Molecular characteristics and genetic evolution analysis of four strains of H1N1 subtype swine influenza viruses in different regions
Lu Wei
Yan Xijun
Zhao Gang
Yang Zuofeng
Zhang Yingxue
Zhang Xiuhua
Su Weiwei
Chen Chaoyang
Abstract：The research aims to understand the genetic variation of swine influenza virus(SIV)in different regions.After collecting the diseased materials of pigs suspected of being infected with SIV from different regions,virus isolation was carried out.The whole genome sequencing of the four isolated strains of H1N1 subtype SIV was performed,and molecular characteristics,homology and genetic evolution analyses were conducted.The results showed that the hemagglutinin(HA)and neuraminidase(NA)genes of the four virus strains belonged to the Eurasian avian type H1N1(EA H1N1)lineage,and the PB2,PB1,PA,NP,and M genes belonged to the 2009 pandemic H1N1(pdm/09 H1N1)lineage.The NS gene belongs to the classical H1N1 subtype(CS H1N1)lineage.The homologies of HA and NA genes of the four isolated strains were 92.8%～96.0%and 93.0%～96.7%respectively,and the amino acid homologies were 92.9%～95.9%and 93.2%～96.8%respectively.The cleavage sites of HA protein in the four isolated strains were all PSIQSRGL,and they had amino acid sites binding to the mammalian α-2,6-galactose(SAα-2,6-GAL)receptor.Key amino acid site variations related to virulence have occurred in the internal genes of the virus,such as mutations of V171M,R198K,N375S,and L473V in PB1 protein,mutation of K319N in NP protein,and mutation of G149A in NS protein.In the M2 protein,there is a mutation of S31N that affects the resistance to amantadine and amantadine.The NS protein has the A42S mutation that can promote the viral replication ability.Studies have shown that the homology of the SIV genes of the H1N1 subtype in four different regions varies greatly,and mutations occur at the key amino acid sites of each gene.
Keywords：Swine influenza virusH1N1 subtypeHomologyGenetic evolution
Publication Date：2025-05-15
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：5( 27-31 )