Combined Venom Gland Transcriptomic and Venom Peptidomic Analysis of the Predatory Ant Odontomachus monticola

Abstract

Ants (hymenoptera: Formicidae) have adapted to many different environments and have become some of the most prolific and successful insects. To date, 13,258 ant species have been reported. They have been classified into 333 genera and 17 subfamilies. Except for a few Formicinae, Dolichoderinae, and members of other subfamilies, most ant species have a sting with venom. The venoms are composed of formic acid, alkaloids, hydrocarbons, amines, peptides, and proteins. Unlike the venoms of other animals such as snakes and spiders, ant venoms have seldom been analyzed comprehensively, and their compositions are not yet completely known. In this study, we used both transcriptomic and peptidomic analyses to study the composition of the venom produced by the predatory ant species Odontomachus monticola. The transcriptome analysis yielded 49,639 contigs, of which 92 encoded toxin-like peptides and proteins with 18,106,338 mapped reads. We identified six pilosulin-like peptides by transcriptomic analysis in the venom gland. Further, we found intact pilosulin-like peptide 1 and truncated pilosulin-like peptides 2 and 3 by peptidomic analysis in the venom. Our findings related to ant venom peptides and proteins may lead the way towards development and application of novel pharmaceutical and biopesticidal resources.

The Peptide Venom Composition of the Fierce Stinging Ant Tetraponera aethiops (Formicidae: Pseudomyrmecinae)

“…The consensus sequence of the prepro-region of Tetraponera aethiops venom peptides shared 43%, 35%, 52%, and 48% with the consensus prepro-regions sequences obtained from previous studies on Odontomachus monticola [26], Myrmecia pilosula [27], Myrmecia gulosa [28], and Tetramorium bicarinatum (Superfamily A) [29], respectively. [26], Myrmecia gulosa [28], Myrmecia pilosula [27], and Tetramorium bicarinatum (Superfamily A) [29] venoms. Alignments were generated with the Muscle program in Seaview version 4.6.1 and edited using BOXSHADE version 3.2.…”

“…Similar residues are highlighted in blue. The consensus sequence of the prepro-region of Tetraponera aethiops venom peptides shared 43%, 35%, 52%, and 48% with the consensus prepro-regions sequences obtained from previous studies on Odontomachus monticola [26], Myrmecia pilosula [27], Myrmecia gulosa [28], and Tetramorium bicarinatum (Superfamily A) [29], respectively. peptide precursors from Tetraponera aethiops venom were submitted to GenBank (for accession numbers, see the legend to Figure 4).…”

“…Tetraponera aethiops peptide precursors seemed to be related to other venom peptide precursors reported for ants. Indeed, this consensus sequence shared 43%, 35%, 52%, and 48% sequence identity with consensus prepro-sequences obtained from studies on Odontomachus monticola [26], Myrmecia pilosula [27], Myrmecia gulosa [28], and Tetramorium bicarinatum venoms [29], respectively ( Figure 3). Unlike prepro-regions, mature regions of these precursors exhibited much more intra-and interspecific amino acid sequence variabilities ( Figure 4).…”

“…The venom peptidome of T. aethiops is also substantially less complex than the predatory ant Tetramorium bicarinatum venom peptidome, which is encoded by 37 peptide genes belonging to three superfamilies [29]. However, this peptide diversity is similar to those of other ants with a dual use of offensive/defensive venom such as Myrmecia gulosa [28] and Odontomachus monticola [26]. Different venom compositions have also been noted in the subfamily Pseudomyrmecinae according to a mass spectrometry-based investigation.…”

“…RNAseq data are available on the European Nucleotide Archive website (https://www.ebi.ac.uk/ena) under the following study accession number: PRJEB35699. [26], Myrmecia gulosa [28], Myrmecia pilosula [27], and Tetramorium bicarinatum (Superfamily A) [29] venoms. Alignments were generated with the Muscle program in Seaview version 4.6.1 and edited using BOXSHADE version 3.2.…”