RNA viruses infect cells by introducing their viral RNA into the cell's cytoplasm. This viral RNA then acts as a template to be translated into viral proteins, which are crucial for the virus's replication.
Steps of RNA Virus Infection
Here's a simplified breakdown of the infection process:
- Entry: The RNA virus first gains entry into a host cell.
- RNA Release: Once inside, the virus releases its RNA into the cell's cytoplasm.
- Translation: The cell's machinery reads the viral RNA and translates it into viral proteins. These proteins are essential for the virus to replicate itself.
- Replication: Using the newly made viral proteins, the virus replicates its RNA and assembles new viral particles.
- Release: Finally, the newly formed virus particles are released from the cell to infect other cells.
Defense Mechanisms
Human cells aren't defenseless against RNA viruses.
- RIG-I-like Receptors (RLRs): As stated in the reference, cells use cytoplasmic RIG-I-like receptors as a first line of defense. These receptors can detect viral RNA in the cytoplasm.
- Immune Response: When RLRs detect viral RNA, they trigger an immune response aimed at fighting off the virus.
Summary Table
| Stage | Description |
|---|---|
| Viral Entry | The virus enters the host cell. |
| RNA Release | Viral RNA is released into the cell's cytoplasm. |
| Translation | Cell's machinery translates viral RNA into proteins. |
| Replication | Viral proteins help replicate RNA and assemble new viral particles. |
| Release | Newly formed viruses exit the cell to infect others. |
| Host Defense | RLRs recognize the viral RNA and initiate an immune response. |
In essence, RNA viruses hijack the host cell's machinery to replicate themselves by directly introducing their RNA into the cell's cytoplasm. This direct access bypasses many steps that DNA viruses would need, but the cell has its own defense mechanisms to counter the infection.
