tailieunhanh - Báo cáo khoa học: " A conserved predicted pseudoknot in the NS2A-encoding sequence of West Nile and Japanese encephalitis flaviviruses suggests NS1' may derive from ribosomal frameshifting"

Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành y học dành cho các bạn tham khảo đề tài: A conserved predicted pseudoknot in the NS2A-encoding sequence of West Nile and Japanese encephalitis flaviviruses suggests NS1' may derive from ribosomal frameshifting | Virology Journal BioMed Central Open Access Short report A conserved predicted pseudoknot in the NS2A-encoding sequence of West Nile and Japanese encephalitis flaviviruses suggests NS1 may derive from ribosomal frameshifting Andrew E Firth 1 and John F Atkins 1 2 Address 1BioSciences Institute University College Cork Cork Ireland and 2Department of Human Genetics University of Utah Salt Lake City UT 84112-5330 USA Email Andrew E Firth - John F Atkins - Corresponding authors Published 5 February 2009 Received 21 December 2008 Accepted 5 February 2009 Virology journal 2009 6 14 doi l743-422X-6-l4 This article is available from http content 6 l l4 2009 Firth and Atkins 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__ Japanese encephalitis West Nile Usutu and Murray Valley encephalitis viruses form a tight subgroup within the larger Flavivirus genus. These viruses utilize a single-polyprotein expression strategy resulting in l0 mature proteins. Plotting the conservation at synonymous sites along the polyprotein coding sequence reveals strong conservation peaks at the very 5 end of the coding sequence and also at the 5 end of the sequence encoding the NS2A protein. Such peaks are generally indicative of functionally important non-coding sequence elements. The second peak corresponds to a predicted stable pseudoknot structure whose biological importance is supported by compensatory mutations that preserve the structure. The pseudoknot is preceded by a conserved slippery heptanucleotide Y CCU UUU thus forming a classical stimulatory motif for -l ribosomal frameshifting. We hypothesize .