Abstract
Interferons (IFNs) play crucial roles in host defense against viral infections by inducing the expression of numerous IFN-stimulated genes (ISGs) that can activate host antiviral immunity. Interferon-inducible transmembrane proteins (IFITMs), a family of small transmembrane proteins, are critical ISG products. Compelling evidence has implicated that IFITMs can establish an innate immune state to eliminate pathogens efficiently. IFITM proteins can impede broad-spectrum viral infection through various mechanisms. It is generally believed that IFITMs can block the viral entry by suppressing viral membrane fusion. However, some findings indicated that IFITMs might also inhibit viral gene expression and viral protein synthesis and thereby impair viral replication. IFITMs may incorporate into virions during viral assembly and thus reduce the infectivity of nascent virions. The precise inhibitory mechanism of IFITMs on viral infection and replication still requires further exploration. In this review, we highlight the recent findings regarding critical roles of IFITMs in host-virus interaction. We also discuss the molecular mechanisms underlying their functions in antiviral responses.
Highlights
In recent years, extensive studies have explored the innate defense mechanisms and cellular proteins involved in immunity against the infection of pathogens (Ishikawa and Barber, 2008; Unterholzner et al, 2010; Maarouf et al, 2018)
It is well-known that IFN-stimulated genes (ISGs) are critical for innate immunity against infection caused by human immunodeficiency virus (HIV-1), influenza A virus (IAV), West Nile virus (WNV), dengue virus (DENV), etc (Brass et al, 2009; Schoggins and Rice, 2011)
Interferoninducible transmembrane proteins (IFITMs) have been identified as key ISGs that interfere with viral endosomal membrane fusion and the infectivity of nascent virions (Brass et al, 2009; Huang et al, 2011; Lu et al, 2011)
Summary
Extensive studies have explored the innate defense mechanisms and cellular proteins involved in immunity against the infection of pathogens (Ishikawa and Barber, 2008; Unterholzner et al, 2010; Maarouf et al, 2018). The innate immune responses include induction of type I and type III interferons (IFNs) and subsequent expression of interferonstimulating genes (ISGs) (Pulit-Penaloza et al, 2012; Wei et al, 2014). These ISGs encode specific proteins with distinct antiviral functions such as inhibitions of viral entry, viral gene transcription, viral protein synthesis, and viral particle assembly and release (Smith et al, 2014; Kane et al, 2016; Rabbani et al, 2016). We summarized the biological characteristics of IFITM genes, the antiviral properties of IFITM proteins, and their antiviral mechanisms
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
