Role of Membrane Rafts in Viral Infection

Abstract

Membrane rafts are small (10-200 nm), heterogeneous, highly dynamic, sterol- and sphingolipid-enriched domains that compartmentalize cellular processes. Many studies have established that membrane rafts play an important role in the process of virus infection cycle and virus-associated diseases. It is well known that many viral components or virus receptors are concentrated in the lipid microdomains. Viruses are divided into four main classes, nonenveloped RNA virus, enveloped RNA virus, nonenveloped DNA virus, and enveloped DNA virus. General virus infection cycle is also classified into two sections, the early stage (entry) and the late stage (assembly and budding of virion). Caveola-dependent endocytosis has been investigated mostly by analysis of cell entry of the SV40 representative of polyomaviruses. Thus, the study of membrane rafts has been partially advanced by virological researches. Membrane rafts also act as a scaffold of many cellular signal transductions. Involvement of membrane rafts in many virus-associated diseases is often responsible for up- or down-regulation of cellular signal transductions. What is the role of membrane rafts in virus replications? Viruses do not necessarily require and probably utilize membrane rafts for more efficiency in virus entry, viral genome replication, high-infective virion production, and cellular signaling activation toward advantageous virus replication. In this review, we described the involvement of membrane rafts in the virus life cycle and virus-associated diseases.