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Original Paper	Pdf file on Synergy OPEN omments
Acta Biochim Biophys Sin 2008, 40: 693-703
doi:10.1111/j.1745-7270.2008.00449.x

The complete mitochondrial genome of the Chinese oak silkmoth, Antheraea pernyi (Lepidoptera: Saturniidae)

Yanqun Liu^1,2, Yuping Li², Minhui Pan¹, Fangyin Dai¹, Xuwei Zhu³, Cheng Lu¹*, and Zhonghuai Xiang¹

1 The Key Sericultural Laboratory of Agricultural Ministry, Southwest University, Chongqing 400716, China

2 Department of Sericulture, College of Bioscience and Biotechnology, Shenyang Agricultural University, Shenyang 110161, China

3 Sericultural Experiment Station of Henan Province, Nanyang 474676, China

Received: March 27, 2008�������

Accepted: May 26, 2008

This work was supported by grants from the National Basic Research Program of China (No. 2005cb121000), the National Natural Science Foundation of China (No. 30771630), and the Young Scholar Foundation of Shenyang Agricultural University (No. 20070112)

*Correspondence author: Tel, 86-23-68250659; Fax, 86-23-68251128; E-mail, [email protected]

We determined the complete nucleotide sequence of the mitogenome from Chinese oak silkmoth, Antheraea pernyi (Lepidoptera: Saturniidae). The 15,566 bp circular genome contains a typical gene organization and order for lepidopteran mitogenomes. The mitogenome contains the lowest A+T content (80.16%) among the known lepidopteran mitogenome sequences. An unusual feature is the occurrence of more Ts than As, with a slightly negative AT skewness (-0.021), in the composition of the major genome strand. All protein-coding genes are initiated by ATN codons, except for cytochrome oxidase subunit I, which is proposed by the TTAG sequence as observed in other lepidopterans. All transfer RNAs (tRNAs) have a typical clover-leaf structure of mitochondrial tRNA, except for tRNASer(AGN), the DHU arm of which could not form a stable stem-loop structure. Two aligned sequence blocks with a length of more than 50 bp and 90% of the sequence identity were identified in the A+T-rich region of the Saturniidae and Bombycoidae species.

Keywords� ��Chinese oak silkworm; Antheraea pernyi; mitochondrial genome; Lepidoptera: Saturniidae

Animal mitochondrial DNA (mtDNA) is generally a 14-20 kb circular DNA molecule and has a conserved set of 37 genes, including 13 protein-coding genes (PCGs), 22 transfer RNA (tRNA) genes, and two ribosomal RNA (rRNA) genes [1,2]. It additionally contains a control region of variable length known as the A+T-rich region in insects [3]. The mitochondrial genes and genomes have been widely used as an informative molecular marker for diverse evolutionary studies of animals, including phylo�genetics and population genetics [2,4-6].

As of March 2008, the complete or nearly complete mitogenomes from about 60 species of insects have been sequenced. However, only 10 complete or nearly complete mitogenomes are currently available in the GenBank for lepidopterans: Bombyx mori (accession No. AB070264) [7], Japanese B. mandarina (accession No. NC_003395) [7], Chinese B. mandarina (accession No. AY301620), Ostrinia nubilalis (accession No. NC_003367) [8], O. furnicalis (accession No. NC_003368) [8], Adoxophyes honmai (accession No. DQ073916) [9], Coreana raphaelis (accession No. DQ102703) [10], Manduca sexta (accession No. EU286785) [11], Caligula boisduvalii (accession No. EF622227) [12], and Antheraea pernyi (accession No. AY242996; submitted by this study). Newly added insect mitogenomes can provide further insight into our understanding of insect mitogenomes diversity and evolution.

Economically important silk-producing insects of order Lepidoptera belong mainly to two families, Bombycidae and Saturniidae. The mulberry silkworm B. mori, a member of the family Bombycidae, is a well-studied lepidopteran model system. The Antheraea is the largest genus among the wild silkmoths of the family Saturniidae used for silk production and contains more than 35 described species widely distributed throughout Asia. Until now, A. pernyi, A. roylei, A. proylei, A. mylitta, A. assama and A. yamamai have been commercially used for silk production. Of these, Chinese oak silkmoth A. pernyi is the best-known species. This species is commercially cultivated mainly in China, India, and Japan, and is used as a food source and for cosmetics. It is believed that A. pernyi originated in China�s Shandong Province and began being used commercially during the Han dynasty (40 BC) [13,14]. Currently, there are more than 100 varieties in China.

