TY - JOUR T1 - The regulatory landscape of early maize inflorescence development JF - bioRxiv DO - 10.1101/870378 SP - 870378 AU - Rajiv K. Parvathaneni AU - Edoardo Bertolini AU - Md Shamimuzzaman AU - Daniel Vera AU - Pei-Yau Lung AU - Brian R. Rice AU - Patrick J. Brown AU - Alexander E. Lipka AU - Hank W. Bass AU - Andrea L. Eveland Y1 - 2019/01/01 UR - http://biorxiv.org/content/early/2019/12/10/870378.abstract N2 - The functional genome of agronomically important plant species remains largely unexplored, yet presents a virtually untapped resource for targeted crop improvement. Functional elements of regulatory DNA revealed through profiles of chromatin accessibility can be harnessed for fine-tuning gene expression to optimal phenotypes in specific environments. Here, we investigate the non-coding regulatory space in the maize (Zea mays) genome during early reproductive development of pollen- and grain-bearing inflorescences. Using an assay for differential sensitivity of chromatin to micrococcal nuclease (MNase) digestion, we profiled accessible chromatin and nucleosome occupancy in these largely undifferentiated tissues and classified approximately 1.6 percent of the genome as accessible, with the majority of MNase hypersensitive sites marking proximal promoters, but also 3’ ends of maize genes. This approach mapped regulatory elements to footprint-level resolution. Integration of complementary transcriptome profiles and transcription factor (TF) occupancy data were used to annotate regulatory factors, such as combinatorial TF binding motifs and long non-coding RNAs, that potentially contribute to organogenesis, including tissue-specific regulation between male and female inflorescence structures. Finally, genome-wide association studies for inflorescence architecture traits based only on functional regions delineated by MNase hypersensitivity revealed new SNP-trait associations in known regulators of inflorescence development as well as new candidates. These analyses provide a comprehensive look into the cis-regulatory landscape during inflorescence differentiation in a major cereal crop, which ultimately shapes architecture and influences yield potential. ER -