Mayaro Virus Non-Structural Protein 2 Circumvents the Induction of Interferon in Part by Depleting Host Transcription...

Area of Science:

• Virology
• Immunology
• Molecular Biology

Background:

• Mayaro virus (MAYV) is an emerging alphavirus causing debilitating arthralgia and myalgia in humans.
• MAYV has pandemic potential due to its ability to adapt to urban environments.
• The interferon (IFN) system is crucial for antiviral defense against RNA viruses like alphaviruses.

Purpose of the Study:

• To investigate how MAYV infection impacts the induction phase of the IFN response.
• To identify the viral mechanisms responsible for suppressing IFN production during MAYV infection.

Main Methods:

• Investigated IFN-α/β and IFN-λ production during MAYV infection.
• Mapped the viral protein responsible for IFN suppression using expression studies.
• Utilized interactome analysis to identify host protein interactions with viral proteins.
• Quantified host protein levels during viral infection.

Main Results:

• MAYV infection efficiently suppressed the production of type I and III IFNs.
• The viral non-structural protein 2 (nsP2) was identified as sufficient for suppressing IFN production.
• nsP2 was found to interact with host transcription factors Rpb1 and TFIIE2.
• nsP2 expression and MAYV infection reduced levels of Rpb1 and TFIIE2, inhibiting host cell transcription.

Conclusions:

• MAYV nsP2 inhibits the host IFN response by targeting key transcription machinery.
• nsP2-mediated inhibition of host cell transcription is a key mechanism for alphavirus immune evasion.
• Understanding these mechanisms can aid in developing vaccines and antivirals against MAYV and other alphaviruses.