The mitochondrial large and small ribosomal RNA (lrRNA and srRNA) of A. pernyi have been used for phylogenetic studies [15], but the genetic information on the complete mtDNA of the species remains largely unknown. In this paper, we describe the complete mitogenome nucleotide sequence of Chinese oak silkmoth A. pernyi, the first mitogenome of an Antheraea insect used for non-mulberry silk production, and compare its sequence with other available lepidopteran mitogenomes. The mitogenome presented here can provide sequence information in primer selection and design at specific mitogenome regions for population genetics and evolutionary studies.

Materials and Methods

Mitochondrial DNA extraction from insect pupa

The fresh pupae of A. pernyi Yuzao No. 1 (univoltine) was obtained from the Yunyang Sericultural Experiment Station (Henan, China). A single pupa kept in the laboratory at -80 �C was homogenized in five volumes of a chilled sucrose-Tris-EDTA buffer (0.03 M Tris-HCl, 0.25 M sucrose, 0.01 M EDTA, pH 8.0) for cell disruption. The homogenate was centrifuged at 600 g for 10 min at 0 �C to remove any nuclear and cellular debris. The mitochondria were recovered by centrifugation at 12,000 g for 20 min at 0 �C. The pellets were used to extract the mtDNA by the alkaline lysis procedure employed by Koichiro and Tadashi [16].

PCR amplification and sequencing

The full mitogenome of A. pernyi was amplified in eight overlapping fragments by PCR amplification using insect universal primers and specific primers designed for this study (Table 1) [17]. All PCR were performed in 50 ml of total reaction volume with 1 U Ex Taq (TaKaRa, Dalian, China), 1 ml (about 20 ng) DNA, 5 ml 10�Ex Taq buffer (Mg2+ plus), 200 mM dNTPs, and 10 pmol each primer. Initially, four fragments (F1, F3, F5 and F7) of A. pernyi mitogenome were amplified using insect universal primers (Fig. 1). The PCR amplification was performed using the following procedure: 2 min at 94 �C, followed by 35 cycles of 1 min at 94 �C, 30 s at 45 �C, and 3 min at 72 �C, with a subsequent 10 min final extension at 72 �C. After purification with Gel DNA purification kit (Promega, Madison, USA), the PCR fragments were directly sequenced with the PCR primers and internal primers to complete sequences by primer walking. DNA sequencing was performed using the ABI 310 genetic analyzer (PE Applied Biosystems, Foster City, USA) and the ABI PRISM BigDye terminator sequencing kit v3.0 (PE Applied Biosystems) following the manufacturer�s protocol.

In the second step, seven newly designed PCR primers, based on information from the determined fragments, and one universal primer were used to amplify the remaining four fragments, F2, F4, F6 and F8 (Table 1) (Fig. 1). These fragments were amplified with denaturation at 94 �C for 2 min, followed by 35 cycles of 1 min at 94 �C, 30 s at 55 �C, and 3-6 min at 72 �C, with a subsequent 10 min final extension at 72 �C. Sequencing of these secondary PCR products was performed as it was in the first step.

Sequence analysis

The sequence alignment was carried out using Clustal X [18]. The PCG and rRNA genes were determined by BLAST in NCBI Entrez Database (http://blast.ncbi.nlm.nih.gov/Blast.cgi) and by comparing them with homologous regions in other insect mitogenome sequences. The PCG nucleotide sequences were translated on the basis of the invertebrate mitochondrial genetic code. The tRNA genes and its secondary structure were predicted using the tRNAscan-SE Search (http://lowelab.ucsc.edu/tRNAscan-SE/)[19]. The tRNASer(AGN) secondary structure was developed as proposed by Steinberg and Cedergren [20]. Composition skewness was calculated according to the formulas (AT skew=[A-T]/[A+T]; GC skew=[G-C]/[G+C]) [21]. Codon usage was calculated using the Countcodon program version 4 (http://www.kazusa.or.jp/codon/countcodon.html). The entire A+T-rich region was searched for tandem repeats using the Tandem Repeats Finder program (http://tandem.bu.edu/trf/trf.html) [22]. The sequence data have been deposited in GenBank under accession No. AY242996.

