Analisis Molekuler Gen NS1 Virus Avian Influenza H5N1 yang Diisolasi dari Unggas Asal Purworejo Jawa Tengah dan Bantul Daerah Istimewa Yogyakarta

Abstract

Pathogenesis of infection of H5N1 virus involves hyperinduction of pro inflammatory cytokines which causes the cytokine storm. Although multigenic, NS1 gene can contribute to the level of virulence and or cytokine resistance. In this study, the NS1 gene fragment of H5N1 isolated from chicken and muscovy duck in Central Java and Yogyakarta, respectively, were analyzed. Phylogenetic analyses were performed in comparison to sequence data of H5N1 viruses from 29 bird isolates and 32 human isolates which were accessed from gene bank in the period of 1997 to 2007. Molecular characterization of amino acid sequences (64-173) revealed a common characteristic of highly pathogenic avian influenza namely, 5 codon deletion (80-84 position). The D92E mutation was not found in these isolates. Phylogenetic analysis demonstrated that the two genetic sequences from A/Chicken/Purworejo/2005 and A/Muscovyduck/Bantul/2005 have the closest relationship with level of confidence bootstrap value (1000 replicates) as 97.9%. Moreover, the two isolates have closer genetic relationship with isolates from Indonesia than from outside of Indonesia. There is no significant difference between NS1 gene fragment sequence motif between birds and human isolates. Three dimensional structure analyses displayed that deletion 80-84 is able to change protein structure of NS1.