Nucleotide sequence of an heterochromatic segment recognized by the antibodies to Z-DNA in fixed metaphase chromosomes

Open Access
Publisher Website
Google Scholar
Abstract
The purpose of this work was to analyse at the molecular level the DNA recognized by the antibodies to Z-NA in in situ experiments. Antibodies to Z-DNA interact strongly with R-band positive heterochromatic segments of fixed metaphase chromosomes of Cebus (Viegas-Pequignot et al., 1983). These segments are constituted of a satellite DNA the repeat unit of which is about 1520 base pairs long. The base sequence of the repeat unit has been determined. It contains a (AC)n rich region which, in vitro, adopts the Z conformation under topological constraints. Experiments with nuclei suggest that this sequence is not predominantly in the Z conformation in vivo. The polymorphic structure of the (AC)n rich region argues for an active recombination sequence.