Department of Biochemistry and Cell Biology, Stony Brook University, Stony Brook, NY, 11794-5215, USA; College of Life Sciences, South China Agricultural University, Guangzhou, China.
Department of Biochemistry and Cell Biology, Stony Brook University, Stony Brook, NY, 11794-5215, USA.
Biochem Biophys Res Commun. 2021 May 21;554:7-12. doi: 10.1016/j.bbrc.2021.03.044. Epub 2021 Mar 25.
Agrobacterium T-DNA (transfer DNA) integration into the plant genome relies mostly on host proteins involved in the DNA damage repair pathways. However, conflicting results have been obtained using plants with mutated or down-regulated genes involved in these pathways. Here, we chose a different approach by following the expression of a series of genes, encoding proteins involved in the DNA damage response, during early stages of Agrobacterium infection in tobacco. First, we identified tobacco homologs of Arabidopsis genes induced upon DNA damage and demonstrated that their expression was activated by bleomycin, a DNA-break causing agent. Then, we showed that Agrobacterium infection induces the expression of several of these genes markers of the host DNA damage response, with different patterns of transcriptional response. This induction largely depends on Agrobacterium virulence factors, but not on the T-DNA, suggesting that the DNA damage response activation may rely on Agrobacterium-encoded virulence proteins. Our results suggest that Agrobacterium modulates the plant DNA damage response machinery, which might facilitate the integration of the bacterial T-DNA into the DNA breaks in the host genome.
农杆菌 T-DNA（转移 DNA）整合到植物基因组主要依赖于参与 DNA 损伤修复途径的宿主蛋白。然而，使用涉及这些途径的突变或下调基因的植物得到了相互矛盾的结果。在这里，我们通过在烟草中农杆菌感染的早期阶段跟踪一系列编码参与 DNA 损伤反应的蛋白质的基因的表达，采用了一种不同的方法。首先，我们鉴定了拟南芥基因在 DNA 损伤诱导的烟草同源物，并证明它们的表达被 DNA 断裂剂博莱霉素激活。然后，我们表明农杆菌感染诱导这些基因的表达，这些基因是宿主 DNA 损伤反应的标志物，具有不同的转录反应模式。这种诱导在很大程度上取决于农杆菌毒力因子，但不取决于 T-DNA，这表明 DNA 损伤反应的激活可能依赖于农杆菌编码的毒力蛋白。我们的结果表明，农杆菌调节植物 DNA 损伤反应机制，这可能有助于将细菌 T-DNA 整合到宿主基因组的 DNA 断裂中。
