美国印第安纳大学Ankur B. Dalia等研究人员利用自然转化过程中DNA整合的时空分析，揭示了细菌的非遗传遗传模式。相关论文发表在2019年12月12日出版的《细胞》上。

研究人员开发了一种细胞生物学方法来表征霍乱弧菌在自然转化（NT）期间同源重组的时空动态。研究人员的结果直接证明：（1）转化的DNA以单链DNA的形式有效地整合到基因组中；（2）产生的异源双链体通过染色体复制和分离而得以解决；（3）整合的DNA在细胞分裂之前迅速表达。 研究人员表明，这些特性的组合导致转化人群中基因产物的非遗传转移，这可以促进霍乱弧菌和肺炎链球菌中抗生素耐药性的表型遗传。因此，除了从遗传上获得新的DNA序列外，NT还可以在这种保守的水平基因转移机制中促进性状的非遗传遗传。

研究人员表示，自然转化（NT）是微生物物种中水平基因转移的主要机制，可促进抗生素抗性决定簇和毒力因子的扩散。

附：英文原文

Title: Spatiotemporal Analysis of DNA Integration during Natural Transformation Reveals a Mode of Nongenetic Inheritance in Bacteria

Author: Ankur B. Dalia, Triana N. Dalia

Issue&Volume: 2019/12/12

Abstract: Natural transformation (NT) is a major mechanism of horizontal gene transfer in microbialspecies that promotes the spread of antibiotic-resistance determinants and virulencefactors. Here, we develop a cell biological approach to characterize the spatiotemporaldynamics of homologous recombination during NT in Vibrio cholerae. Our results directly demonstrate (1) that transforming DNA efficiently integratesinto the genome as single-stranded DNA, (2) that the resulting heteroduplexes areresolved by chromosome replication and segregation, and (3) that integrated DNA israpidly expressed prior to cell division. We show that the combination of these propertiesresults in the nongenetic transfer of gene products within transformed populations,which can support phenotypic inheritance of antibiotic resistance in both V. cholerae and Streptococcus pneumoniae. Thus, beyond the genetic acquisition of novel DNA sequences, NT can also promotethe nongenetic inheritance of traits during this conserved mechanism of horizontalgene transfer.

DOI: 10.1016/j.cell.2019.11.021

Source: https://www.cell.com/cell/fulltext/S0092-8674(19)31277-2