Results

Genome organization

The complete mitogenome of A. pernyi was 15,566 bp, similar to other sequenced lepidopteran mitogenomes, and presented the typical gene content observed in metazoan mitogenomes (Table 2) (Fig. 1): 13 PCGs, 22 tRNA genes, two rRNA subunits, and a major non-coding region known as the A+T-rich region in insects. The gene order and orientation of the A. pernyi mitogenome are identical to the completely sequenced lepidopteran mitogenomes, with the exception of C. raphaelis which has an extra tRNASer(AGN) [10]. By the translocation of tRNAMet to a position 5� upstream of tRNAIle, the lepidopteran arrangement differs from that of Drosophila yakuba, the hypothesized ancestral gene order of insects [23].�

Genome composition and skewness

The genome composition of the major strand of the A. pernyi mitogenome was heavily biased toward As and Ts, which accounted for 39.22% and 40.94%, respectively, for a total of 80.16%; Gs accounted for 7.77% and Cs 12.07% (Table 3). It is noteworthy that this bias value was the lowest among the sequenced lepidopteran mitogenomes, such as C. boisduvalii (80.62%) and C. raphaelis (82.66%). The A+T content in the sequence of the A+T-rich region was 90.40%, which was also the lowest among the available lepidopteran mitogenomes.

The base composition of nucleotide sequences can be described by skewness [21], which measures the relative number of As to Ts (AT skew=[A-T]/[A+T]) and Gs to Cs (GC skew=[G-C]/[G+C]). As shown in Table 3, the AT skewness for the major strand of the A. pernyi mitogenome was slightly negative (-0.021), indicating the occurrence of more Ts than As. Similar results were found in C. boisduvalii (-0.024), C. raphaelis (-0.047), M. sexta (-0.005) and A. honmai (-0.001). In contrast, the AT skewness was slightly positive in the other lepidopteran mitogenomes. When considering the A+T-rich region, the bias toward the use of Ts over As was more obvious in the A. pernyi mitogenome, in which the AT skewness was -0.090. For the whole set of tRNA, the AT skewness in A. pernyi had a value of zero, indicating that tRNA had an equivalent amount of Ts and As.

In all sequenced lepidopteran mitogenomes, the GC skewness values were negative (-0.158 to -0.216), meaning that there were more Cs than Gs, similar to the skewness values for dipteran mitogenomes [24]. In A. pernyi rRNA, there was a strong bias toward Cs and against Gs, and the GC skewness was -0.390. This bias was stronger than in the other genes, indicating that there was a heavy bias toward Cs and against Gs in the rRNA.

Protein-coding genes

All of the protein-coding sequences in the A. pernyi mitogenome were initiated by typical ATN codons (six with ATG, four with ATT, and two with ATA), except for cytochrome oxidase subunit I (COI) (Table 2). Sequence alignment revealed that the open reading frame of the A. pernyi COI gene also starts at a CGA codon for arginine, as found in other lepidopteran insects (Fig. 2). Because there is no regular start codon after the last stop codon upstream from the COI open reading frame, the COI gene must use an atypical start site. The initiation codon of COI translation was ambiguous, but may have occurred by the 4 bp putative initiation codon, TTAG, as previously reported in Bombyx species and C. raphaelis [7,10].

The usual TAA termination codon was found for the eight PCG in A. pernyi. Five of thirteen genes had incomplete T termination codons for COI, COII, NADH dehydrogenase subunit 3 (ND3) and ND5, while TA was incomplete for ATPase subunit 6 (ATP6) (Table 2). The COI, COII, ND3 and ND5 terminate with T exactly adjacent to tRNA, and ATP6 terminates with TA immediately followed by the ATG translation initiation codon of COIII. These incomplete stop codons are commonly found in metazoan mitochondrial genes [25]. The common interpretation of this phenomenon is that TAA termini are created via post-transcriptional polyadenylation [26].

Analysis of the base composition at each codon position of PCG in A. pernyi showed that the third codon position (92.40%) was considerably higher in A+T content than the first and second codon positions (72.00% and 70.20%, respectively). A possible explanation for this difference is that the constraints on A+T content in this first and second codon positions are less relaxed than those in the third codon position due to degenerated genetic code [27].

rRNA genes and tRNA genes

As with all other insect mitogenome sequences, two rRNA genes were present in A. pernyi. They were located between tRNALeu(CUN) and tRNAVal, and between tRNAVal and the A+T-rich region. The lengths of the A. pernyi lrRNA and srRNA were determined to be 1369 bp and 775 bp, respectively, well within the size of the known lepidopteran insects.

