Regulation of Yamanaka factors during H5N1 virus infection in A549 cells and HEK293T cells

Abstract

Avain influenza (AI) virus H5N1 poses a serious threat to public health. Yamanaka factors (Oct4, Sox2, Klf4, c-Myc) are usually transcription factors involved in proliferation, apoptosis, differentiation, immunity and somatic cell reprogramming. However, the expression status of Yamanaka factors related to influenza virus infection has not yet been described. Here our results showed that SOX2, MYC and KLF4 were significantly overexpressed in HEK293T cells as compared to A549 cells. The H5N1 virus infection experiment showed that OCT4 and KLF4 were up-regulated and MYC was down-regulated during high titer virus infection in A549 cells. In HEK293T cells, OCT4, SOX2 and KLF4 were up-regulated and MYC was down-regulated by H5N1 infection. Overexpression of NP and PB2 of H5N1 virus induced up-regulation of OCT4 in A549 cells. In addition, KF4 was increased only by overexpression of NP protein in A549 cells. However, KLF4 was down-regulated by overexpression of PB2 protein in HEK293T cells. Yamanaka factors were not found to be significantly affected by NS1 and M1 in A549 and HEK293T cells. HA or NA did not affect the expression of Yamanaka factors in HEK293T cells. In conclusion, the expression patterns of Yamanaka factors during H5N1 infection could be a novel regulatory mechanism involved in the pathogenesis of influenza viruses.