The oligomerization domain of VP3, the scaffolding protein of infectious bursal disease virus, plays a critical role in capsid assembly
The oligomerization domain of VP3, the scaffolding protein of infectious bursal disease virus, plays a critical role in capsid assembly
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DOI：
10.1128/jvi.77.11.6438-6449.2003
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发表时间：
2003-06-01
影响因子：
5.4
通讯作者：
Rodriguez, JF
中科院分区：
文献类型：
--
作者：
Maraver, A;Oña, A;Rodriguez, JF
传染性法氏囊病病毒（IBDV）衣壳由含有三种多肽pVP2、VP2和VP3的单一蛋白层形成。在这里，我们发现在昆虫细胞中合成的VP3蛋白，无论是表达完整的多蛋白还是从VP3基因结构中合成的VP3蛋白，都会被蛋白水解降解，导致缺乏13个c末端残基的产物积累。这一发现导致在多肽c端附近的一个24个氨基酸的延伸内鉴定VP3寡聚化结构域，部分重叠VP1结合结构域。通过蛋白水解或多蛋白基因的缺失使VP3寡聚化结构域失活，可消除病毒样颗粒的形成。在同时表达多蛋白和VP1的双重重组杆状病毒感染的细胞中，VP3-VP1复合物的形成阻止了VP3蛋白的水解，并导致昆虫细胞中有效的病毒样颗粒的形成。
Infectious bursal disease virus (IBDV) capsids are formed by a single protein layer containing three polypeptides, pVP2, VP2, and VP3. Here, we show that the VP3 protein synthesized in insect cells, either after expression of the complete polyprotein or from a VP3 gene construct, is proteolytically degraded, leading to the accumulation of product lacking the 13 C-terminal residues. This finding led to identification of the VP3 oligomerization domain within a 24-amino-acid stretch near the C-terminal end of the polypeptide, partially overlapping the VP1 binding domain. Inactivation of the VP3 oligomerization domain, by either proteolysis or deletion of the polyprotein gene, abolishes viruslike particle formation. Formation of VP3-VP1 complexes in cells infected with a dual recombinant baculovirus simultaneously expressing the polyprotein and VP1 prevented VP3 proteolysis and led to efficient virus-like particle formation in insect cells.