Tree Shrew Genome-Wide CRISPR Screen Identifies RNF6 as a Proviral Host Factor for Zika Virus Replication in Brain...

Area of Science:

• Virology
• Neuroscience
• Genetics

Background:

• Zika virus (ZIKV) poses risks due to its neurotropic and teratogenic potential.
• Mechanisms of ZIKV crossing the blood-brain barrier and infecting brain cells are not fully understood.
• Existing treatments for ZIKV are limited, necessitating the identification of host factors involved in infection.

Purpose of the Study:

• To identify novel host factors that mediate Zika virus infection in human brain microvascular endothelial cells (BMECs).
• To investigate the role of identified host factors in ZIKV replication and pathogenesis.
• To explore potential antiviral strategies targeting host factors.

Main Methods:

• Established the first tree shrew genome-wide CRISPR/Cas9 knockout (GeCKO) library.
• Performed a GeCKO screen in BMECs to identify host factors influencing ZIKV infection.
• Conducted gene knockout, knockdown, and overexpression experiments to validate findings.
• Analyzed protein-protein interactions, signaling pathways (type I interferon, MAPK), evolutionary conservation, and molecular docking.

Main Results:

• Identified ring finger protein 6 (RNF6) as a proviral factor for ZIKV.
• RNF6 knockout/knockdown reduced ZIKV infection, while overexpression enhanced it.
• RNF6 interacts with ZIKV NS5 protein and negatively regulates type I interferon and MAPK pathways.
• RNF6 is highly conserved between humans and tree shrews, with shared NS5-binding residues.

Conclusions:

• Tree shrew GeCKO screening is an effective method for discovering host factors in viral infections.
• RNF6 is a critical proviral factor for ZIKV replication in BMECs.
• RNF6 presents a potential target for developing antiviral strategies against ZIKV neuroinvasion.