López-Bueno Alberto, Mavian Carla, Labella Alejandro M, Castro Dolores, Borrego Juan J, Alcami Antonio, Alejo Alí
Centro de Biología Molecular Severo Ochoa (Consejo Superior de Investigaciones Científicas and Universidad Autónoma de Madrid), Cantoblanco, Madrid, Spain.
Universidad de Málaga, Departamento de Microbiología, Campus Universitario Teatinos, Málaga, Spain.
J Virol. 2016 Sep 12;90(19):8768-79. doi: 10.1128/JVI.01369-16. Print 2016 Oct 1.
Lymphocystis disease is a geographically widespread disease affecting more than 150 different species of marine and freshwater fish. The disease, provoked by the iridovirus lymphocystis disease virus (LCDV), is characterized by the appearance of papillomalike lesions on the skin of affected animals that usually self-resolve over time. Development of the disease is usually associated with several environmental factors and, more frequently, with stress conditions provoked by the intensive culture conditions present in fish farms. In gilthead sea bream (Sparus aurata), an economically important cultured fish species in the Mediterranean area, a distinct LCDV has been identified but not yet completely characterized. We have used direct sequencing of the virome of lymphocystis lesions from affected S. aurata fish to obtain the complete genome of a new LCDV-Sa species that is the largest vertebrate iridovirus sequenced to date. Importantly, this approach allowed us to assemble the full-length circular genome sequence of two previously unknown viruses belonging to the papillomaviruses and polyomaviruses, termed Sparus aurata papillomavirus 1 (SaPV1) and Sparus aurata polyomavirus 1 (SaPyV1), respectively. Epidemiological surveys showed that lymphocystis disease was frequently associated with the concurrent appearance of one or both of the new viruses. SaPV1 has unique characteristics, such as an intron within the L1 gene, and as the first member of the Papillomaviridae family described in fish, provides evidence for a more ancient origin of this family than previously thought.
Lymphocystis disease affects marine and freshwater fish species worldwide. It is characterized by the appearance of papillomalike lesions on the skin that contain heavily enlarged cells (lymphocysts). The causative agent is the lymphocystis disease virus (LCDV), a large icosahedral virus of the family Iridoviridae In the Mediterranean area, the gilthead sea bream (Sparus aurata), an important farmed fish, is frequently affected. Using next-generation sequencing, we have identified within S. aurata lymphocystis lesions the concurrent presence of an additional LCDV species (LCDV-Sa) as well as two novel viruses. These are members of polyomavirus and papillomavirus families, and here we report them to be frequently associated with the presence of lymphocysts in affected fish. Because papillomaviruses have not been described in fish before, these findings support a more ancient origin of this virus family than previously thought and evolutionary implications are discussed.
淋巴囊肿病是一种在地理上广泛传播的疾病，影响超过150种不同的海洋和淡水鱼类。该疾病由虹彩病毒淋巴囊肿病病毒（LCDV）引发，其特征是受感染动物的皮肤上出现乳头状瘤样病变，这些病变通常会随着时间自行消退。疾病的发展通常与多种环境因素有关，更常见的是与养鱼场密集养殖条件引发的应激状况有关。在金头鲷（Sparus aurata）中，一种在地中海地区具有重要经济价值的养殖鱼类，已鉴定出一种独特的LCDV，但尚未完全表征。我们通过对受感染的金头鲷鱼淋巴囊肿病变的病毒组进行直接测序，获得了一种新的LCDV-Sa物种的完整基因组，这是迄今为止测序的最大的脊椎动物虹彩病毒。重要的是，这种方法使我们能够组装出两种先前未知病毒的全长环状基因组序列，它们分别属于乳头瘤病毒和多瘤病毒，被称为金头鲷乳头瘤病毒1（SaPV1）和金头鲷多瘤病毒1（SaPyV1）。流行病学调查表明，淋巴囊肿病经常与这两种新病毒中的一种或两种同时出现有关。SaPV1具有独特的特征，例如L1基因内有一个内含子，并且作为鱼类中描述的乳头瘤病毒科的首个成员，为该病毒科的起源比先前认为的更为古老提供了证据。
淋巴囊肿病影响全球范围内的海洋和淡水鱼类物种。其特征是皮肤上出现乳头状瘤样病变，其中含有严重肿大的细胞（淋巴囊肿）。病原体是淋巴囊肿病病毒（LCDV），一种属于虹彩病毒科的大型二十面体病毒。在地中海地区，重要的养殖鱼类金头鲷经常受到影响。通过下一代测序，我们在金头鲷淋巴囊肿病变中鉴定出同时存在另一种LCDV物种（LCDV-Sa）以及两种新型病毒。它们是多瘤病毒和乳头瘤病毒科的成员，在此我们报告它们经常与受感染鱼类中淋巴囊肿的存在有关。由于此前尚未在鱼类中描述过乳头瘤病毒，这些发现支持了该病毒科的起源比先前认为的更为古老的观点，并讨论了其进化意义。
