Tuyển tập các báo cáo nghiên cứu về y học được đăng trên tạp chí y học Wertheim cung cấp cho các bạn kiến thức về ngành y đề tài: Functional similarity analysis of human virusencoded miRNAs. | Yu and He Journal of Clinical Bioinformatics 2011 1 15 http content 1 1 15 JOURNAL OF CLINICAL BIOINFORMATICS RESEARCH Open Access Functional similarity analysis of human virus-encoded miRNAs Guangchuang Yu and Qing-Yu He Abstract miRNAs are a class of small RNAs that regulate gene expression via RNA silencing machinery. Some viruses also encode miRNAs contributing to the complex virus-host interactions. A better understanding of viral miRNA functions would be useful in designing new preventive strategies for treating diseases induced by viruses. To meet the challenge for how viruses module host gene expression by their encoded miRNAs we measured the functional similarities among human viral miRNAs by using a method we reported previously. Higher order functions regulated by viral miRNAs were also identified by KEGG pathway analysis on their targets. Our study demonstrated the biological processes involved in virus-host interactions via viral miRNAs. Phylogenetic analysis suggested that viral miRNAs have distinct evolution rates compared with their corresponding genome. Introduction miRNAs about 22 nucleotides in length constitute a large family of non-coding RNAs that regulate gene expression posttranscriptionally leading their target mRNAs to direct destructive cleavage or translational repression by base pairing with the 3 untranslated regions 3 UTRs . miRNA-mediated regulation plays crucial roles in a wide spectrum of biological processes including proliferation 1 apoptosis 2 development 3 immune system regulation 4 and oncogenesis 5 . Recent discoveries on viral miRNAs mostly in herpesvirus family 6 threw lights on a new level of cross-talk between virus and host in viral infections and pathogenesis 7 . Viral miRNAs have been reported to participate in immune evasion by directly down-regulating host immune defence genes and even to cooperate with viral proteins to target the same process 8 . The combination of protein-mediated and .
