Tuyển tập các báo cáo nghiên cứu về y học được đăng trên tạp chí y học quốc tế cung cấp cho các bạn kiến thức về ngành y đề tài: " The silent defense: Micro-RNA directed defense against HIV-1 replication. | Retrovirology BioMed Central Commentary Open Access The silent defense Micro-RNA directed defense against HIV-I replication Ajit Kumar Address Department of Biochemistry Molecular Biology George Washington University Washington USA Email Ajit Kumar - akumar@ Corresponding author Published 12 April 2007 Received 2 March 2007 Accepted 12 April 2007 Retrovirology 2007 4 26 doi 1742-4690-4-26 This article is available from http content 4 1 26 2007 Kumar licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License http licenses by which permits unrestricted use distribution and reproduction in any medium provided the original work is properly cited. Abstract MicroRNAs play critical role in regulating gene expression. MicroRNA profile of particular cell type bears the signature of cell type specific gene expression. Given that viral pathogens replicate by evading host defenses research is now focused on the miRNA-regulated genes that critically regulate HIV-1 propagation in human host cells. Background Ever since the initial report 1 that C. elegans lin-4 gene product a 21 nucleotide non-coding RNA ncRNA regulates the expression of lin-14 by partial complementarity to several regions within the 3 -UTR of the target lin-14 mRNA RNA-mediated gene silencing RNAi has taken on new urgency to understand its role in regulating gene expression in mammalian cells. A recent report in Science 2 argues that RNAi limits the replication of HIV-1 in human cells and that cellular micro-RNAs miRNAs contribute to this antiviral response. This report opens the inquiry into exciting new area of virus-host interaction and asks how viral infection overcomes the limitations imposed on virus life cycle by the host miRNA-mediated defenses. Nearly 500 human genes are known to encode 21 nucleotide miRNAs which are initially transcribed by RNA Polymerase II as .
