Meiotic studies in Dysdercus Guerin Meneville 1831 (Heteroptera: Pyrrhocoridae). I. Neo-XY in Dysdercus albofasciatus Berg 1878, a new sex chromosome determining system in Heteroptera

The genus Dysdercus Guerin Meneville 1831 represents the only taxon within the family Pyrrhocoridae in the New World. Based on morphological features, it has been suggested that American species derived from immigrants from the Old World, most probably from the Ethiopian Region. So far, 10 species f...

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Detalles Bibliográficos
Autores principales: Bressa, M.J., Papeschi, A.G., Mola, L.M., Larramendy, M.L.
Formato: JOUR
Materias:
Dysdercus albofasciatus
Heteroptera
Holokinetic chromosomes
Neo-XY
Pyrrhocoridae
amino acid sequence
animal cell
article
autosome
chromosome analysis
chromosome number
diploidy
insect
meiosis
metaphase
nonhuman
priority journal
sex chromosome
X chromosome
Animals
Karyotyping
Male
Meiosis
X Chromosome
Y Chromosome
Animalia
Arachnida
Dysdercus
Hexapoda
Insecta
Acceso en línea:http://hdl.handle.net/20.500.12110/paper_09673849_v7_n7_p503_Bressa
Aporte de:
Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA) de Universidad de Buenos Aires
Descripción
Sumario:The genus Dysdercus Guerin Meneville 1831 represents the only taxon within the family Pyrrhocoridae in the New World. Based on morphological features, it has been suggested that American species derived from immigrants from the Old World, most probably from the Ethiopian Region. So far, 10 species from Dysdercus, including six species from the Old World and four species from the Neotropical Region have been cytogenetically analyzed. As is characteristic of Heteroptera, they possess holokinetic chromosomes and a prereductional type of meiosis. While the X1X2O sex chromosome system has been reported in all cytologically analyzed species of Dysdercus from the Old World, the system X0 has been found in all but one species from the New World, regardless of the number of autosomes in the complement. In the present study the male meiosis of D. albofasciatus Berg 1878 was studied in specimens from four different populations from Argentina. The diploid chromosome number was found to be 2n = 10 + neo-XY. The neo-X shows at each subterminal region a positively heteropycnotic and DAPI-bright segment which corresponds to the ancestral X-chromosome. The origin of this neo-XY system involved, most probably, a subterminal insertion of the ancestral X chromosome in an autosome, followed by a large inversion, which included part of the original X chromosome.

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