authors.lastname: Suzuki
mesh_terms: D000818:Animals; D001921:Brain / Q000000981:diagnostic imaging / Q000648:ultrastructure; D004331:Drosophila melanogaster / Q000648:ultrastructure*; D055032:Electron Microscope Tomography; D021621:Imaging, Three-Dimensional; D008954:Models, Biological; D009415:Nerve Net / Q000000981:diagnostic imaging / Q000648:ultrastructure*; D055114:X-Ray Microtomography
keywords: Brain; Microtomography; Model building; Network; micro-CT