Division of Plant Sciences, University of Missouri, Columbia, MO 65211, USA.
Virology. 2013 Sep 1;443(2):363-74. doi: 10.1016/j.virol.2013.05.028. Epub 2013 Jun 12.
The gene VI product, protein 6 (P6), of Cauliflower mosaic virus (CaMV) assembles into large, amorphous inclusion bodies (IBs) that are considered sites for viral protein synthesis and viral genome replication and encapsidation. P6 IBs align with microfilaments and require them for intracellular trafficking, a result implying that P6 IBs function to move virus complexes or virions within the cell to support virus physiology. Through a yeast two-hybrid screen we determined that CHUP1, a plant protein allowing chloroplast transport through an interaction with chloroplast and microfilament, interacts with P6. The interaction between CHUP1 and P6 was confirmed through colocalization in vivo and co-immunoprecipitation assays. A truncated CHUP1 fused with enhanced cyan fluorescent protein, unable to transport chloroplasts, inhibited intracellular movement of P6-Venus inclusions. Silencing of CHUP1 in N. edwardsonii impaired the ability of CaMV to infect plants. The findings suggest that CHUP1 supports CaMV infection through an interaction with P6.
花椰菜花叶病毒（CaMV）的基因 VI 产物，蛋白 6（P6），组装成大的无定形包含体（IB），这些包含体被认为是病毒蛋白合成和病毒基因组复制和包装的场所。P6 IB 与微丝对齐，并需要微丝进行细胞内运输，这一结果表明 P6 IB 发挥作用以将病毒复合物或病毒粒子在细胞内移动，以支持病毒生理学。通过酵母双杂交筛选，我们确定了 CHUP1，一种允许叶绿体通过与叶绿体和微丝相互作用进行转运的植物蛋白，与 P6 相互作用。通过体内共定位和共免疫沉淀实验证实了 CHUP1 和 P6 之间的相互作用。与增强型青色荧光蛋白融合的截短的 CHUP1 不能转运叶绿体，抑制了 P6-Venus 包含体的细胞内运动。在 N. edwardsonii 中沉默 CHUP1 会损害 CaMV 感染植物的能力。这些发现表明，CHUP1 通过与 P6 的相互作用支持 CaMV 感染。
