scholarly journals The role of Ran-binding protein 3 during influenza A virus replication

2013 ◽  
Vol 94 (5) ◽  
pp. 977-984 ◽  
Author(s):  
Rey Predicala ◽  
Yan Zhou
Keyword(s):  
Life Cycle ◽  
Influenza A Virus ◽  
Nuclear Export ◽  
Influenza A ◽  
Binding Protein ◽  
Late Phase ◽  
Nuclear Retention ◽  
Interacting Protein ◽  
Virus Life Cycle

Influenza A virus vRNP nuclear export is CRM1-dependent. Ran-binding protein 3 (RanBP3) is a Ran-interacting protein that is best known for its role as a cofactor of CRM1-mediated cargo nuclear export. In this study, we investigated the role of RanBP3 during the influenza A virus life cycle. We found that RanBP3 was phosphorylated at Ser58 in the early and late phases of infection. Knockdown of RanBP3 expression led to vRNP nuclear retention, suggesting that RanBP3 is involved in vRNP nuclear export. Moreover, we demonstrated that the function of RanBP3 during vRNP nuclear export is regulated by phosphorylation at Ser58, and that RanBP3 phosphorylation is modulated by both PI3K/Akt and Ras/ERK/RSK pathways in the late phase of viral infection.

scholarly journals Phosphorylation Controls the Nuclear-Cytoplasmic Shuttling of Influenza A Virus Nucleoprotein

2015 ◽  
Vol 89 (11) ◽  
pp. 5822-5834 ◽  
Author(s):  
Weinan Zheng ◽  
Jing Li ◽  
Shanshan Wang ◽  
Shuaishuai Cao ◽  
Jingwen Jiang ◽  
...  
Keyword(s):  
Life Cycle ◽  
Influenza A Virus ◽  
Influenza A ◽  
Early Stage ◽  
Phosphorylation Sites ◽  
Nuclear Retention ◽  
Virus Growth ◽  
Virus Life Cycle ◽  
Importin Α ◽  
Infected Cells

ABSTRACTThe nucleoprotein (NP) is a major component of the viral ribonucleoprotein (vRNP) complex. During the replication of influenza virus, the vRNP complex undergoes nuclear-cytoplasmic shuttling, during which NP serves as one of the determinants. To date, many phosphorylation sites on NP have been identified, but the biological functions of many of these phosphorylation sites remain unknown. In the present study, the functions of the phosphorylation sites S9, Y10, and Y296 were characterized. These residues are highly conserved, and their phosphorylation was essential for virus growth in cell culture and in a mouse model by regulating the activity of the viral polymerase and the nuclear-cytoplasmic shuttling of NP. The phosphorylation and dephosphorylation of S9 and Y10 controlled nuclear import of NP by affecting the binding affinity between NP and different isoforms of importin-α. In addition, the phosphorylation of Y296 caused nuclear retention of NP by reducing the interaction between NP and CRM1. Furthermore, tyrosine phosphorylation of NP during the early stage of virus infection was ablated when Y296 was mutated to F. However, at later stages of infection, it was weakened by the Y10F mutation. Taken together, the present data indicate that the phosphorylation and dephosphorylation of NP control the shuttling of NP between the nucleus and the cytoplasm during virus replication.IMPORTANCEIt is well known that phosphorylation regulates the functions of viral proteins and the life cycle of influenza A virus. As NP is the most abundant protein in the vRNP complex of influenza A virus, several phosphorylation sites on this protein have been identified. However, the functions of these phosphorylation sites were unknown. The present study demonstrates that the phosphorylation status of these sites on NP can mediate its nuclear-cytoplasmic shuttling, which drives the trafficking of vRNP complexes in infected cells. The present data suggest that the phosphorylated residues of NP are multistep controllers of the virus life cycle and new targets for the design of anti-influenza drugs.

scholarly journals Interaction of Nuclear Export Protein with G Protein Pathway Suppressor 2 (GPS2) Facilitates Influenza A Virus Replication by Weakening the Inhibition of GPS2 to RNA Synthesis and Ribonucleoprotein Assembly

2021 ◽  
Vol 95 (10) ◽  
Author(s):  
Wenxiao Gong ◽  
Xinglin He ◽  
Kun Huang ◽  
Yufei Zhang ◽  
Chengfei Li ◽  
...  
Keyword(s):  
Life Cycle ◽  
G Protein ◽  
Influenza A Virus ◽  
Virus Replication ◽  
Nuclear Export ◽  
Influenza A ◽  
Rna Synthesis ◽  
Polymerase Activity ◽  
Nuclear Export Protein ◽  
Export Protein

