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Updated: Jul 12, 2026
12:20
Bacterial Artificial Chromosomes: A Functional Genomics Tool for the Study of Positive-strand RNA Viruses
Published on: December 29, 2015
Distinct RNA engagements define genome import and replication elongation in alphaviruses
Yaw Bia Tan1,2, Yongbo Luo1,2, Ping Liu1,2
1Lee Kong Chian School of Medicine, Nanyang Technological University, 59 Nanyang Drive, Singapore 636921.
Biorxiv : the Preprint Server for Biology
|July 10, 2026
Summary
This study reveals how Chikungunya virus RNA enters replication complexes using cryo-electron microscopy. It shows distinct RNA binding sites coordinating RNA delivery and synthesis for viral replication.
Area of Science:
- Virology
- Structural Biology
- Molecular Biology
Background:
- Alphavirus replication occurs in membrane-associated spherules.
- Mechanisms of viral RNA delivery and synthesis coordination are unclear.
Purpose of the Study:
- To elucidate the structural basis of RNA trafficking and synthesis coordination in Chikungunya virus replication complexes.
Main Methods:
- Cryo-electron microscopy (cryo-EM) of the Chikungunya virus replication complex (RC) core.
- Structural analysis of nsP1, nsP2, and nsP4 in complex with RNA substrates.
Main Results:
- Identified two distinct RNA-binding sites within the RC core.
- A single-stranded RNA (ssRNA) binds nsP2 and extends toward an nsP1-nsP4 pore.
- A double-stranded RNA (dsRNA) binds the nsP4 polymerase in an elongation configuration.
- Proposed a helicase-assisted RNA threading model for genome delivery.
Conclusions:
- The RC core integrates genome import and RNA synthesis within a membrane-associated machine.
- Provides a structural framework for understanding alphavirus replication organelle function.
- Highlights potential targets for antiviral therapies.
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