Journal of Genetics

, 88:177

Cytogenetic characterization of Eurysternus caribaeus (Coleoptera: Scarabaeidae): evidence of sex-autosome fusion and diploid number reduction prior to species dispersion

Authors

  • Amanda Paulino De Arcanjo
    • Departamento de Biologia, Instituto de Ciências BiológicasUPE-Universidade de Pernambuco
  • Diogo Cavalcanti Cabral-De-Mello
    • Departamento de Morfologia, Instituto de BiociênciasUNESP-Universidade Estadual Paulista
  • Ana Emília Barros E. Silva
    • Departamento de Botânica, Centro de Ciências BiológicasUFPE-Universidade Federal de Pernambuco
  • Rita De Cássia De Moura
    • Departamento de Biologia, Instituto de Ciências BiológicasUPE-Universidade de Pernambuco
Research Article

DOI: 10.1007/s12041-009-0025-y

Cite this article as:
De Arcanjo, A.P., Cabral-De-Mello, D.C., Silva, A.E.B.E. et al. J Genet (2009) 88: 177. doi:10.1007/s12041-009-0025-y

Abstract

Mitotic and meiotic chromosomes of several populations of Eurysternus caribaeus (Coleoptera: Scarabaeidae) were analysed through conventional staining, C-banding, base-specific fluorochromes, silver nitrate staining and fluorescent in situ hybridization (FISH). All specimens showed 2n = 8 in their karyotypes, with a neo-XY sex system (Y is a submetacentric and X a metacentric) and three pairs of submetacentric autosomes. The analysis of constitutive heterochromatin (CH) revealed small blocks located in the centromeric region of all chromosomes which do not present positive staining under the fluorochromes CMA3 and DAPI. Silver nitrate staining revealed that the nucleolar organizer region (NORs) is associated with the sex chromosomes. The FISH technique revealed that rDNA sites in the X and Y are different in size. Data from different populations indicate that the diploid number reduction (2n = 8) observed in E. caribaeus is established and presumably has preceded the dispersion of this species. Moreover, this reduction occasioned the translocation of rDNA sites to the sex chromosomes, X and Y, an uncommon pattern in Scarabaeidae that was observed for the first time by the FISH in this work.

Keywords

chromosome rearrangementsFISHheterochromatinmeiosisNORs

Copyright information

© Indian Academy of Sciences 2009