The 100K-chaperone protein from adenovirus serotype 2 (subgroup C) assists in trimerization and nuclear localization of hexons from subgroups C and B adenoviruses
The 100K-chaperone protein from adenovirus serotype 2 (subgroup C) assists in trimerization and nuclear localization of hexons from subgroups C and B adenoviruses
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DOI：
10.1016/j.jmb.2005.06.070
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发表时间：
2005-09-09
影响因子：
5.6
通讯作者：
Chroboczek, J
中科院分区：
文献类型：
--
作者：
Hong, SS;Szolajska, E;Chroboczek, J
来自C亚群腺病毒（Ad 2和Ads）和来自B亚群腺病毒（Ad 3）的成员的重组六邻体已经在昆虫细胞中表达。当单独表达时，发现所有三个六邻体都是不溶性的，并在细胞质中作为包涵体积累。然而，重组Ad 2、Ads或Ad 3六邻体与Ad 2 L4- 100 K蛋白的共表达导致可溶性三聚体六邻体的形成。六邻体的EM分析显示，它们与从Ad 2感染的人细胞分离的或从部分破坏的腺病毒体释放的天然六邻体衣壳体是不可区分的。这表明100 K在昆虫细胞中充当六邻体折叠和自组装成壳粒的伴侣。由于100 K蛋白有助于亚群C六邻体和亚群B六邻体蛋白的三聚化，这意味着它以同型和异型的方式起作用。在重组蛋白表达过程中，发现100 K蛋白与细胞质内的六邻体单体和三聚体相关联。然而，在细胞核中，100 K仅在与六邻体三聚体的复合物中发现。对纯化的100 K蛋白样品的EM观察显示与单体蛋白相容的哑铃形分子。六邻体-100 K蛋白质复合物的EM分析表明，六邻体与100 K蛋白质的相互作用通过100 K蛋白质分子的球状结构域之一发生。我们的数据证实了100 K蛋白作为六邻体的支架蛋白的作用，并提供证据表明其在昆虫细胞六邻体核输入中的功能。(c)2005爱思唯尔有限公司保留所有权利。
Recombinant hexons from subgroup C adenoviruses (Ad2 and Ads) and from a member of subgroup B (Ad3) adenoviruses have been expressed in insect cells. When expressed alone, all three hexons were found to be insoluble and accumulated as inclusion bodies in the cytoplasm. However, co-expression of recombinant Ad2, Ads or Ad3 hexon with Ad2 L4-100K protein resulted in the formation of soluble trimeric hexons. EM analysis of hexons revealed that they were indistinguishable from native hexon capsomers isolated from Ad2-infected human cells, or released from partially disrupted adenovirions. This suggests that 100K acts as a chaperone for hexon folding and self-assembly into capsomer in insect cells. Since 100K protein assists in the trimerization of subgroup C hexon, and of subgroup B hexon protein, it implies that it functions in a manner that is both homo- and heterotypic. During the course of recombinant protein expression, the 100K protein was found in association with hexon monomers and trimers within the cytoplasm. In the nucleus, however, 100K was found in complexes with hexon trimers exclusively. EM observation of purified 100K protein samples showed a dumb-bell-shaped molecule compatible with a monomeric protein. EM analysis of hexon-100K protein complexes showed that interaction of hexon with the 100K protein occurred via one of the globular domains of the 100K protein molecule. Our data confirm the role of the 100K protein as a scaffold protein for hexon, and provide evidence suggesting its function in hexon nuclear import in insect cells. (c) 2005 Elsevier Ltd. All rights reserved.