Characterization of the Complete Mitochondrion Genome of Diurnal Moth Amata emma (Butler) (Lepidoptera: Erebidae) and Its Phylogenetic Implications

Abstract

Mitogenomes can provide information for phylogenetic analyses and evolutionary biology. The complete mitochondrial genome of Amata emma (Lepidoptera: Erebidae) was sequenced and analyzed in the study. The circular genome is 15,463 bp in size, with the gene content, orientation and order identical to other ditrysian insects. The genome composition of the major strand shows highly A+T biased and exhibits negative AT-skew and GC-skew. The initial codons are the canonical putative start codons ATN with the exception of cox1 gene which uses CGA instead. Ten genes share complete termination codons TAA, and three genes use incomplete stop codons TA or T. Additionally, the codon distribution and Relative Synonymous Codon Usage of the 13 PCGs in the A. emma mitogenome are consistent with those in other Noctuid mitogenomes. All tRNA genes have typical cloverleaf secondary structures, except for the trnS1 (AGN) gene, in which the dihydrouridine (DHU) arm is simplified down to a loop. The secondary structures of two rRNA genes broadly conform with the models proposed for these genes of other Lepidopteran insects. Except for the A+T-rich region, there are three major intergenic spacers, spanning at least 10 bp and five overlapping regions. There are obvious differences in the A+T-rich region between A. emma and other Lepidopteran insects reported previously except that the A+T-rich region contains an ‘ATAGA’ -like motif followed by a 19 bp poly-T stretch and a (AT)9 element preceded by the ‘ATTTA’ motif. It neither has a poly-A (in the α strand) upstream trnM nor potential stem-loop structures and just has some simple structures like (AT)nGTAT. The phylogenetic relationships based on nucleotide sequences of 13 PCGs using Bayesian inference and maximum likelihood methods provided a well-supported a broader outline of Lepidoptera and which agree with the traditional morphological classification and recently working, but with a much higher support.

Mitogenomic sequences effectively recover relationships within brush-footed butterflies (Lepidoptera: Nymphalidae)

“…Based on this genetic variation, our BI and ML analyses all show strong support for relationships at different hierarchical levels (Figure 4, and Additional files 6, 7 and 8). This strong congruence is not only supported with the most recent phylogenetic studies of butterflies at family and subfamily-level [32], but is also concordant with other mitogenomic phylogenies [23, 24]. Though taxon sampling is limited across butterfly families in our mitogenomic analyses, this study demonstrates that the entire mitogenome constitutes a particularly efficient marker for studying the phylogeny of butterflies as well as other groups of insects [11, 16–18, 58].…”

Mitochondrial Genomes of Lepidopteran Insects Considered Crop Pests

“…When we compared with other reported Lepidoptera family mitogenomes, it found an identical gene order and orientation of the mitochondrial genes of this species to other lepidopteran moths, including Tryporyza incertulas [19], Corcyra cephalonica [20], Adoxophyes honmai [21], Apocheima cinerarius [22], Amata emma [23], Attacus atlas [24], Bombyx mori [25], Caligula boisduvalii [26], Chilo auricilius [19], Diaphania pyloalis [27], Manduca sexta [9], Ostrinia nubilalis, Ostrinia furnacalis [28], Samia Cynthia ricini [29], and Sasakia funebris [30], among others. The typical lepidopteran arrangement of the tRNAs (tRNA-Met, tRNA-Ile, tRNA-Gln) was observed in the T. solanivora mitogenome but differs from the order found in ancient insects (Figure 3).…”

“…Intergenic sequences S3 and S4 (17 bp) separate genes NAD6 and Cytb, and the tRNA-Ser2 and NAD1 genes, respectively. The latter sequence contains the "ATACTAA" motif, typically found in other lepidopterans [9,23,51]. This motif plays an apparent role as a recognition site for the protein implicated in mitochondrial transcription termination (mtTERM) [52].…”

“…This motif plays an apparent role as a recognition site for the protein implicated in mitochondrial transcription termination (mtTERM) [52]. Furthermore, this sequence has been recognized for being highly conserved, with a length ranging between 17 and 20 bp [23].…”

“…In S. funebris, the same (AT) 8 microsatellite was identified as that found in T. solanivora. Nevertheless, most lepidopteran mitogenomes report (AT) n , where n ranges from 7 to 12 [19,23].…”