Identification and characterization of two closely related unclassifiable endogenous retroviruses in pythons (Python molurus and Python curtus)
Identification and characterization of two closely related unclassifiable endogenous retroviruses in pythons (Python molurus and Python curtus)
复制标题
DOI：
10.1128/jvi.76.15.7607-7615.2002
复制
发表时间：
2002-08-01
影响因子：
5.4
通讯作者：
Schüpbach, J
中科院分区：
文献类型：
--
作者：
Huder, JB;Böni, J;Schüpbach, J
体包涵体病（BIBD）是一种怀疑由逆转录病毒引起的体蛇的致命疾病。为了鉴定该因子，评估了白细胞培养物（从具有BIBD症状的蟒蛇标本中建立或与此类患病动物一起饲养）的逆转录酶（RT）活性。显示出高RT活性的培养物中的病毒在蔗糖密度梯度上条带化，RT峰部分进行高效的程序，用于鉴定未知颗粒相关的逆转录病毒RNA。一个7 kb的完整的逆转录病毒序列进行了鉴定，克隆和测序。该病毒含有完整的gag、pro、pol和env的开放阅读框（ORF），以及pol内另一个功能未知的ORF。系统发育分析表明，该病毒与B和D型以及哺乳动物C型病毒都有较远的亲缘关系，但不能分类。它是目前作为一个高度表达的内源性逆转录病毒在所有P. molurus个体;一个密切相关的，但表达少得多的病毒被发现在所有测试的蟒蛇curtus个体。所有其他测试的体蛇，包括蟒蛇王，蟒蛇网纹，蟒蛇，Eunectes notaeus和莫雷利亚spilota，病毒阴性，独立于他们是否有BIBD。从软体动物中分离的病毒不能传播到B的外周血单个核细胞。constrictor或P. regius。因此，没有迹象表明，这种新的病毒，我们建议命名为蟒蛇内源性逆转录病毒（PyERV），是因果关系与BIBD。
Boid inclusion body disease (BIBD) is a fatal disorder of boid snakes that is suspected to be caused by a retrovirus. In order to identify this agent, leukocyte cultures (established from Python molurus specimens with symptoms of BIBD or kept together with such diseased animals) were assessed for reverse transcriptase (RT) activity. Virus from cultures exhibiting high RT activity was banded on sucrose density gradients, and the RT peak fraction was subjected to highly efficient procedures for the identification of unknown particle-associated retroviral RNA. A 7-kb full retroviral sequence was identified, cloned, and sequenced. This virus contained intact open reading frames (ORFs) for gag, pro, pol, and env, as well as another ORF of unknown function within pol. Phylogenetic analysis showed that the virus is distantly related to viruses from both the B and D types and the mammalian C type but cannot be classified. It is present as a highly expressed endogenous retrovirus in all P. molurus individuals; a closely related, but much less expressed virus was found in all tested Python curtus individuals. All other boid snakes tested, including Python regius, Python reticulatus, Boa constrictor, Eunectes notaeus, and Morelia spilota, were virus negative, independent of whether they had BIBD or not. Virus isolated from P. molurus could not be transmitted to the peripheral blood mononuclear cells of B. constrictor or P. regius. Thus, there is no indication that this novel virus, which we propose to name python endogenous retrovirus (PyERV), is causally linked with BIBD.