Related Experiment Video

Updated: Dec 29, 2025

Affinity Purification of Influenza Virus Ribonucleoprotein Complexes from the Chromatin of Infected Cells
11:20

Affinity Purification of Influenza Virus Ribonucleoprotein Complexes from the Chromatin of Infected Cells

Published on: June 3, 2012

13.4K

Influenza A virus protein PB1-F2 impairs innate immunity by inducing mitophagy

Ruifang Wang1,2, Yinxing Zhu1,2, Chenwei Ren1,2

  • 1State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China.

Autophagy
|February 5, 2020
PubMed

Insights

Influenza A virus PB1-F2 protein triggers mitophagy, clearing damaged mitochondria. This process impairs innate immunity by degrading MAVS and suppressing interferon production, presenting a therapeutic target.

Area of Science:

  • Cellular biology
  • Virology
  • Immunology

Background:

  • Influenza A virus (IAV) infection can induce mitophagy, a process crucial for removing damaged mitochondria.
  • The IAV PB1-F2 protein is known to translocate to mitochondria, accelerate fragmentation, and impair innate immunity.
  • The precise mechanisms by which PB1-F2 influences mitophagy and its connection to immune suppression remain unclear.

Purpose of the Study:

  • To investigate whether the IAV PB1-F2 protein mediates IAV-induced mitophagy.
  • To elucidate the relationship between PB1-F2-induced mitophagy and the suppression of innate immunity.
  • To identify the molecular players and motifs involved in PB1-F2-mediated mitophagy.

Main Methods:

  • Co-immunoprecipitation and colocalization assays to study protein interactions.
  • Analysis of mitophagy induction and autophagosome formation.
  • Assessment of mitochondrial antiviral signaling protein (MAVS) degradation and type I interferon production.
  • Site-directed mutagenesis to investigate the role of the LIR motif in PB1-F2.

Main Results:

  • PB1-F2 interacts with and colocalizes to mitochondria with Tu translation elongation factor, mitochondrial (TUFM).
  • PB1-F2 induces complete mitophagy by interacting with TUFM and microtubule associated protein 1 light chain 3 beta (MAP1LC3B), facilitating autophagosome formation.
  • PB1-F2-induced mitophagy leads to MAVS degradation and suppresses type I interferon production.
  • The C-terminal LC3-interacting region (LIR) motif of PB1-F2 is essential for mitophagy induction and innate immune suppression.

Conclusions:

  • The IAV PB1-F2 protein directly induces mitophagy through interactions with TUFM and MAP1LC3B.
  • PB1-F2-mediated mitophagy is a key mechanism for suppressing cellular innate immunity by degrading MAVS and inhibiting interferon production.
  • PB1-F2-induced mitophagy represents a potential therapeutic target for combating influenza A virus infections.
Keywords:
Influenza PB1-F2 proteinLC3bMAVSTUFMinnate immunitymitophagy

More Related Videos

Identifying Caspases and their Motifs that Cleave Proteins During Influenza A Virus Infection08:16

Identifying Caspases and their Motifs that Cleave Proteins During Influenza A Virus Infection

Published on: July 21, 2022

1.8K
Co-immunoprecipitation of the Mouse Mx1 Protein with the Influenza A Virus Nucleoprotein09:39

Co-immunoprecipitation of the Mouse Mx1 Protein with the Influenza A Virus Nucleoprotein

Published on: April 21, 2015

18.2K

Related Concept Videos

Leaky Scanning02:28

Leaky Scanning

During most eukaryotic translation processes, the small 40S ribosome subunit scans an mRNA from its 5' end until it encounters the first start AUG codon. The large 60S ribosomal subunit then joins the smaller one to initiate protein synthesis. The location of the translation initiation is largely determined by the nucleotides near the start codon as there may be multiple translation initiation sites present on the mRNA.  Marilyn Kozak discovered that the sequence RCCAUGG (where R...
5.6K
Immune Response Against Viral Pathogens01:29

Immune Response Against Viral Pathogens

The immune system's response to viral infections is a complex and coordinated process involving natural killer (NK) cells, T cell-mediated responses, and antibody-mediated responses.
NK Cells
NK cells are a crucial part of our innate immune system, acting as the first line of defense against viral infections. These cells can recognize and kill infected cells without prior exposure to the virus, effectively slowing down the spread of infection. Additionally, NK cells produce proinflammatory...
1.6K
The Extrinsic Apoptotic Pathway01:17

The Extrinsic Apoptotic Pathway

The extrinsic apoptotic pathway is initiated when extracellular death-inducing signals, such as specific cytokines, activate the death receptors expressed on the cell surface. The immune cells involved in this pathway are natural killer cells (NK cells) and cytotoxic T-lymphocytes. NK cells are critical in innate immune response, while cytotoxic T-lymphocytes are associated with adaptive immune response. These cells recognize specific receptors expressed on the altered cells and activate...
7.9K
Phagocytosis of Apoptotic Cells01:17

Phagocytosis of Apoptotic Cells

Cells undergoing apoptosis form apoptotic bodies that must be removed immediately to prevent inflammation, autoimmune diseases, and necrosis. Phagocytosis is carried out by professional phagocytes such as macrophages or  immature dendritic cells. Non-professional phagocytes such as  epithelial cells and fibroblasts also take part in this process; however, they are not as effective as professional phagocytes. 
Normal cells contain receptors that prevent them from being recognized...
4.8K
The Intrinsic Apoptotic Pathway01:31

The Intrinsic Apoptotic Pathway

Internal cellular stress, such as cellular injury or hypoxia, triggers intrinsic apoptosis. The B-cell lymphoma 2 (Bcl-2) family of proteins are the primary regulators of the intrinsic apoptotic pathway. For example, during DNA damage, checkpoint proteins, such as Ataxia Telangiectasia Mutated (ATM protein) and Checkpoints Factor-2 (Chk2) proteins, are activated. These proteins phosphorylate p53 which further activates pro-apoptotic proteins, such as Bax, Bak, PUMA, and Noxa, and inhibits...
8.1K