The tRNAscan-SE Search identified 21 tRNA genes [19], which varied from 61 bp (tRNACys) to 73 bp (tRNAAsp) in size. All 21 tRNA genes showed the typical clover-leaf secondary structures previously found in mitochondrial tRNA genes (data not shown) [10]. The A. pernyi tRNASer(AGN) gene not identified by tRNAscan-SE Search was found to be 66 bp in size. Its size was determined by comparing the conserved relative genome position and sequence similarity with other lepidopteran mitogenome sequences. The gene presented an unusual secondary structure lacking a stable stem-loop structure in the DHU arm (Fig. 3), which has been observed in several other metazoan species, including insects [1,28].

A total of 24 unmatched base pairs occurred in the A. pernyi tRNA genes. Eleven of 22 tRNA genes were found to have 20 G-U mismatches in their secondary structures. The tRNAAla gene was found to encode a U-U mismatch in the acceptor stem, and the tRNASer(UCN) encoded two U-U mismatches in the anticodon stem. The tRNAAsp gene was proposed to contain an A-A mismatch in the TyC stem. The number of mismatches in the A. pernyi tRNA is higher than in other available insect mtDNA sequences [28]. No mechanism, however, has been deduced for such high numbers of mismatches in insect mitochondrial tRNA.

Codon usage

The codons CTG and CCG were not represented in the A. pernyi mitogenome coding sequences. It was reported that the codon AGG in the B. mori and B. mandarina mitogenome would be translated as a lysine instead of a serine [29]. However, the assignment of the codon AGG in A. pernyi was unreliable and remains ambiguous [29]. The only AGG found in the A. pernyi mitogenome was therefore proposed to translate as a serine according to the invertebrate mitochondrial genetic code, as reported in A. honmai [9], which also belongs to Lepidoptera.

The use of synonymous codons in the A. pernyi mitogenome was heavily distorted, as it was in other insect mitogenomes (Table 4). The codon usage in the A. pernyi mitogenome also appears to be typical of other insect mitogenomes, where the codons have a base compositional bias for AT and a prevalence of A or T in the third position [30].

Leucine (15.02%), isoleucine (11.90%), phenylalanine (10.69%), and serine (8.75%) were the most frequent amino acids in A. pernyi mitochondrial proteins (46.36%). These amino acids are also the most frequently present in other insects, averaging 45.08% [31]. The six A+T-rich codons encoding the amino acids Asn (N), Ile (I), Lys (K), Met (M), Phe (F) and Tyr (Y) appeared 1630 times (43.8%), while the four C+G rich codons encoding the amino acids Ala (A), Arg (R), Gly (G), and Pro (P) occurred 510 times (13.7%). The overall ratio of C+G rich codons to A+T-rich codons was 0.31 in the A. pernyi mitogenome, similar to that found in other lepidopterans, including B. mori (0.28), O. nubilalis (0.29), O. furnicalis (0.30), and A. honmai (0.31). These results demonstrated that the AT mutational bias in A. pernyi affects amino acid composition to a similar degree as in other lepidopterans.

Non-coding and overlapping regions

In addition to the control region, 18 non-coding regions ranging from 1 to 56 bp (S=202 bp) were identified in the A. pernyi mitogenome (Table 2). The largest non-coding region in the A. pernyi mitogenome was 56 bp long, between tRNAGln and ND2 gene, with an A+T content of 92.9%. Seventeen other non-coding regions were scattered in short runs (1-25 bp) between neighboring genes. Nineteen base pairs were also identified as overlapping sequences varying from 1 to 8 bp in four regions (Table 2). Only one overlap with the reading frame, involving the ATP8/ATP6 genes, was found in the 13 PCGs.

A+T-rich region

The A+T-rich region is well known for the initiation of replication in both vertebrates and invertebrates [2]. The A. pernyi A+T-rich region located between the srRNA gene and tRNAMet was 552 bp in length and was within the range, from 324 bp for M. sexta to 747 bp for Japanese B. mandarina [7,11], of other lepidopteran regions. The largest open reading frame within the A+T-rich region was found to be located at position 15417-15301 bp (complementary) and encoded only 38 amino acids in length, which seems to have no functional significance.

