Identification of transcription factor binding sites derived from transposable element sequences using ChIP-seq.

Transposable elements (TEs) form a substantial fraction of the non-coding DNA of many eukaryotic genomes. There are numerous examples of TEs being exapted for regulatory function by the host, many of which were identified through their high conservation. However, given that TEs are often the youngest part of a genome and typically exhibit a high turnover, conservation-based methods will fail to identify lineage- or species-specific exaptations. ChIP-seq has become a very popular and effective method for identifying in vivo DNA-protein interactions, such as those seen at transcription factor binding sites (TFBS), and has been used to show that there are a large number of TE-derived TFBS. Many of these TE-derived TFBS show poor conservation and would go unnoticed using conservation screens. Here, we describe a simple pipeline method for using data generated through ChIP-seq to identify TE-derived TFBS.