RT Journal Article SR Electronic T1 Genome-Scale Sequence Disruption Following Biolistic Transformation in Rice and Maize JF The Plant Cell JO Plant Cell FD American Society of Plant Biologists SP 368 OP 383 DO 10.1105/tpc.18.00613 VO 31 IS 2 A1 Liu, Jianing A1 Nannas, Natalie J. A1 Fu, Fang-fang A1 Shi, Jinghua A1 Aspinwall, Brooke A1 Parrott, Wayne A. A1 Dawe, R. Kelly YR 2019 UL http://www.plantcell.org/content/31/2/368.abstract AB Biolistic transformation delivers nucleic acids into plant cells by bombarding the cells with microprojectiles, which are micron-scale, typically gold particles. Despite the wide use of this technique, little is known about its effect on the cell’s genome. We biolistically transformed linear 48-kb phage lambda and two different circular plasmids into rice (Oryza sativa) and maize (Zea mays) and analyzed the results by whole genome sequencing and optical mapping. Although some transgenic events showed simple insertions, others showed extreme genome damage in the form of chromosome truncations, large deletions, partial trisomy, and evidence of chromothripsis and breakage-fusion bridge cycling. Several transgenic events contained megabase-scale arrays of introduced DNA mixed with genomic fragments assembled by nonhomologous or microhomology-mediated joining. Damaged regions of the genome, assayed by the presence of small fragments displaced elsewhere, were often repaired without a trace, presumably by homology-dependent repair (HDR). The results suggest a model whereby successful biolistic transformation relies on a combination of end joining to insert foreign DNA and HDR to repair collateral damage caused by the microprojectiles. The differing levels of genome damage observed among transgenic events may reflect the stage of the cell cycle and the availability of templates for HDR.