Sequence analysis of the A. pernyi A+T-rich region revealed that it can be divided into three parts: (1) a 53 bp region bordered by the srRNA gene and a repeat region with 90.57% A+T content; (2) a repeat region composed of six 38 bp tandem repeat units with 89.59% A+T content; and (3) the 278 bp remainder of the A+T-rich region close to tRNAMet with 91.01% A+T content. The first part was found to contain a 19 bp poly-adenine stretch (position: 15040-15058, complementary), which was highly conserved among the sequenced lepidopteran mitogenomes (13-22 bp) (data not shown).

In the second part, the repeat unit contained an approximately 20 bp core motif flanked by 9 bp perfect inverted repeats [6], and it is unique only to Antheraea genus (A. pernyi, A roylei, and A. proylei). In Bombycidae species, including B. mori and B. mandarina, which are the distant relatives of A. pernyi, a repeat region corresponding to this position was also identified [7], but the nucleotide sequences between them were variable. The complete mitogenome from another Saturniidae species, C. boisduvalii, was recently determined, but no conspicuous repeats were found in the 330 bp A+T region [12].

The third part contains the highly conserved poly-thymidine stretch (close to the tRNAMet), which may be involved in controlling transcription and/or replication initiation or may have some other unknown functional role [4,32]. The alignments of this region in A. pernyi, A. proylei, A. roylei, C. boisduvalii, B. mori and B. mandarina, all members of the superfamily Bombycoidea, provided two aligned sequence blocks, each of which was more than 50 bp in length and had more than 90% sequence identity (Fig. 4).

Discussion

We have determined the first complete mitogenome sequence from an Antheraea insect, the Chinese oak silkworm A. pernyi. The A+T content of this mitogenome was the lowest among observed lepidopteran insects. The location and sequence of the non-coding regions were not conserved in other insect sequences, which would imply that these regions had no functional significance. The mitogenome of A. pernyi had gene content and organization similar to other lepidopteran mitogenomes. The gene order, however, differed from that observed in Drosophila yakuba, which is currently hypothesized to be the genetic ancestor of arthropods [23]. This suggests that the mitochondrial gene arrangement in lepidopteran insects evolved independently after splitting from its stem lineage [10].

The translational start codon for the COI gene has been extensively discussed in insects [12,33], as no typical ATN in-frame codon has been found in the proximity of the presumed start site of the gene in many insects. A tetranucleotide, ATAA, was proposed as an initiator of COI for Diptera insects, including mosquitoes and Drosophila, and two mechanisms that would permit translation to start at this sequence were suggested [34,35]. Following this reasoning, similar tetranucleotides (TTAA, GTAA and ATTA) and a hexanucleotide (ATTTAA) were proposed for COI [27,33,36,37]. Recent analysis of the transcript information from the mtDNA-encoded protein gene�s cDNA sequence revealed that the translation initiation codon for the COI gene is TCG (serine), rather than the atypical and longer codons in Diptera [33]. The initiation region for the COI gene and the precedent tRNATyr of A. pernyi and other lepidopteran insects are shown in Fig. 2. The typical ATN initiator for mitochondrial PCG is also not found at the start site for A. pernyi COI or near the tRNATyr. The plausible translation initiator for A. pernyi COI is ATT, located at the beginning of the tRNATyr gene, overlapping 3 bp with the tRNATyr; however, a codon after this triplet has a TAG-stop codon before the CGA codon, the common start of the COI open reading frame in lepidopteran insects. Thus, this ATT sequence is unlikely to be the start site for A. pernyi COI, and there are no other probable start codons for A. pernyi COI. Since no mRNA expression data for A. pernyi have been available until now, we tentatively designated the tetranucleotide TTAG sequence positioned directly upstream as an initiator for COI. In other lepidopteran insects, including B. mori, Chinese B. mandarina, Japanese B. mandarina, and C. raphaelis, the TTAG has been designated as an initiator for COI [7,10], but in the Ostrina species ATTTAG was designated [8]; in A. honmai and M. sexta CGA was designated [9,11]; and in C. boisduvalii, TTG was designated [12]. Therefore, more studies for mRNA transcripts are necessary to clarify the position of COI initiation in lepidopteran insects.

