tailieunhanh - Báo cáo y học: "Nucleolar localization of influenza A NS1: striking differences between mammalian and avian cells"

Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành y học dành cho các bạn tham khảo đề tài: Nucleolar localization of influenza A NS1: striking differences between mammalian and avian cells | Volmer et al. Virology Journal 2010 7 63 http content 7 1 63 VIROLOGY JOURNAL SHORT REPORT Open Access Nucleolar localization of influenza A NS1 striking differences between mammalian and avian cells D I I m ZM 1 2D r I h z -s 7 I C- 1 -f 1 -1-71 2 3 krirb ll -1 I m J V1 2 0 r í r 1 X IV I c r I I L . i .r-1 2 . rd I I r VI 1 2 Romain voimer Beryl Mazel-oancnez Cnrisielle volmer Sébasiien M soubies Jean-Luc Guérin Abstract In mammalian cells nucleolar localization of influenza A NS1 requires the presence of a C-terminal nucleolar localization signal. This nucleolar localization signal is present only in certain strains of influenza A viruses. Therefore only certain NS1 accumulate in the nucleolus of mammalian cells. In contrast we show that all NS1 tested in this study accumulated in the nucleolus of avian cells even in the absence of the above described C-terminal nucleolar localization signal. Thus nucleolar localization of NS1 in avian cells appears to rely on a different nucleolar localization signal that is more conserved among influenza virus strains. Findings The nucleolus is a highly dynamic multifunctional sub-nuclear compartment 1 . It is the site of ribosomal RNA synthesis and ribosomal subunits assembly. In addition the nucleolus is increasingly recognized as a critical regulator of many other cellular functions including the regulation of mitosis cell growth and response to stress 1-3 . The nucleolus is also emerging as an important target of various viral proteins 4 . Viral proteins targeting the nucleolus are for example implicated in the regulation of apoptosis as shown with West Nile virus capsid protein and in the regulation of viral mRNA export as shown with human immunodeficiency virus Rev protein and with herpesvirus saimiri ORF57 protein 5-7 . However for most viruses consequences of viral protein localization in the nucleolus remain largely unknown 3 4 . The non-structural 1 NS1 protein of influenza A viruses NS1 is a .