INVESTIGATION OF THE RELATIONSHIP BETWEEN HUMAN SNX-2 PROTEIN AND INFLUENZA VIRUS RNA POLYMERASE ENZYME IN MAMMALIAN CELLS

Uluslararası Gevher Nesibe Sağlık Bilimleri Kongresi, Ankara, Turkey, 23 - 24 November 2019, pp.124, (Summary Text)

Influenza A viruses are the viral pathogens that cause common upper respiratory diseases in

human. These viruses change their genetic characteristics at high frequencies, which leads to

the emergence of new virus types, prevent vaccine protection and resistant to existing drugs.

Therefore, alternative strategies should be developed to cope with influenza A viruses. In this

context, the elucidation of the relationship between influenza A virus and the host cell at the

molecular level will be a guide in dealing with the viruses. It has been shown interaction

between human sorting nexin-2 (SNX-2) protein and influenza virus RNA polymerase subunit

PA by using yeast two hybrid method in our different project (TUBITAK, grant number:

112S518). In this work it was aimed to reveal the relationship between influenza PA and the

SNX-2 protein in human cells, and to demonstrate the importance of SNX-2 protein in terms of

influenza virus replication. For this purpose, HeLa and HEK293 cells originated from human

were utilized. The physical interaction between viral PA protein and human SNX-2, which

temporarily synthesized in the cells by plasmid transfection, was investigated by

immunoprecipitation and immunofluorescence methods. The endogenous SNX-2 protein level

in the cells was increased with transient transfection or reduced (knock-down) by gene-specific

siRNAs. The replication of influenza A virus were examined in these cells.

Co-immunoprecipitation analyses revealed the interactions between virus PA and SNX-2

protein in HEK293 cells. It was observed that the carboxyl-domains of SNX-2 has interact with

viral PA protein. This result was also supported with immunofluorescence assay. Influenza viral

replication was positively affected in SNX-2 knock down cells. In contrast, the over-expression

of SNX-2 in the cells has not shown a significant effect on influenza virus replication. These

results suggest that SNX-2 have a negative regulatory effect on influenza virus replication.

SNX-2 has a function in the vesicular trafficking. From this perspective, the question of how

SNX-2 protein influences the influenza virus replication still remains to be answered.

Keywords: Influenza, viral RNA polymerase, PA protein, SNX-2 protein

*This work was supported by a grant from the scientific research foundation of Marmara

University (grant number: SAG-C-YLP-120619-0224) and a grant from The Scientific and

Technological Research Council of Turkey (grant number: 112S518).