Abstract：
Introns containing homing endonucleases are widespread in nature and have long been assumed to be selfish elements that provide no benefit to the host organism. These genetic elements are common in viruses, but whether they confer a selective advantage is unclear. In this work, we studied intron-encoded homing endonuclease gp210 in bacteriophage ΦPA3 and found that it contributes to viral competition by interfering with the replication of a coinfecting phage, ΦKZ. We show that gp210 targets a specific sequence in ΦKZ, which prevents the assembly of progeny viruses. This work demonstrates how a homing endonuclease can be deployed in interference competition among viruses and provide a relative fitness advantage. Given the ubiquity of homing endonucleases, this selective advantage likely has widespread evolutionary implications in diverse plasmid and viral competition as well as virus-host interactions.
摘要：
含有归巢核酸内切酶的内含子在自然界中很普遍，长期以来一直被认为是对宿主生物体没有益处的自私元件。这些遗传因子在病毒中很常见,但它们是否赋予选择性优势尚不清楚。在这项工作中,我们在噬菌体ΦPA3中研究了内含子编码的归巢核酸内切酶gp210，发现它通过干扰共感染噬菌体的复制而促进病毒竞争，ΦKZ。我们证明gp210靶向ΦKZ中的特定序列，阻止子代病毒的组装。这项工作证明了如何在病毒之间的干扰竞争中部署归巢核酸内切酶并提供相对的适应性优势。鉴于归巢核酸内切酶的普遍存在，这种选择性优势可能在不同质粒和病毒竞争以及病毒-宿主相互作用中具有广泛的进化意义.
