皮托病毒被重复入侵,这有助于它们的进化和从雪松病毒分离
Sofia Rigou1, Alain Schmitt1, Jean-Marie Alempic1
1Information Génomique & Structurale, Unité Mixte de Recherche 7256 (Institut de Microbiologie de la Méditerranée, FR3479), IM2B, IOM, Aix-Marseille University, Centre National de la Recherche Scientifique, Marseille 13288 Cedex 9, France.
Molecular biology and evolution
|November 11, 2023
概括
感染阿米巴的巨型病毒Pithoviridae显示出具有独特组织的保存基因组. 基因组大小的变化是由基因重复和反向重复驱动的,特别是在pithoviruses中,影响它们的进化.
科学领域:
- 病毒学 病毒学
- 基因组学就是基因组学.
- 进化生物学 进化生物学
背景情况:
- 皮索病毒 (Pithoviridae) 是以其大颗粒量而闻名的巨型病毒,感染阿米巴.
- 皮索病毒 (Pithovirus sibericum) 首次在古老的永久土中被发现,相关病毒在不同的环境中被发现.
研究的目的:
- 为了对Pithoviridae家族进行比较基因组分析.
- 了解这些巨型病毒的基因组组织和进化动态.
主要方法:
- 隔离和基因组测序新的Pithoviridae和cedratviruses分离物.
- 对12个可用的Pithoviridae基因组进行比较基因组分析.
- 使用专门的生物信息管道识别重复丰富的区域.
主要成果:
- 皮索维里代基因组表现出具有核心基因和基因重复区域的不均结构.
- 这些病毒具有相对保守的基因组,水平基因转移率低 (5-7%).
- 基因组大小的变化主要是由于基因重复 (14-28%) 和广泛的反向重复入侵,特别是在pithoviruses.
结论:
- 匹多病毒群的基因组以不同的组织模式和进化机制为特征.
- 反向重复是pithoviruses中基因组变异和进化的重要驱动因素,但在cedratviruses中没有.
- 富含重复的区域充当突变,基因捕获和重新排列的热点,塑造了皮索病毒的进化.
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