CSIR-CCMB scientists uncover key protein that helps cells detect and fight viruses

CSIR-Centre for Cellular and Molecular Biology (CSIR-CCMB) scientists have uncovered a crucial mechanism that helps human cells detect viral infections and launch a rapid immune response, a discovery that could open new avenues for developing broad-spectrum antiviral therapies.

The study, led by Dr. Santosh Chauhan's team at the Hyderabad-based research institute and published in The EMBO Journal, identifies a protein called 'DZIP3' as a key player in the body's first line of defence against viruses.

When viruses invade human cells, they release genetic material that must be detected quickly before the infection spreads. Researchers found that DZIP3 acts both as a sensor that detects viral RNA and as an activator that switches on the immune system's response.

The DZIP3 remains inactive until it encounters viral RNA inside a cell and once it detects the viral genetic material, the protein undergoes a structural change that activates it. The activated protein then moves to the mitochondria, often described as the cell's energy-producing units, where it triggers a chain of events that activates major antiviral defence proteins.

This process leads to the production of Type I interferons - powerful signalling molecules that help prevent viruses from multiplying and spreading. The findings confirm a hypothesis proposed by Dr. Chauhan's laboratory nearly seven years ago that certain human proteins might play a dual role by both sensing viral genetic material and rapidly alerting the immune system.

Researchers demonstrated that the newly identified pathway offers protection against several disease-causing viruses, including SARS-CoV-2, Chikungunya virus, and Japanese Encephalitis virus, highlighting its broad antiviral potential.

"Discovering how DZIP3 senses viral RNA and directly triggers the cell's immune machinery gives us a deeper understanding of human immunity," said Senior Principal Scientist at CSIR-CCMB and lead author of the study Dr. Santosh Chauhan.

The team is now working on developing small-molecule drug candidates designed to enhance DZIP3 activity, with the goal of boosting the body's natural antiviral defences. Such approaches could eventually lead to broad-spectrum treatments against emerging viral threats.

The research was funded by the Department of Biotechnology (DBT). Dr. Rinku Sahu was the study's first author, with contributions from national and international collaborators, said a press release on Thursday.