Unveiling the cryptic diversity and distribution of elements related to virophage mavirus through deep mining of pPolB proteins

Yutong Wei; Qiyan Liu; Zhen Gong; Guan-Zhu Han

doi:10.1016/j.virs.2026.03.009

April 2026

. doi: 10.1016/j.virs.2026.03.009

Citation: Yutong Wei, Qiyan Liu, Zhen Gong, Guan-Zhu Han. Unveiling the cryptic diversity and distribution of elements related to virophage mavirus through deep mining of pPolB proteins .VIROLOGICA SINICA, 2026, 41(2) : 371-381. http://dx.doi.org/10.1016/j.virs.2026.03.009

基于pPolB蛋白挖掘与噬病毒体Mavirus相关元件的多样性与分布

南京师范大学生命科学学院

通讯作者： 宫震, gongzhen@nnu.edu.cn; 韩管助, guanzhu@njnu.edu.cn
收稿日期： 2025-12-22
录用日期： 2026-03-20

摘要

噬病毒体(virophages)是一类独特的双链DNA病毒，寄生于核质大病毒(Nucleocytoviricota, NCVs)。尽管传统上将其视为一个独立的病毒类群，但越来越多的证据表明，“噬病毒体”更应被理解为一种寄生生活方式，而非一个自然群体。尽管存在这一概念上的转变，但关于其多样性与演化历程的认识在很大程度上仍模糊不清且充满争议。研究通过对全球范围内7041个真核生物基因组和12053个宏基因组中的携带B型DNA聚合酶(pPolB)进行深度挖掘，极大地扩展了pPolB的噬病毒体Mavirus相关元件(pMVREs)的多样性，其中包括噬病毒体、转座病毒(transpovirons)以及类Polinton病毒(PLVs)。系统发育基因组学与宏基因组学挖掘显示，pMVREs在真核生物基因组(97/7041，占比1.38%)及全球宏基因组样本(2450/12053，占比20.33%)中广泛分布。这些元件呈现出高度可塑性与混杂性的基因组结构。无论在真核生物基因组层面还是全球宏基因组层面，pMVREs与NCVs的存在均展现出统计学上显著的相关性，这为两者之间存在特定的共现关联提供了有力支持。此外，pMVREs的多样性与群落组成在全球不同生态系统中表现出显著异质性。综上所述，本研究揭示了一个极为多样化的噬病毒体相关元件，为深入理解噬病毒体、转座病毒、类Polinton病毒、pMVREs以及NCVs之间错综复杂的关系提供了新的见解。
- 病毒学
- , 病毒进化
- , 病毒生态学
- , 宏基因组

Unveiling the cryptic diversity and distribution of elements related to virophage mavirus through deep mining of pPolB proteins

College of Life Sciences, Nanjing Normal University, Nanjing 210023, China

Corresponding author: Zhen Gong, gongzhen@nnu.edu.cn Guan-Zhu Han, guanzhu@njnu.edu.cn
Received Date: 22 December 2025
Accepted Date: 20 March 2026

Abstract

Virophages are unique double-stranded DNA (dsDNA) viruses that parasitize viruses of Nucleocytoviricota (NCVs). While conventionally viewed as a viral group, growing evidence suggests that “virophage” is better understood as a parasitic lifestyle, rather than a natural group. Despite this conceptual shift, their diversity and evolution remain largely obscure and contentious. Through deep mining of protein-primed type B DNA polymerase (pPolB) in 7041 eukaryotic genomes and 12,053 metagenomes sampled globally, we expand the diversity of pPolB-carrying mavirus virophage-related elements (pMVREs), which include virophages, transpovirons, and Polinton-like viruses (PLVs). Our phylogenomic and metagenomic mining reveals the widespread distribution of pMVREs in eukaryotic genomes (97/7041, 1.38%) and global environments (2450/12053, 20.33%). pMVREs possess genome architectures of high plasticity and promiscuity. The presence of pMVREs and NCVs is statistically correlated in both eukaryotic genomes and global metagenomes, supporting a specific co-occurrence association between pMVREs and NCVs. Moreover, pMVRE diversity and composition exhibit strong heterogeneity across global ecosystems. Together, this study unveils a vast diversity of virophage-related elements and provides insights into the intricate relationship among virophages, transpovirons, PLVs, pMVREs, and NCVs.
- Virophages
- , Virus evolution
- , Virus ecology
- , Metagenomes

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