title: Influenza virus A/Beijing/501/2009(H1N1) NS1 interacts with β-tubulin and induces disruption of the microtubule network and apoptosis on A549 cells.
abstract: NS1 of influenza A virus is a key multifunctional protein that plays various roles in regulating viral replication mechanisms, host innate/adaptive immune responses, and cellular signalling pathways. These functions rely on its ability to participate in a multitude of protein-protein and protein-RNA interactions. To gain further insight into the role of NS1, a tandem affinity purification (TAP) method was utilized to find unknown interaction partner of NS1. The protein complexes of NS1 and its interacting partner were purified from A549 cell using TAP-tagged NS1 as bait, and co-purified cellular factors were identified by mass spectrometry (MS). We identified cellular β-tubulin as a novel interaction partner of NS1. The RNA-binding domain of NS1 interacts with β-tubulin through its RNA-binding domain, as judged by a glutathione S-transferase (GST) pull-down assay with the GST-fused functional domains of NS1. Immunofluorescence analysis further revealed that NS1 with β-tubulin co-localized in the nucleus. In addition, the disruption of the microtubule network and apoptosis were also observed on NS1-transfected A549 cells. Our findings suggest that influenza A virus may utilize its NS1 protein to interact with cellular β-tubulin to further disrupt normal cell division and induce apoptosis. Future work will illustrate whether this interaction is uniquely specific to the 2009 pandemic H1N1 virus.
authors.affiliation: Chinese Academy of Inspection and Quarantine, Beijing, China.
authors.forename: Xueqing
authors.initials: X
authors.lastname: Han
authors.forename: Zhihui
authors.initials: Z
authors.lastname: Li
authors.forename: Hongjun
authors.initials: H
authors.lastname: Chen
authors.forename: Huiyu
authors.initials: H
authors.lastname: Wang
authors.forename: Lin
authors.initials: L
authors.lastname: Mei
authors.forename: Shaoqiang
authors.initials: S
authors.lastname: Wu
authors.forename: Tianyi
authors.initials: T
authors.lastname: Zhang
authors.forename: Bohua
authors.initials: B
authors.lastname: Liu
authors.forename: Xiangmei
authors.initials: X
authors.lastname: Lin
mesh_terms: D000595:Amino Acid Sequence; D017209:Apoptosis; D002467:Cell Nucleus / Q000378:metabolism; D048430:Cell Shape; D006801:Humans; D053118:Influenza A Virus, H1N1 Subtype / Q000378:metabolism*; D008870:Microtubules / Q000378:metabolism*; D008969:Molecular Sequence Data; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D021381:Protein Transport; D014404:Tubulin / Q000737:chemistry / Q000378:metabolism; D017361:Viral Nonstructural Proteins / Q000737:chemistry / Q000378:metabolism*
chemical_list: C085820:INS1 protein, influenza virus; D014404:Tubulin; D017361:Viral Nonstructural Proteins