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Related Experiment Video

Updated: Dec 16, 2025

Harvesting Venom Toxins from Assassin Bugs and Other Heteropteran Insects

Harvesting Venom Toxins from Assassin Bugs and Other Heteropteran Insects

Published on: April 21, 2018

Viperin Reveals Its True Function.

Efraín E Rivera-Serrano¹, Anthony S Gizzi^2,3, Jamie J Arnold¹

¹Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA;

Annual Review of Virology

|July 1, 2020

Summary

This summary is machine-generated.

Viperin, an antiviral restriction factor, converts cytidine triphosphate (CTP) into a molecule that stops viral RNA synthesis. This enzymatic activity provides a direct antiviral mechanism against various viruses.

Keywords:

RNA-dependent RNA polymerase RSAD2 chain terminator interferon radical SAM protein viperin

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Last Updated: Dec 16, 2025

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Area of Science:

Immunology
Virology
Biochemistry

Background:

Cells activate innate immune pathways and antiviral restriction factors during viral infections.
Viperin, identified nearly 20 years ago, exhibits broad antiviral activity through various proposed mechanisms.

Purpose of the Study:

To review the diverse antiviral mechanisms and biological functions of viperin.
To highlight the enzymatic activity of viperin in producing a novel ribonucleotide.

Main Methods:

Literature review of studies on viperin's antiviral functions.
Biochemical analysis of viperin's enzymatic activity.

Main Results:

Viperin catalyzes the conversion of CTP to 3'-deoxy-3',4'-didehydro-CTP (ddhCTP).
Incorporation of ddhCTP into viral RNA leads to premature termination of RNA synthesis.
This enzymatic function is the only known viperin activity directly linked to an antiviral mechanism in human cells.

Conclusions:

Viperin possesses a unique enzymatic mechanism for inhibiting viral replication.
Understanding viperin's functions is crucial for developing novel antiviral strategies.