Besides the COI gene, the ND4 gene should also be considered because its putative protein sequences in some completely sequenced lepidopteran mitogenomes have shown an inconceivable sequence variation in the C-termini compared with that in the other lepidopterans (Fig. 5). Among the completely sequenced lepidopteran mitogenomes, the extreme case for the size variation is the A. honmai ND4 gene, which encodes 20 additional amino acids in the C-termini of the putative product [9], compared with the A. pernyi ND4 product. Multiple sequence alignments of the ND4 products revealed that the inconceivable sequence variation starts at amino acids 417 in B. mori NC_002355 and AY048187 and at 419 in O. furnacalis and O. nubilalis [38]. Comparing the nucleotide sequence in ND4 genes indicated that the insertion of A in B. mori NC_002355 and AY048187 (positions 3107 bp and 8431 bp, respectively), O. furnacalis (position 8211 bp) and O. nubilalis (position 8206 bp) resulted in transcript frameshifts. Once the inserted A was deleted from the four ND4 coding sequences, the putative ND4 products became well conserved (Fig. 5). The mitogenome sequence B. mori NC_002355 is the first lepidopteran mitogenome published in the GenBank database, but the Expressed Sequence Tag database (http://morus.ab.a.u-tokyo.ac.jp/cgi-bin/index.cgi) for the B. mori genome project does not match the mtDNA sequence in NC_002355 nor AY048187. These observations suggest that the insertion of A in B. mori NC_002355 (position 3107 bp) was a sequencing error, which appeared to be propagated in B. mori AY048187 [38], O. furnacalis and O. nubilalis [8].

Much research has focused on the structure and evolution of the A+T-rich region, the only major non-coding region in the mitogenome of insects [4,6,32,39,40]. The presence of varying copy numbers of tandemly repeated elements was reported to be one of the characteristics of the insect A+T-rich region [32]. Until now, the A+T-rich region for seven silkmoths belonging to the superfamily Bombycoidea, including A. pernyi, A. proylei, A. roylii, C. boisduvalii, B. mori, and B. mandarina, had been characterized. All these silkmoths, except for C. boisduvalii, harbor the repeat region in the A+T-rich region [6,7,12]. In the case of A. pernyi, the A+T-rich region harbors a repeat element of 38 bp tandemly repeated six times [6]. The A. roylei A+T-rich region has five repeat elements, rather than six repeat elements as previously reported [6]. The A. proylei, a synthetic hybrid derived from a backcross of an F1 hybrid (A. proylei�A. pernyi) female�A. pernyi male [6], shows a 99% sequence identity to A. pernyi for the complete A+T-rich region. In Japanese B. mandarina, the A+T-rich region harbors a tandem triplication of a 126 bp repeat unit, whereas in B. mori and Chinese B. mandarina, the A+T-rich region has only one repeat element [7]. Although the sequence of the repeat unit between Antheraea and Bombyx species is variable, the A+T-rich region, excluding the repeat region between Bombycoidea species, shows higher sequence identity, varying from 67% between A. pernyi and Chinese B. mandarina to 97% between A. pernyi and C. boisduvalii, suggesting that they are closely related. The presence of the conserved poly-thymidine stretch close to the tRNAMet, the conserved poly-adenine stretch close to the srRNA and two aligned sequence blocks identified in this study also supports this conclusion. Taken together, these observations allow us to conclude that the different repeat region in the A+T-rich region in Saturniidae and Bombycidae may have independent origins after these families diverged.

The gene content and order for the available lepidopteran mitogenomes are highly conserved. This fact allows us to conclude that the mitogenomes from other Antheraea species have an identical gene content and order, as observed in A. pernyi. The mitogenome has been widely used as an informative marker for insect phylogeny studies [5,9-12]. Thus, more complete mitogenome sequences from Antheraea species must be determined in order to reconstruct their phylogenetic relationships. The idea that phylogenetic relationships of Antheraea species depend mainly on phenotypic attributes is misleading [41], and the genetic information on these species remains largely unknown [42]. The repeat region in the A+T-rich region presented in Antheraea species could potentially be useful in analyzing the genetic diversity of populations, as well as phylogenetic and phylogeographic studies of the Chinese oak silkworm and other members of genus Antheraea [6]. The complete mitogenome of A. pernyi can be used as a resource on the evolutionary history and population genetics of wild silkmoths to help generate and support additional mitogenome research in the Antheraea species.

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