HSV1立即早期基因ICP22的结构与功能分析

Of the five HSV1 immediate-early (IE) proteins, infected-cell protein 22 (ICP22), the product of the Us1 gene, is a member whose function is less understood than those of the other four IE proteins. In order to promote better understanding of the role of ICP22 in viral replication, mutation and fluorescence techniques were used to investigate the biochemical relationship between ICP22’s structure and nuclear localization, and the CAT assay was used to analyze the relationship between ICP22’s structure and its transcriptional repression. The results of these experiments implicated (1) ICP22 is localized to small dense nuclear bodies and in pairs with SC-35 domain in the nucleus, (2) ICP22 localization in a punctate state requires completion of N-terminal sequence, (3) the conservative mutation in nucleotidylation site is important for its nuclear localization and transcriptional repression, (4) Despite possessing the same amino acid sequence as the ICP22 carboxyl-terminal, Us1.5 was distincted from ICP22 in location an function.