Genetic characterization of two novel picornaviruses from birds, white-tailed eagle (Haliaeetus albicilla) and pied avocet (Recurvirostra avosetta) in Hungary

TL;DR

Scientists discovered and characterized two new bird-related picornaviruses in Hungary, which may represent new species or genera.

Contribution

Identification and genetic characterization of two novel picornaviruses from birds, suggesting new species or genera in the Picornaviridae family.

Findings

Two novel picornaviruses were detected in white-tailed eagle and pied avocet in Hungary.

The viruses showed moderate amino acid sequence identities to known picornaviruses from birds and bats.

The avocet virus contained unique repetitive nucleotide motifs in its 3’UTR region.

Abstract

In this study, two novel picornaviruses (eagle/WE6/HUN/2014, PV454551-PV454552 and avocet/PA12/HUN/2018, PV454553) were detected in white-tailed eagle (Haliaeetus albicilla) and pied avocet (Recurvirostra avosetta) in Hungary, and characterized by next generation sequencing, RT-PCR and Sanger sequencing methods. The complete polyprotein coding genomes were 6,573 and 6,567 nt long and had the genome organization 5′UTRIRES-III-[VP4-VP2-VP3-VP1-2A-2B-2Chel-3A-3BVPg-3Cpro-3Dpol]-3′UTR-poly(A)n. The P1 and the 3Cpro proteins of the eagle/WE6/HUN/2014 showed 47.9% and 62.4% aa sequence identities to the corresponding proteins of the picornavirus (MT138036) from a little egret metagenome, respectively. The 2Chel/3Dpol had 44.1%/41% aa identity to the corresponding proteins of bat-origin picornaviruses (OR867633 and KX420952). The P1 protein of the avocet/PA12/HUN/2018 had 53% aa sequence identity to the P1 protein of crane70contig328 (OQ423840) from red-crowned crane metagenome; the 2Chel, 3Cpro proteins had 52.6%, 52.3% aa sequence identity to the corresponding proteins of picornavirus (MT138035) from bird metagenome and 3Dpol had 43.2% aa identity to the 3Dpol of the picornavirus (MT138036) from a little egret metagenome, respectively. The 3’UTR of avocet/PA12/HUN/2018 contained two repetitive nt sequence motifs (the 17-nt-long Motif-1 at five times forming a secondary RNA structure and the 9-nt-long Motif-2 at two times). The eagle/WE6/HUN/2014 and avocet/PA12/HUN/2019 represent the founding members of two potential novel bird-origin picornavirus species and even genera in the subfamily Heptrevirinae (family Picornaviridae).

The online version contains supplementary material available at 10.1038/s41598-026-39780-1.

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