title: NOR sites detected by Ag-dAPI staining of an unusual autosome chromosome of Bradysia hygida (Diptera:Sciaridae) colocalize with C-banded heterochromatic region.
abstract: The study of chromosomes in insects is a good tool in mitotic process analysis, zoographic localization and evolution investigation. Among them, the Sciaridae offers a karyotype with a small number of chromosomes, where the heterochromatin and nucleolar organizer region, NOR, are easily analyzed in metaphase chromosomes obtained from cerebral ganglia squashes. In this work, the heterochromatic regions on Bradysia hygida mitotic chromosomes, revealed by C-banding, were identified as centromeric blocks on A and C chromosomes and as dark interstitial region in B and X chromosomes. By Ag-DAPI staining, active nucleolus organizer region, NOR, was revealed associated to the constitutive heterochromatin in the end of the C autosome chromosome. The C-band regions and the unusual ribosomal site localization are discussed.
authors: Departamento de Biologia Celular e Genética, Universidade Estadual de Maringá, Paraná, Brasil.
authors: Vanessa Pinatto
authors: VP
authors: Gaspar
authors: Alex Rodrigues
authors: AR
authors: Borges
authors: Maria Aparecida
authors: MA
authors: Fernandez
mesh_terms: D000818:Animals; D002503:Centromere; D002871:Chromosome Banding; D002875:Chromosomes / Q000648:ultrastructure; D004175:Diptera / Q000235:genetics*; D005260:Female; D005724:Ganglia / Q000648:ultrastructure; D006570:Heterochromatin / Q000648:ultrastructure; D007211:Indoles / Q000737:chemistry*; D008297:Male; D008677:Metaphase; D009697:Nucleolus Organizer Region / Q000648:ultrastructure*; D016622:Silver Staining; D013687:Telencephalon / Q000648:ultrastructure; D014960:X Chromosome / Q000648:ultrastructure
chemical_list: D006570:Heterochromatin; D007211:Indoles; C007293:DAPI