Column X enlists some of the common animal viruses and column Y enlists cell surface proteins that serve as their receptors. Column X Column Y A. Hepatitis A virus i. Immunoglobulin superfamily B. Rotavirus ii. Acetylcholine receptor on neurons C. Polio virus iii. Alpha 2-macroglobulin D. Rabies virus iv. Acetylated sialic acid on glycoprotein Which one of the following option represent the correct match between column X and Y?
A - iii; B - iv; C - i; D - ii
Animal Virus Receptors: Understanding Viral Entry
Viruses are obligate intracellular parasites, meaning they must enter host cells to replicate. A crucial step in this entry process is the binding of the virus to specific molecules on the surface of the host cell. These molecules are known as cell surface receptors. Different viruses often bind to different receptors, which helps determine which cell types or tissues a virus can infect. This question asks us to match several common animal viruses with the cell surface proteins that serve as their receptors.
Let's look at the provided lists:
Column X (Animal Virus)
- A. Hepatitis A virus
- B. Rotavirus
- C. Polio virus
- D. Rabies virus
Column Y (Cell Surface Protein Receptors)
- Immunoglobulin superfamily
- Acetylcholine receptor on neurons
- Alpha 2-macroglobulin
- Acetylated sialic acid on glycoprotein
We need to find the correct pairing of viruses from Column X with their receptors from Column Y.
Matching Viruses with Receptors
Based on scientific understanding of how these viruses infect cells, we can determine the typical receptors they use:
- Polio virus: The primary receptor for Polio virus (an enterovirus) is the Poliovirus Receptor (PVR), also known as CD155. PVR is a member of the Immunoglobulin superfamily of proteins. Therefore, Polio virus (C) matches with Immunoglobulin superfamily (i).
- Rabies virus: Rabies virus is a neurotropic virus, meaning it infects neurons. It primarily enters cells by binding to the Acetylcholine receptor on neurons, although other receptors like NCAM (Neural Cell Adhesion Molecule) can also be involved. Therefore, Rabies virus (D) matches with Acetylcholine receptor on neurons (ii).
- Rotavirus: Rotaviruses are major causes of diarrheal disease. They interact with various cell surface molecules, including glycans containing sialic acid and glycoproteins. Some strains bind to acetylated sialic acid. Therefore, Rotavirus (B) matches with Acetylated sialic acid on glycoprotein (iv).
- Hepatitis A virus: Hepatitis A virus (HAV) primarily infects liver cells. While the HAV cellular receptor 1 (HAVCR1, also known as TIM-1), which is part of the T cell immunoglobulin and mucin domain family, is a well-known receptor, other interactions may occur. Based on the provided match, Hepatitis A virus (A) matches with Alpha 2-macroglobulin (iii).
Putting these matches together:
- A. Hepatitis A virus → iii. Alpha 2-macroglobulin
- B. Rotavirus → iv. Acetylated sialic acid on glycoprotein
- C. Polio virus → i. Immunoglobulin superfamily
- D. Rabies virus → ii. Acetylcholine receptor on neurons
This gives us the combination A - iii; B - iv; C - i; D - ii.
Summary of Matches
| Column X (Virus) | Column Y (Receptor) |
|---|---|
| Hepatitis A virus | Alpha 2-macroglobulin |
| Rotavirus | Acetylated sialic acid on glycoprotein |
| Polio virus | Immunoglobulin superfamily |
| Rabies virus | Acetylcholine receptor on neurons |
This matches the structure A - iii; B - iv; C - i; D - ii.
Important Questions from Cellular communication
In a neuron, proteins and membranes are primarily synthesized in the cell body. These materials must be transported down the axon to the synaptic region using microtubules in an anterograde fashion. Such axonal transport is directed by
Acetylcholine is a potent neurotransmitter, which is released from the neurons. After release they diffuse across the synaptic cleft and combine with nicotinic acetylcholine receptor molecules in the membrane of the postsynaptic cell. The interaction of acetylcholine with the nicotinic acetylcholine receptor produces large transient increase in the permeability of the membrane to specialized ions resulting in signal transduction for nerve impulse. Acetylcholine receptor is a
Column X represents the type of junctions and column Y represents the proteins associated with the junctions.
Column X
Column Y
A.
Anchoring junction
i.
Claudins
B.
Occluding junction
ii.
Delta-Notch
C.
Channel-forming junction
iii.
Desmoglein
D.
Signal-relaying junction
iv.
Connexin
Which one of the following options is a correct match between terms of Columns X and Y?
Bacteria employ various mechanisms to invade or enter host cells, which are either phagocytic or non-phagocytic in nature. Given below are some of the mechanisms which are generally used for carrying out this process.
A. Some bacteria express a protein called invasin that is recognized by host-cell β1 integrins.
B. Actin polymerization along with assembly of clathrin coat results in the internalization of bacteria by zipper mechanism.
C. Some bacteria, including Salmonella enterica, use trigger mechanism to inject a set of effector molecules in the cytosol through type III secretion system.
D. Some bacteria attach to host cell surface receptors inducing local elevation of Ca2+ in cell cytosol, leading to the fusion of lysosomes with bacteria containing plasma membrane vesicles.
Which one of the following represents the combination of correct mechanisms for invading non-phagocytic cells?
In C. elegans, PAR proteins segregate at the cell cortex in the zygote to establish cell polarity. This is dependent on the regulation of the cortical actin cytoskeleton by RhoA. An investigator sought to directly inhibit actin polymerization to analyze the impact of this inhibition on PAR protein localization. Which one of the following chemicals would be the most suitable?
