Abstract
Fibroblasts of female Microtus agrestis were treated with 5-azadeoxycytidine (5-aza-dCyd) at a final concentration of 10−5 M during the last 2 h of culture. This cytidine analogue induces distinct undercondensation of the constitutive heterochromatin in the giant X chromosomes. The undercondensed heterochromatic thread exhibits longitudinal segmentation reminiscent of a chromomere pattern. In the late-replicating X chromosome, 5-aza-dCyd also inhibits condensation of the genetically inactivated euchromatin (facultative heterochromatin). The described effects of 5-aza-dCyd on the X chromosome structure appear to be incorporation independent.
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Haaf, T., Schmid, M. 5-Azadeoxycytidine induced undercondensation in the giant X chromosomes of Microtus agrestis . Chromosoma 98, 93–98 (1989). https://doi.org/10.1007/BF00291043
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DOI: https://doi.org/10.1007/BF00291043