Coxsackievirus and adenovirus receptor

Coxsackievirus and adenovirus receptor (CAR) is a transmembrane protein that plays a crucial role in viral infection and cellular functions. It is primarily known for its role as a receptor for both coxsackieviruses and adenoviruses, which are significant pathogens in humans, causing a range of diseases from mild respiratory infections to severe conditions such as myocarditis. The understanding of CAR's structure, function, and involvement in viral pathogenesis is crucial for developing targeted therapies and vaccines.

Structure and Function

CAR is a member of the immunoglobulin superfamily and is composed of two extracellular immunoglobulin-like domains, a single transmembrane domain, and a short cytoplasmic tail. The extracellular domain of CAR is responsible for the direct binding with the fiber knob domain of adenoviruses and the capsid proteins of coxsackieviruses, facilitating viral attachment and entry into host cells.

Beyond its role in viral infection, CAR is also involved in various cellular processes, including cell adhesion, migration, and signaling pathways that are crucial for tissue development and homeostasis. CAR is expressed in a wide range of tissues, including the heart, brain, and lungs, reflecting its importance in multiple physiological contexts.

Role in Viral Infection

The interaction between CAR and viruses is a key step in the viral life cycle. For adenoviruses, binding to CAR allows the virus to attach to the surface of host cells, a prerequisite for viral entry and subsequent infection. Similarly, coxsackieviruses utilize CAR to gain entry into host cells, leading to infection and disease manifestation.

The specificity of the interaction between CAR and these viruses has been exploited in the development of adenovirus-based gene therapy vectors. By modifying the adenovirus to reduce its pathogenicity and enhance its specificity for CAR, researchers have created vectors for delivering therapeutic genes to specific tissues.

Clinical Significance

The role of CAR in viral infections makes it a potential target for therapeutic intervention. Inhibiting the interaction between CAR and viruses could prevent viral entry and infection, offering a strategy for treating diseases caused by coxsackieviruses and adenoviruses. Additionally, the involvement of CAR in cell adhesion and signaling pathways suggests that it may play a role in cancer and other diseases where these processes are dysregulated.

Understanding the mechanisms regulating CAR expression and function is also critical for the safe and effective use of adenovirus-based gene therapy vectors. Modulating CAR expression in target tissues can enhance the specificity and efficiency of gene delivery, reducing the risk of off-target effects and improving therapeutic outcomes.

Research Directions

Current research on CAR is focused on elucidating its structure-function relationships, understanding its role in disease, and exploring its potential as a therapeutic target. Studies are also underway to develop CAR-targeting drugs and to optimize adenovirus-based vectors for gene therapy. The ongoing discovery of CAR's functions and interactions offers promising avenues for the development of novel treatments for a variety of diseases.

See Also

• Adenovirus
• Coxsackievirus
• Viral entry
• Gene therapy
• Immunoglobulin superfamily