Atallah Osama O, Kang Sung-Hwan, El-Mohtar Choaa A, Shilts Turksen, Bergua María, Folimonova Svetlana Y
University of Florida, Plant Pathology Department, Gainesville, FL 32611, USA.
University of Florida, Plant Pathology Department, Gainesville, FL 32611, USA.
Virology. 2016 Feb;489:108-15. doi: 10.1016/j.virol.2015.12.008. Epub 2015 Dec 31.
Superinfection exclusion (SIE), a phenomenon in which a primary virus infection prevents a secondary infection with the same or closely related virus, has been observed with various viruses. Earlier we demonstrated that SIE by Citrus tristeza virus (CTV) requires viral p33 protein. In this work we show that p33 alone is not sufficient for virus exclusion. To define the additional viral components that are involved in this phenomenon, we engineered a hybrid virus in which a 5'-proximal region in the genome of the T36 isolate containing coding sequences for the two leader proteases L1 and L2 has been substituted with a corresponding region from the genome of a heterologous T68-1 isolate. Sequential inoculation of plants pre-infected with the CTV L1L2T68 hybrid with T36 CTV resulted in superinfection with the challenge virus, which indicated that the substitution of the L1-L2 coding region affected SIE ability of the virus.
超级感染排除（SIE）是一种主要病毒感染可阻止相同或密切相关病毒的二次感染的现象，已在多种病毒中观察到。此前我们证明，柑橘衰退病毒（CTV）引起的超级感染排除需要病毒p33蛋白。在这项研究中，我们发现单独的p33不足以实现病毒排除。为了确定参与这一现象的其他病毒成分，我们构建了一种杂种病毒，其中T36分离株基因组中包含两个前导蛋白酶L1和L2编码序列的5'近端区域已被来自异源T68-1分离株基因组的相应区域所取代。用CTV L1L2T68杂种病毒预先感染植物，然后依次接种T36 CTV，结果挑战病毒发生了超级感染，这表明L1-L2编码区域的替换影响了病毒的超级感染排除能力。
