NOR sites detected by Ag-dAPI staining of an unusual autosome chromosome of Bradysia hygida (Diptera:Sciaridae) colocalize with C-banded heterochromatic region.
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.
Gaspar
Vanessa Pinatto
VP
Departamento de Biologia Celular e Genética, Universidade Estadual de Maringá, Paraná, Brasil.
Borges
Alex Rodrigues
AR
Fernandez
Maria Aparecida
MA
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
D006570:Heterochromatin; D007211:Indoles; C007293:DAPI