Genome-Wide Characterization of the Accessible Chromatin Regions in Chickpea

Chromatin accessibility is important for genome architecture and gene expression in plants. In this study, the ATAC-seq method was utilized to identify accessible chromatin regions (ACRs) across the chickpea (Cicer arietinum) genome, an important legume crop cultivated worldwide. A total of 11,555 ACRs were identified in the chickpea genome, enriched at gene transcription start sites (TSS) and positively correlated with gene expression. Furthermore, as expected, a number of known transcription factor (TF) binding motifs were enriched in these ACRs. Integrating histone modification data, ACRs were found to be closely associated with H3K27ac and H3K4me3 modifications to regulate gene expression. In addition, the gain and loss of ACRs have been demonstrated to have significant effects on the expression of homologous genes. Collectively, this study provides a comprehensive understanding of the genomic function of ACRs in chickpea.