The coupling of synthesis and partitioning of EBV's plasmid replicon is revealed in live cells

作者：Asuka Nanbo, Arthur U. Sugden, Bill Sugden · 发表于：The EMBO Journal · 年份：2007 · DOI：10.1038/sj.emboj.7601853 · 被引用次数：193 · 研究领域：Viral-associated cancers and disorders、Cytomegalovirus and herpesvirus research、Immune Cell Function and Interaction

Epstein-Barr virus (EBV) is an exceptionally successful human viral pathogen maintained as a licensed, plasmid replicon in proliferating cells. We have measured the distributions of EBV-derived plasmids in single live cells throughout the cell cycle in the absence of selection and confirmed the measured rates of duplication and partitioning computationally and experimentally. These analyses have uncovered a striking, non-random partitioning for this minimalist plasmid replicon and revealed additional properties of it and its host cells: (1) 84% of the plasmids duplicate during each S phase; (2) all duplicated plasmids are spatially colocalized as pairs, a positioning that is coupled to their non-random partitioning; (3) each clone of cells requires a certain threshold number of plasmids per cell for its optimal growth under selection; (4) defects in plasmid synthesis and partitioning are balanced to yield wide distributions of plasmids in clonal populations of cells for which the plasmids provide a selective advantage. These properties of its plasmid replicon underlie EBV's success as a human pathogen.