Zebrafish prmt3 negatively regulates antiviral responses

Area of Science:

• Biochemistry
• Immunology
• Molecular Biology

Background:

• Arginine methylation is a crucial post-translational modification regulating protein function.
• Protein arginine methyltransferase 3 (PRMT3) is involved in methylation, but its role in antiviral immunity is unknown.

Purpose of the Study:

• To investigate the role of PRMT3 in the innate immune response to viral infections in zebrafish.

Main Methods:

• Zebrafish models were used to study PRMT3 expression and function during viral infections.
• PRMT3 inhibitors (SGC707) and PRMT3-null zebrafish were employed.
• Interactions with key antiviral signaling molecules like IRF3 and RIG-I were analyzed.

Main Results:

• Zebrafish prmt3 expression increased upon viral infection.
• Overexpression of prmt3 suppressed antiviral responses, while its inhibition or absence enhanced resistance to viruses (SVCV, GCRV).
• PRMT3 negatively impacted IRF3 phosphorylation and interacted with RIG-I, with both zinc-finger and catalytic domains being essential for its suppressive function on IFN activation.

Conclusions:

• Zebrafish PRMT3 acts as a negative regulator of the antiviral innate immune response.
• PRMT3 and potentially arginine methylation play a significant role in modulating antiviral immunity.