Characterization of mitochondrial genome of Chinese wild mulberry silkworm, Bomyx mandarina (Lepidoptera: Bombycidae)

Abstract

The complete mitochondrial genome of Chinese Bombyx mandarina (ChBm) was determined. The circular genome is 15682 bp long, and contains a typical gene complement, order, and arrangement identical to that of Bombyx mori (B. mori) and Japanese Bombyx mandarina (JaBm) except for two additional tRNA-like structures: tRNA( Ser(TGA))-like and tRN( AIle(TAT))-like. All protein-coding sequences are initiated with a typical ATN codon except for the COI gene, which has a 4-bp TTAG putative initiator codon. Eleven of 13 protein-coding genes (PCGs) have a complete termination codon (all TAA), but the remaining two genes terminate with incomplete codons. All tRNAs have the typical clover-leaf structures of mitochondrial tRNAs, with the exception of tRNA( Ser(TGA))-like, with a four stem-and-loop structure. The length of the A+T-rich region of ChBm is 484 bp, shorter than those of JaBm (747 bp) and B. mori (494-499 bp). Phylogenetic analysis among B. mori, ChBm, JaBm, and Antheraea pernyi (Anpe) showed that B. mori is more closely related to ChBm than JaBm. The earliest divergence time estimate for B. mori-ChBm and B. mori-JaBm is about 1.08+/-0.18-1.41+/-0.24 and 1.53+/-0.20-2.01+/-0.26 Mya, respectively. ChBm and JaBm diverged around 1.11+/-0.16-1.45+/-0.21 Mya.

Complete sequence of the mitochondrial genome of the Japanese buff-tip moth, Phalera flavescens (Lepidoptera: Notodontidae)

“…This region was located between the rrnS and trnM genes as we expected, with the A+T content of 93.2%, which is also well within the range of other lepidopterans from 88.0% in A. melete ) to 98.5% in Phthonandria atrilineata Twenty-six lepidopteran species in this study arranged from the shortest to the longest in the size of the non-D-loop region. The microsatellite-like (AT) 6 , ACC(AT) 6 and 16-bp poly-T elements were present in the flanking area of the P. flavescens D-loop region, and this case is similar to that found in other lepidopterans, such as ATTTA(AT) 7 , ATTTA(TA) 8 , ATTTA(AT) 9 , ATTTA(AT) 10 , ATTTA(AT) 7 (TA) 3 , and ATTTA(AT) 11 in C. raphaelis, M. sexta, B. mandarina, B. mori, O. lunifer, and A. melete, respectively (Yukuhiro et al, 2002;Kim et al, 2006;Pan et al, 2008;Cameron and Whiting, 2008;Hu et al, 2010;Liao et al, 2010). The motif poly-T stretch was located upstream of the rrnS 5'-end and preceded by the oligonucleotide ATAGA, and this structural feature is remarkably conserved in the majority of lepidopteran insects ( Figure 5).…”

Little gene flow between domestic silkmoth <i>Bombyx mori</i> and its wild relative <i>Bombyx mandarina</i> in Japan, and possible artificial selection on the <i>CAD</i> gene of <i>B. mori</i>

“…2). These results were consistent with mitochondrial DNA-based analyses (ND5: Yukuhiro et al (2002); COI: Pan et al (2008); Yukuhiro et al (2011)) despite the lower variation in CAD. As described in Yukuhiro et al (2011), the present findings suggest that little gene flow occurs between B. mori and Japanese B. mandarina, although fertile hybrids between them have been generated under artificial conditions.…”

Complete mitochondrial genome of the Five-dot Sergeant <I>Parathyma sulpitia</I> (Nymphalidae: Limenitidinae) and its phylogenetic implications

“…Additionally, a motif ATAGA followed by 19 bp poly-T, which has been suggested as the structural signal for the recognition of proteins in the replication initiation of minor-strand mtDNA, was detected, which is similar to that observed in other lepidopteran species such as the Bombyx mori (Yukuhiro et al, 2002). Finally, a few of multiple short microsatellite-like repeat regions, such as the (AT) 7 located 195 bp upstream from rnnS and preceded by the ATTTA motif, were present, which was as expected as they are also detected in the majority of other sequenced lepidopterans (Hong et al, 2008;Hu et al, 2010;Kim et al, 2009;Mao et al, 2010;Pan et al, 2008;Wang et al, 2011;Xia et al, 2011). As for the tRNA-like sequences and the tandemly repeated elements often reported in other lepidopteran species (Kim et al, 2009;Pan et al, 2008), no relevant structures were detected in the P. sulpitia A+T-rich region.…”