Mapping polycomb-repressed domains in the bithorax complex using in vivo formaldehyde cross-linked chromatin

Valerio Orlando*, Renato Paro

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

301 Scopus citations


The Polycomb group (Pc-G) proteins are responsible for keeping developmental regulators, like homeotic genes, stably and inheritably repressed during Drosophila development. Several similarities to a protein class involved in heterochromatin formation suggest that the Pc-G exerts its function at the higher order chromatin level. Here we have mapped the distribution of the Pc protein in the homeotic bithorax complex (BX-C) of Drosophila tissue culture cells. We have elaborated a method, based on the in vivo formaldehyde cross-linking technique, that allows a substantial enrichment for Pc-interacting sites by immunoprecipitation of the cross-linked chromatin with anti-Pc antibodies. We find that the Pc protein quantitatively covers large regulatory regions of repressed BX-C genes. Conversely, we find that the Abdominal-B gene is active in these cells and the region devold of any bound Pc protein.

Original languageEnglish (US)
Pages (from-to)1187-1198
Number of pages12
Issue number6
StatePublished - Dec 17 1993

ASJC Scopus subject areas

  • Biochemistry, Genetics and Molecular Biology(all)

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