Adenoviruses in Avian Hosts: Recent Discoveries Shed New Light on Adenovirus Diversity and Evolution

Abstract

While adenoviruses cause infections in a wide range of vertebrates, members of the genus Atadenovirus, Siadenovirus, and Aviadenovirus predominantly infect avian hosts. Several recent studies on avian adenoviruses have encouraged us to re-visit previously proposed adenovirus evolutionary concepts. Complete genomes and partial DNA polymerase sequences of avian adenoviruses were extracted from NCBI and analysed using various software. Genomic analyses and constructed phylogenetic trees identified the atadenovirus origin from an Australian native passerine bird in contrast to the previously established reptilian origin. In addition, we demonstrated that the theories on higher AT content in atadenoviruses are no longer accurate and cannot be considered as a species demarcation criterion for the genus Atadenovirus. Phylogenetic reconstruction further emphasised the need to reconsider siadenovirus origin, and we recommend extended studies on avian adenoviruses in wild birds to provide finer evolutionary resolution.

Structural and functional characterization of siadenovirus core protein VII nuclear localization demonstrates the existence of multiple nuclear transport pathways

“…The family Adenoviridae exhibits substantial diversity in genome size and gene content. The recently discovered psittacine siadenovirus F is of particular significance as it causes diseases among the critically endangered Australian parrot, the orange-bellied parrot [1]. There is a pressing need for a better understanding of psittacine adenovirus F to develop therapeutic options.…”

“…Adenoviruses are complex DNA viruses identified in all types of vertebrates causing both clinical and subclinical infections [1][2][3]. Human adenoviruses are the most extensively studied and are usually associated with respiratory, gastrointestinal and ocular infections [2]; the next most studied adenoviruses are from domestic and wild avian species [1,4].…”

“…Adenoviruses are complex DNA viruses identified in all types of vertebrates causing both clinical and subclinical infections [1][2][3]. Human adenoviruses are the most extensively studied and are usually associated with respiratory, gastrointestinal and ocular infections [2]; the next most studied adenoviruses are from domestic and wild avian species [1,4]. The capsid structure of adenoviruses comprises three primary capsid proteins, namely hexon, penton and fibre, along with several major and minor core proteins that aid in assembling and maintaining the viral core [2,3].…”

Emerging and Novel Viruses in Passerine Birds

“…In addition, results suggest a broad variety of adenoviruses circulating in passerines [ 58 ]. A complete adenovirus genome was recovered from the eastern spinebill ( Acanthorhynchus tenuirostris ), and proposed as a new viral species Passerine adenovirus 1 (PaAdV-1) [ 62 ]. It is highly divergent from previously known taxa, with Atadenovirus genomic organization, the highest sequence similarity (55.6%) to psittacine atadenovirus-3 (PsAdV-3), but 17 predicted novel genes.…”

Noninvasive Surveillance and Evolutionary Insight into Siadenovirus among Antarctic Penguins

“…Adenoviruses are double-stranded nonenveloped, DNA viruses with a linear genome of approximately 25-45 kb [1,2]. Adenoviruses have a similar structural morphology, but the terminal region of the genome differs between viruses of different genera [3]. Adenovirus virions contain three major capsid proteins, hexon (II), penton base (III), and fiber (IV); four minor proteins (IIIa, VI, VIII, and IX); and six other proteins (V, VII, μ, IVa2, terminal protein, and protease) [4].…”