Receptor Binding

Definition

Receptor binding refers to the specific interaction between a virus and a host cell's surface receptors, which is crucial for the virus to enter the cell. This interaction determines the virus's host range, tissue tropism, and overall infectivity. The ability of a virus to bind to its target receptors directly influences how effectively it can infect host cells and spread within the organism.

5 Must Know Facts For Your Next Test

1. Different viruses have evolved various strategies for receptor binding, which can include using glycoproteins or other viral surface structures.
2. Receptor binding can be a key determinant in the species specificity of a virus; some viruses can only infect specific hosts due to the absence of compatible receptors.
3. The binding affinity between a virus and its receptor can influence the efficiency of viral entry into host cells and subsequent infection.
4. Receptor binding is often the first step in viral entry mechanisms, leading to processes like membrane fusion or endocytosis.
5. Mutations in either viral proteins or host cell receptors can alter receptor binding, potentially leading to changes in virulence or the emergence of new viral strains.

Review Questions

• How does receptor binding influence the infectivity of a virus?
  • Receptor binding is crucial for determining how effectively a virus can attach to and enter a host cell. The specificity and affinity of this interaction dictate whether a virus can infect certain cells or tissues. If a virus cannot bind well to its target receptors, it will struggle to establish an infection, limiting its ability to spread within the host.
• What role do attachment proteins play in receptor binding and how can they affect viral tropism?
  • Attachment proteins are essential components of viruses that facilitate the initial contact with host cell receptors during receptor binding. These proteins are specifically adapted to recognize and bind to particular receptors on target cells, which affects the virus's ability to infect those cells. Variations in attachment proteins can lead to different viral tropisms, as they determine which cells or tissues a virus can successfully infect.
• Evaluate the implications of receptor binding mutations on viral evolution and public health.
  • Mutations in receptor binding sites can significantly impact viral evolution by allowing pathogens to adapt to new hosts or escape immune responses. Such changes can enhance virulence or enable zoonotic transmissions, where viruses jump from animals to humans. This has serious implications for public health, as new strains with altered receptor binding capabilities may lead to outbreaks of diseases that were previously contained or less severe, necessitating ongoing surveillance and vaccine development efforts.

Related terms

Attachment Proteins: Molecules on the surface of viruses that mediate the initial contact and binding to host cell receptors.

Tropism:

The preference of a virus to infect specific cell types or tissues based on receptor availability.

Endocytosis: The process by which cells internalize molecules, including viruses, after receptor binding.