Fundamental Characteristics of Bat Interferon Systems

Abstract

Interferons are an essential component of the innate arm of the immune system and are arguably one of the most important lines of defence against viruses. The human IFN system and its functionality has already been largely characterized and studied in detail. However, the IFN systems of bats have only been marginally examined to date up until the recent developments of the Bat1k project which have now opened new opportunities in research by identifying six new bat genomes to possess novel genes that are likely associated with viral tolerance exhibited in bats. Interestingly, bats have been hypothesized to possess the ability to establish a host-virus relationship where despite being infected, they exhibit limited signs of disease and still retain the ability to transmit the disease into other susceptible hosts. Bats are one of the most abundant and widespread vertebrates on the planet and host many zoonotic viruses that are highly pathogenic to humans. Several genomics, immunological, and biological features are thought to underlie novel antiviral mechanisms of bats. This review aims to explore the bat IFN system and developments in its diverse IFN features, focusing mainly on the model species, the Australian black flying fox (Pteropus alecto), while also highlighting bat innate immunity as an exciting and fruitful area of research to understand their ability to control viral-mediated pathogenesis.

Bat Employs a Conserved MDA5 Gene to Trigger Antiviral Innate Immune Responses

“…Bats are one of the most abundant and geographically distributed vertebrates on earth. There are more than 1,300 species of bats, and they are considered to be the second most ancient mammal species after rodents ( 1 , 2 ). Bats are hosts of zoonotic viruses such as rabies, Hendra and Nipah, which are highly pathogenic to humans.…”

Positively selected genes in the hoary bat (Lasiurus cinereus) lineage: prominence of thymus expression, immune and metabolic function, and regions of ancient synteny

“…While gene duplication is a common evolutionary occurrence, the potential for alternative regulation of STING via a Steep1 paralog is of particular interest given that STING is a powerful mediator of innate immunity, particularly to viruses ( Clayton & Munir, 2020 ), and one that has evolved dampened activity in bats ( Xie et al, 2018 ). Indeed, human symptoms associated with infection by the coronavirus SARS-CoV-2 have been characterized as a detrimental STING response ( Berthelot & Lioté, 2020 ).…”

In Silico Characterization of Human Interferon Alpha/Beta Receptor 2 (Isoform A, B and C) Protein

“…These results were also supported by the presence of transmembrane alpha helical regions. Structural characteristics and cellular localization are important features for INFs bindingand respective downstream signalling for various functions, 16 particularly cell proliferation, signal transduction, immune system processing, 17,18 and stress responses. 12 Our study is limited to the in silico analysis and need wet lab confirmation, but results of this analysis will be helpful in future, to understand the 3D structural basis for any drug related interactions, 19 of human interferon alpha/ beta receptor 2 isoforms.…”