Type I interferons in ray-finned fish (Actinopterygii)

Area of Science:

• Immunology
• Zoology
• Molecular Biology

Background:

• Interferons (IFNs) are vital immune response proteins found across vertebrates.
• Ray-finned fish possess IFN type I and II, but IFN type III presence is unconfirmed.
• Type I IFNs in Actinopterygii are classified into three groups with subgroups.

Purpose of the Study:

• To investigate the antiviral and antimicrobial roles of Interferons (IFNs) in ray-finned fish (Actinopterygii).
• To understand the signaling pathways and gene expression induced by IFNs in fish immune responses.

Main Methods:

• Review of existing literature on IFN types and functions in Actinopterygii.
• Analysis of IFN signaling pathways, including JAK-STAT.
• Examination of IFN-stimulated gene (ISG) expression and IFN-stimulated response elements (ISRE).

Main Results:

• Type I IFNs in Actinopterygii primarily exhibit antiviral activity through the JAK-STAT pathway, inducing ISG expression.
• In Perciformes and Cyprinidae, type I/I interferons also contribute to antimicrobial responses.
• This antimicrobial role involves inducing inducible nitric oxide synthase (iNOS) and influencing reactive oxygen species (ROS) production during phagocytosis.

Conclusions:

• Type I IFNs in ray-finned fish are key players in both antiviral and, in certain groups, antimicrobial immunity.
• The JAK-STAT pathway and ISG induction are central to IFN antiviral functions.
• IFN-mediated antimicrobial activity highlights a broader immune role for these cytokines in fish.