ABSTRACT The nuclear export protein (NEP) serves multiple functions in the life cycle of influenza A virus (IAV). Identifying novel host proteins that interact with NEP and understanding their functions in IAV replication are of great interest. In this study, we screened and confirmed the direct interaction of G protein pathway suppressor 2 (GPS2) with NEP through a yeast two-hybrid screening assay and glutathione S-transferase pulldown and coimmunoprecipitation assays. Knockdown or knockout of GPS2 enhanced IAV titers, whereas overexpression of GPS2 impaired IAV replication, demonstrating that GPS2 acted as a negative host factor in IAV replication. Meanwhile, GPS2 inhibited viral RNA synthesis by reducing the assembly of IAV polymerase. Interestingly, IAV NEP interacted with GPS2 and mediated its nuclear export, thereby activating the degradation of GPS2. Thus, NEP-GPS2 interaction weakened the inhibition of GPS2 to viral polymerase activity and benefited virus replication. Overall, this study identified the novel NEP-binding host partner GPS2 as a critical host factor to participate in IAV replication. These findings provided novel insights into the interactions between IAV and host cells, revealing a new function for GPS2 during IAV replication. IMPORTANCE NEP is proposed to play multiple biologically important roles in the life cycle of IAV, which largely relies on host factors by interaction. Our study demonstrated that GPS2 could reduce the interaction between polymerase basic 1 (PB1) and PB2 and interfere with viral ribonucleoprotein (vRNP) assembly. Thus, GPS2 inhibited the RNA synthesis of IAV and negatively regulated its replication. Importantly, IAV NEP interacted with GPS2 and mediated the nuclear export of GPS2, thereby activating the degradation of GPS2. Thus, NEP-GPS2 interaction weakened the inhibition of GPS2 to viral polymerase activity and benefited virus replication.

NF90 is a novel influenza A virus NS1-interacting protein that antagonizes the inhibitory role of NS1 on PKR phosphorylation

FEBS Letters ◽  
2016 ◽  
Vol 590 (16) ◽  
pp. 2797-2810 ◽  
Author(s):  
Ting Li ◽  
Xi Li ◽  
WenFei Zhu ◽  
HuiYu Wang ◽  
Lin Mei ◽  
...  
Keyword(s):  
Influenza A Virus ◽  
Influenza A ◽  
Interacting Protein ◽  
Inhibitory Role ◽  
Novel Influenza A

scholarly journals The Functional Role of Loops and Flanking Sequences of G-Quadruplex Aptamer to the Hemagglutinin of Influenza a Virus

2021 ◽  
Vol 22 (5) ◽  
pp. 2409
Author(s):  
Anastasia A. Bizyaeva ◽  
Dmitry A. Bunin ◽  
Valeria L. Moiseenko ◽  
Alexandra S. Gambaryan ◽  
Sonja Balk ◽  
...  
Keyword(s):  
Influenza A Virus ◽  
Influenza A ◽  
Core Structure ◽  
Dna Aptamer ◽  
Tertiary Structures ◽  
Quadruplex Dna ◽  
G Quadruplex ◽  
Flanking Sequences ◽  
Related Proteins

Nucleic acid aptamers are generally accepted as promising elements for the specific and high-affinity binding of various biomolecules. It has been shown for a number of aptamers that the complexes with several related proteins may possess a similar affinity. An outstanding example is the G-quadruplex DNA aptamer RHA0385, which binds to the hemagglutinins of various influenza A virus strains. These hemagglutinins have homologous tertiary structures but moderate-to-low amino acid sequence identities. Here, the experiment was inverted, targeting the same protein using a set of related, parallel G-quadruplexes. The 5′- and 3′-flanking sequences of RHA0385 were truncated to yield parallel G-quadruplex with three propeller loops that were 7, 1, and 1 nucleotides in length. Next, a set of minimal, parallel G-quadruplexes with three single-nucleotide loops was tested. These G-quadruplexes were characterized both structurally and functionally. All parallel G-quadruplexes had affinities for both recombinant hemagglutinin and influenza virions. In summary, the parallel G-quadruplex represents a minimal core structure with functional activity that binds influenza A hemagglutinin. The flanking sequences and loops represent additional features that can be used to modulate the affinity. Thus, the RHA0385–hemagglutinin complex serves as an excellent example of the hypothesis of a core structure that is decorated with additional recognizing elements capable of improving the binding properties of the aptamer.

Sign in / Sign up

Export Citation Format

Share Document