title: Analysis of DNA endoreplication in the brain neurons in the terrestrial slug, Limax valentianus.
abstract: DNA endoreplication is the DNA synthesis without cell division, resulting in the generation of a nucleus containing a larger amount of genomic DNA compared to a normal diploid genome. There are many such giant neurons in the molluscan brain that are generated as a result of repeated endoreplication. However, it has been controversial whether the endoreplication is the whole genome replication (polyploidy) or the local amplification of the genes that are necessary for the neuron's function (polyteny/polysomy). Here in this study, we investigated these two possibilities by (1) immunohistochemical analysis of the distribution of 5'-bromodeoxyuridine incorporated into the nuclei of the brain neurons, and by (2) quantitative genomic PCR directed to two different genes expressed in specific brain regions. Our data supported the view that the DNA endoreplication is the whole genome replication rather than the local amplification of a specific genomic region.
authors: Kagawa School of Pharmaceutical Sciences, Tokushima Bunri University, 1314-1 Shido, Sanuki, Kagawa 769-2193, Japan. matsuor@kph.bunri-u.ac.jp
authors: R
authors: R
authors: Matsuo
authors: Miki
authors: M
authors: Yamagishi
authors: E
authors: E
authors: Ito
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001921:Brain / Q000166:cytology; D001973:Bromodeoxyuridine; D004261:DNA Replication; D049851:Gastropoda / Q000235:genetics / Q000378:metabolism*; D007150:Immunohistochemistry; D008969:Molecular Sequence Data; D009474:Neurons / Q000378:metabolism*; D016133:Polymerase Chain Reaction
chemical_list: D001973:Bromodeoxyuridine