Proliferation pattern of postembryonic neuroblasts in the brain of Drosophila melanogaster.
The spatio-temporal proliferation pattern of postembryonic neuroblasts in the central brain region of the supra-esophageal ganglion of Drosophila melanogaster was studied by labeling DNA replicating cells with 5-bromo-2'-deoxyuridine (BrdU). There are five proliferating neuroblasts per hemisphere in larvae just after hatching: one in the ventro-lateral, and the other four in the postero-dorsal region of the brain. Dividing neuroblasts increase during the late first-late second instar larval stages, reaching a plateau of about 85 neuroblasts per hemisphere. Most neuroblasts cease dividing 20-30 hr after puparium formation (APF), while only four in the postero-dorsal region continue making progenies until 85-90 hr APF. The four distinct neuroblasts proliferating in the early larval and late pupal stages are identical; they lie in the cortex above the calyces of the mushroom bodies (corpora pedunculata), proliferating over a period twice as long as that for the other neuroblasts. Their daughter neurons project into the mushroom body neuropile, and hence are likely to be the Kenyon cells. The cell-cycle period of the four neuroblasts (named mushroom body neuroblasts: MBNbs) is rather constant (1.1-1.5 hr) during the mid larval-early pupal stages and is longer before and after that. The total number of the MBNb progenies made throughout the embryonic and postembryonic development was estimated to be 800-1200 per hemisphere.
Ito
K
K
Department of Physics, Faculty of Science, University of Tokyo, Japan.
Hotta
Y
Y
D000818:Animals; D001921:Brain / Q000166:cytology / Q000187:drug effects / Q000254:growth & development; D001973:Bromodeoxyuridine / Q000494:pharmacology; D002453:Cell Cycle; D002455:Cell Division; D004247:DNA / Q000096:biosynthesis; D004261:DNA Replication; D004331:Drosophila melanogaster / Q000235:genetics / Q000254:growth & development*; D007814:Larva / Q000166:cytology; D009474:Neurons / Q000502:physiology*; D011679:Pupa / Q000166:cytology
D004247:DNA; D001973:Bromodeoxyuridine