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bioRxiv · 10.1101/104372

T-DNA integration is rapid and influenced by the chromatin state of the host genome.

Shilo, S.·Tripathi, P.·Melamed-Bessudo, C.·Tzfadia, O.·Muth, T. R.·Levy, A. A.
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Abstract

Agrobacterium tumefaciens mediated T-DNA integration is a common tool for plant genome manipulation. However, there is controversy regarding whether T-DNA integration is biased towards genes or randomly distributed throughout the genome. In order to address this question, we performed high-throughput mapping of T-DNA-genome junctions obtained in the absence of selection at several time points after infection. T-DNA-genome junctions were detected as early as 6 hours post-infection. T-DNA distribution was apparently uniform throughout the chromosomes, yet local biases toward AT-rich motifs and T-DNA border sequence micro-homology were detected. Analysis of the epigenetic landscape of integration showed that selected events reported on previously were associated with extremely low methylation and nucleosome occupancy. Conversely, non-selected events from this study showed chromatin marks, such as high nucleosome occupancy and high H3K27me3 that correspond to 3D-interacting heterochromatin islands embedded within euchromatin. Such structures might play a role in capturing and silencing invading T-DNA.

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Shilo, S., Tripathi, P., Melamed-Bessudo, C., Tzfadia, O., Muth, T. R., Levy, A. A.. 2017-01-31. T-DNA integration is rapid and influenced by the chromatin state of the host genome.. https://doi.org/10.1101/104372

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