Magori Shimpei, Citovsky Vitaly
Department of Biochemistry and Cell Biology, State University of New York, Stony Brook, NY, USA.
Biochim Biophys Acta. 2011 Aug;1809(8):388-94. doi: 10.1016/j.bbagrm.2011.01.007. Epub 2011 Feb 2.
To genetically transform plants, Agrobacterium transfers its T-DNA into the host cell and integrates it into the plant genome, resulting in neoplastic growths. Over the past 2 decades, a great deal has been learned about the molecular mechanism by which Agrobacterium produces T-DNA and transports it into the host nucleus. However, T-DNA integration, which is the limiting, hence, the most critical step of the transformation process, largely remains an enigma. Increasing evidence suggests that Agrobacterium utilizes the host DNA repair machinery to facilitate T-DNA integration. Meanwhile, it is well known that chromatin modifications, including the phosphorylation of histone H2AX, play an important role in DNA repair. Thus, by implication, such epigenetic codes in chromatin may also have a considerable impact on T-DNA integration, although the direct evidence to demonstrate this hypothesis is still lacking. In this review, we summarize the recent advances in our understanding of Agrobacterium T-DNA integration and discuss the potential link between this process and the epigenetic information in the host chromatin. This article is part of a Special Issue entitled: Epigenetic Control of cellular and developmental processes in plants.
为了对植物进行遗传转化，根癌农杆菌将其Ti质粒的转移DNA（T-DNA）导入宿主细胞并整合到植物基因组中，导致肿瘤生长。在过去的20年里，人们对根癌农杆菌产生T-DNA并将其转运到宿主细胞核中的分子机制有了很多了解。然而，T-DNA整合作为转化过程中的限制步骤，因此也是最关键的步骤，在很大程度上仍然是一个谜。越来越多的证据表明，根癌农杆菌利用宿主DNA修复机制促进T-DNA整合。同时，众所周知，包括组蛋白H2AX磷酸化在内的染色质修饰在DNA修复中起重要作用。因此，尽管仍缺乏直接证据来证明这一假设，但染色质中的这种表观遗传密码可能也对T-DNA整合有相当大的影响。在这篇综述中，我们总结了我们对根癌农杆菌T-DNA整合理解的最新进展，并讨论了这一过程与宿主染色质表观遗传信息之间的潜在联系。本文是名为：植物细胞和发育过程的表观遗传控制的特刊的一部分。
