Jahangir Alam, Ruenphet Sakchai, Sultana Nadia, Shoham Dany, Takehara Kazuaki
Laboratory of Zoonoses, School of Veterinary Medicine, Kitasato University, Towada 034-8628, Japan ; Animal Health Research Division, Bangladesh Livestock Research Institute, Savar, Dhaka 1341, Bangladesh.
Influenza Res Treat. 2012;2012:847505. doi: 10.1155/2012/847505. Epub 2012 Dec 25.
The pandemic influenza virus strains of 1918 (H1N1), 1957 (H2N2), 1968 (H3N2), and 2009 (H1N1) have genes related to avian influenza viruses (AIVs). The nonstructural (NS) gene of AIVs plays a significant role in host-viral interaction. However, little is known about the degree of diversity of this gene in Northern pintail (Anas acuta) ducks wintering in Japan. This study describes characteristics of pintail-originated H1N1, H1N2, H1N3, H5N2, H5N3, H5N9, and H7N7 viruses. Most of the viruses were revealed to be avian strains and not related to pandemic and seasonal flu strains. Nevertheless, the NP genes of 62.5% (5/8) viruses were found closely related to a A/swine/Korea/C12/08, indicating exchange of genetic material and ongoing mammalian-linked evolution of AIVs. Besides, all the viruses, except Aomori/422/07 H1N1, contain PSIQSR∗GLF motif usually found in avian, porcine, and human H1 strains. The Aomori/422/07 H1N1 has a PSVQSR∗GLF motif identical to a North American strain. This findings linked to an important intercontinental, Asian-American biogeographical interface. Phylogenetically all the viruses were clustered in Eurasian lineage. Cocirculation of allele A and B (NS gene) viruses was evident in the study implying the existence of a wide reservoir of influenza A viruses in pintail wintering in Japan.
1918年（H1N1）、1957年（H2N2）、1968年（H3N2）和2009年（H1N1）的大流行性流感病毒株具有与禽流感病毒（AIVs）相关的基因。AIVs的非结构（NS）基因在宿主-病毒相互作用中起着重要作用。然而，对于在日本越冬的针尾鸭（Anas acuta）中该基因的多样性程度知之甚少。本研究描述了源自针尾鸭的H1N1、H1N2、H1N3、H5N2、H5N3、H5N9和H7N7病毒的特征。大多数病毒被发现是禽毒株，与大流行和季节性流感毒株无关。尽管如此，发现62.5%（5/8）的病毒的核蛋白（NP）基因与A/猪/韩国/C12/08密切相关，这表明AIVs存在遗传物质交换以及与哺乳动物相关的持续进化。此外，除青森/422/07 H1N1外，所有病毒都含有通常在禽、猪和人H1毒株中发现的PSIQSR∗GLF基序。青森/422/07 H1N1具有与北美毒株相同的PSVQSR∗GLF基序。这一发现与一个重要的洲际、亚洲-美洲生物地理界面相关。在系统发育上，所有病毒都聚集在欧亚谱系中。在本研究中，等位基因A和B（NS基因）病毒的共循环很明显，这意味着在日本越冬的针尾鸭中存在广泛的甲型流感病毒储存库。
