Transposable elements drive species-specific and tissue-specific transcriptomes in human development

Abstract

BackgroundTransposable elements (TEs) are an abundant and crucial regulatory resource in the human genome. Serving as alternative promoters, TEs can be reactivated and produce TE-initiated transcripts, which play importance roles in early development and differentiated tissues. However, the prevalence and function of TE-initiated transcription in human development are poorly characterized. ResultsWe identified 12,918 TE-initiated transcripts across 40 human body sites and embryonic stem cells. Among TE-initiated transcripts, 80% were activated in a tissue-specific manner. TEs with tissue-specific transcription factor binding motifs were enriched in particular tissues. Additionally, approximately half of TE-derived TSSs were primates-specific. Notably, 375 primates-specific TE-derived TSSs were found to create novel tissue-specific gene expression patterns during evolution. ConclusionsOur results characterize the global profile of TE-initiated transcription and enhance our understanding of TE contribution to the primate-specific gene regulatory networks in human development.