Age-related and steroid induced changes in the histones of the quail liver

Histones were extracted from the liver of young, adult and old Japanese quails. Both linker and core histones were found to vary with age. An extra band, H3X, was found between H2A and H4. Its level is higher in young and old birds in comparison to that of the adult. H3X shows interesting changes under steroid induction. Its level is higher in progesterone administered young birds. In adult and old birds, it is higher in progesterone treated (P) and progesterone primed estradiol administered (P+E) birds, and lower in all estradiol (E) and estradiol primed progesterone administered (E+P) birds. The relative levels of H3X in the steroid administered birds also vary with age. Such changes may influence chromatin conformation and gene expression.