Synapsis, recombination, and chromatin remodeling in the XY body of armadillos.
Chromosome Res
; 20(2): 293-302, 2012 Feb.
Article
em En
| MEDLINE
| ID: mdl-22274548
ABSTRACT
Three xenarthrans species Chaetophractus villosus, Chaetophractus vellerosus, and Zaedyus pichiy have been used for the analysis of the structure, behavior, and immunochemical features of the XY body during pachytene. In all these species, the sex chromosomes form an XY body easily identifiable in thin sections by the special and regular packing of the chromatin fibers of the internal region of the XY body ("differential" regions) and those of the peripheral region (synaptic region). Spermatocyte spreads show a complete synapsis between the X- and the Y-axis, which lasts up to the end of pachytene. From the early pachytene substages to the late ones, the X-axis develops prominent branches, which in late pachytene span the synaptic region. Synapsis is regular as shown by SYCP1 labeling. Axial development is followed by SYCP3 labeling and in the asynaptic region of the X-axis by BRCA1. Gamma-H2AX labels exclusively the differential (asynaptic) region of the X chromosome. A single focus is labeled by MLH1 in the synaptic region. The location of this MLH1 focus spans from 0.3 to 1.6 µm from the telomere in the analyzed xenarthrans, covering approximately half of the Y-axis length. It is concluded that xenarthrans, as basal placental mammals, harbor the largest pseudoautosomal regions of presently analyzed mammals, and shows the typical features of meiotic sex chromosome inactivation (MSCI).
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Tatus
/
Recombinação Genética
/
Pareamento Cromossômico
/
Montagem e Desmontagem da Cromatina
Limite:
Animals
Idioma:
En
Revista:
Chromosome Res
Assunto da revista:
BIOLOGIA MOLECULAR
Ano de publicação:
2012
Tipo de documento:
Article
País de afiliação:
Argentina