Swaminathan Sankar
Department of Medicine, University of Florida Shands Cancer Center, Gainesville, Florida 32610, USA.
J Cell Biochem. 2005 Jul 1;95(4):698-711. doi: 10.1002/jcb.20465.
The Epstein-Barr virus (EBV) SM protein is a member of a highly conserved family of proteins present in most mammalian herpes viruses. There is a significant amount of functional and sequence divergence among the homologs encoded by the human herpes viruses, including differences in mechanism of action and varying effects on splicing and transcription. Nevertheless, in those cases where it has been studied, these proteins are essential for lytic replication of the virus. The mechanism by which SM regulates gene expression operates at the level of mRNA stability, processing, and export. SM enhances expression of EBV lytic genes and has both positive and negative effects on cellular gene expression. In addition to enhancing accumulation of EBV gene mRNAs, SM has important effects on cellular mRNAs, altering the host cell gene expression profile to facilitate viral replication. This article describes the current state of knowledge regarding the role of EBV SM in cellular and viral gene regulation and summarizes some of the similarities and differences with the ORF57 homolog from Kaposi's sarcoma-associated herpes virus (KSHV/HHV8).
爱泼斯坦-巴尔病毒（EBV）的SM蛋白是大多数哺乳动物疱疹病毒中存在的一个高度保守的蛋白家族的成员。人类疱疹病毒编码的同源物之间存在大量功能和序列差异，包括作用机制的差异以及对剪接和转录的不同影响。然而，在已研究的那些情况下，这些蛋白对于病毒的裂解复制至关重要。SM调节基因表达的机制在mRNA稳定性、加工和输出水平上起作用。SM增强EBV裂解基因的表达，并且对细胞基因表达有正负两方面的影响。除了增强EBV基因mRNA的积累外，SM对细胞mRNA也有重要影响，改变宿主细胞基因表达谱以促进病毒复制。本文描述了关于EBV SM在细胞和病毒基因调控中作用的当前知识状态，并总结了与卡波西肉瘤相关疱疹病毒（KSHV/HHV8）的ORF57同源物的一些异同。
