Identification of novel host factors via conserved domain search: Cns1 cochaperone is a novel restriction factor of tombusvirus replication in yeast.
Identification of novel host factors via conserved domain search: Cns1 cochaperone is a novel restriction factor of tombusvirus replication in yeast.
复制标题
通过保守域搜索鉴定新型宿主因子：Cns1 辅伴侣是酵母中烟草病毒复制的新型限制因子。
DOI：
10.1128/jvi.00196-13
复制
发表时间：
2013
影响因子：
5.4
通讯作者：
Nagy,PeterD
中科院分区：
文献类型：
--
作者：
Lin,Jing-Yi;Nagy,PeterD
大量宿主编码的蛋白质通过作为易感因子影响正链RNA病毒的复制。已知许多其他细胞蛋白质作为病毒感染的限制因子起作用。以前的研究与番茄丛矮番茄丛矮病毒（TBSV）在酵母模式宿主揭示了TPR（tetratricopeptide repeat）结构域的亲环素，这是一个大家族的成员，在TBSV复制的抑制功能。在本文中，我们测试了额外的TPR含酵母蛋白在无细胞TBSV复制试验，并确定了Cns1p cochaperone热休克蛋白70（Hsp70）和Hsp90伴侣作为一个强大的抑制剂TBSV复制。Cns1p与病毒复制蛋白相互作用，抑制病毒复制酶复合物的组装和病毒RNA的合成。Cns1p的过表达抑制了TBSV在酵母中的复制。使用温度敏感（TS）突变体的Cns1p在酵母中发现，在半允许的温度，TS Cns1p不能抑制TBSV复制。有趣的是，Cns1p和含有TPR的Cpr7p亲环蛋白在TBSV复制过程中具有相似的抑制功能，尽管它们的病毒限制机制的一些细节是不同的。我们的观察表明，含有TPR的细胞蛋白可以作为病毒的限制因子。
A large number of host-encoded proteins affect the replication of plus-stranded RNA viruses by acting as susceptibility factors. Many other cellular proteins are known to function as restriction factors of viral infections. Previous studies with tomato bushy stunt tombusvirus (TBSV) in a yeast model host have revealed the inhibitory function of TPR (tetratricopeptide repeat) domain-containing cyclophilins, which are members of the large family of host prolyl isomerases, in TBSV replication. In this paper, we tested additional TPR-containing yeast proteins in a cell-free TBSV replication assay and identified the Cns1p cochaperone for heat shock protein 70 (Hsp70) and Hsp90 chaperones as a strong inhibitor of TBSV replication. Cns1p interacted with the viral replication proteins and inhibited the assembly of the viral replicase complex and viral RNA synthesisin vitro. Overexpression of Cns1p inhibited TBSV replication in yeast. The use of a temperature-sensitive (TS) mutant of Cns1p in yeast revealed that at a semipermissive temperature, TS Cns1p could not inhibit TBSV replication. Interestingly, Cns1p and the TPR-containing Cpr7p cyclophilin have similar inhibitory functions during TBSV replication, although some of the details of their viral restriction mechanisms are different. Our observations indicate that TPR-containing cellular proteins could act as virus restriction factors.