Genome organization and molecular characterization of the threeFormica exsectaviruses—FeV1, FeV2 and FeV4

Abstract

We present the genome organization and molecular characterization of the three Formica exsecta viruses, along with ORF predictions, and functional annotation of genes. The Formica exsecta virus-4 (FeV4; GenBank ID: MF287670) is a newly discovered negative-sense single-stranded RNA virus representing the first identified member of order Mononegavirales in ants, whereas the Formica exsecta virus-1 (FeV1; GenBank ID: KF500001), and the Formica exsecta virus-2 (FeV2; GenBank ID: KF500002) are positive single-stranded RNA viruses initially identified (but not characterized) in our earlier study. The new virus FeV4 was found by re-analyzing data from a study published earlier. The Formica exsecta virus-4 genome is 9,866 bp in size, with an overall G + C content of 44.92%, and containing five predicted open reading frames (ORFs). Our bioinformatics analysis indicates that gaps are absent and the ORFs are complete, which based on our comparative genomics analysis suggests that the genomes are complete. Following the characterization, we validate virus infection for FeV1, FeV2 and FeV4 for the first time in field-collected worker ants. Some colonies were infected by multiple viruses, and the viruses were observed to infect all castes, and multiple life stages of workers and queens. Finally, highly similar viruses were expressed in adult workers and queens of six other Formica species: F. fusca, F. pressilabris, F. pratensis, F. aquilonia, F. truncorum and F. cinerea. This research indicates that viruses can be shared between ant species, but further studies on viral transmission are needed to understand viral infection pathways.

Ever-increasing viral diversity associated with the red imported fire ant Solenopsis invicta (Formicidae: Hymenoptera)

“…Using a transcriptome approach, we searched for RNA viruses in the SRA data collected from S. invicta. Curiously, while a great diversity of positive and negative sense viruses have been reported from ants [9,10] and other arthropods [2], the S. invicta virome has been composed mainly of ssRNA viruses in the order Picornavirales, with no negative sense RNA viruses previously reported. One factor that could be responsible for this bias is the selection of polyadenylated RNA for library preparation in previous studies [11,30].…”

“…Nonetheless, like insect diversity, the diversity of viruses associated with insects is far from clear [1,3]. While many studies have focused on viromes of arbovirus-transmitting insects, especially those involved in transmission of medically important viruses, such as mosquitoes [5][6][7][8], other groups that are important pests either impacting agricultural or natural ecosystems, such as invasive ants, have been less studied [9][10][11]. In addition to contributing to better understanding of basic aspects of virus ecology and evolution, these studies may contribute to new opportunities to use viruses as tools to develop more sustainable insect control methods [12][13][14].…”

ICTV Virus Taxonomy Profile: Nyamiviridae 2021

“…Orinoco virus (genus Orinovirus) was found in moths, and a nyamivirus associated with tapeworms is classified in the genus Tapwovirus. Members of the genus Formivirus are associated with ants and wasps [5,6]. Viruses assigned to each genus form weak monophyletic clades on phylogenetic analysis of L protein sequences.…”

Ever-increasing viral diversity associated with the red imported fire ant Solenopsis invicta (Formicidae: Hymenoptera)

“…Nonetheless, like insect diversity, the diversity of viruses associated with insects is far from clear (1,3). While many studies have focused on viromes of arbovirus-transmitting insects, especially those involved in transmission of medically important viruses, such as mosquitoes (5)(6)(7)(8), other groups that are important pests either impacting agricultural or natural ecosystems, such as invasive ants, have been barely studied (9)(10)(11). In addition to contributing to better understanding of basic aspects of virus ecology and evolution, these studies may contribute to new opportunities to use viruses as tools to develop more sustainable insect control methods (12)(13)(14).…”