INVESTIGADORES
PIGOZZI Maria Ines
artículos
Título:
Heterochromatin and histone modifications in the germline-restricted chromosome of the zebra finch undergoing elimination during spermatogenesis
Autor/es:
GODAY C; PIGOZZI MI
Revista:
Chromosoma
Editorial:
SPRINGER
Referencias:
Año: 2010 vol. 119 p. 325 - 336
ISSN:
0009-5915
Resumen:
In the zebra finch (Taeniopygia guttata) a germline-restricted chromosome (GRC) is regularly present in males and females. While the GRC is euchromatic in oocytes, in spermatocytes this chromosome is cytologically seen as entirely heterochromatic and presumably inactive. At the end of male meiosis, the GRC is eliminated from the nucleus. By immunofluorescence on microspreads, we investigated HP1 proteins and histone modifications throughout male meiotic prophase, as well as in young spermatid stages after the GRC elimination. We found that in prophase spermatocytes the GRC chromatin differs from that of the regular chromosome complement. The GRC is highly enriched in HP1â and exhibits high levels of di- and tri-methylated histone H3 at lysine 9 and tri- and dimethylated histone H4 at lysine 20. The GRC does not exhibit neither detectable levels of di- and tri-methylated histone H3 at lysine 4 nor acetylated histone H4 at lysine 5 and 8. The results prove the heterochromatic organization of the GRC in male germline and strongly suggest its transcriptional inactive state during male prophase.
