Efficient Preparation of High-Complexity ChIP-Seq Profiles from Early Xenopus Embryos.

Chromatin immunoprecipitation followed by next-generation sequencing (ChIP-seq) has become a powerful tool to acquire a precise and genome-wide snapshot of many chromatin features in vivo. These chromatin profiles are obtained by immunoprecipitation of cross-linked chromatin fragments to enrich the feature of interest. Sequencing and aligning the underlying DNA sequences to the genome make it possible to virtually reconstruct the global distribution of most chromatin features. We present here recent improvements to the ChIP-seq protocol by means of Xenopus embryos to prepare high-complexity DNA libraries from small amounts of biological material. This approach allows researchers to explore the landscape of chromatin regulators and states in early vertebrate embryos or in any biological entity with small numbers of cells.