We report 37 mitochondrial genome (mitogenome) sequences of Bombyx mori strains (Lepidoptera: Bombycidae) and four of B. mandarina individuals, each preserved and collected, respectively, in South Korea. These mitogenome sequences combined with 45 public data showed a substantial genetic reduction in B. mori strains compared to the presumed ancestor B. mandarina, with the highest diversity detected in the Chinese origin B. mori. Chinese B. mandarina were divided into northern and southern groups, concordant to the Qinling–Huaihe line, and the northern group was placed as an immediate progenitor of monophyletic B. mori strains in phylogenetic analyses, as has previously been detected. However, one individual that was in close proximity to the south Qinling–Huaihe line was exceptional, belonging to the northern group. The enigmatic South Korean population of B. mandarina, which has often been regarded as a closer genetic group to Japan, was most similar to the northern Chinese group, evidencing substantial gene flow between the two regions. Although a substantial genetic divergence is present between B. mandarina in southern China and Japan, a highly supported sister relationship between the two regional populations may suggest the potential origin of Japanese B. mandarina from southern China instead of the Korean peninsula.
Antheraea yamamai, also known as the Japanese oak silk moth, is a wild species of silk moth. Silk produced by A. yamamai, referred to as tensan silk, shows different characteristics such as thickness, compressive elasticity, and chemical resistance compared with common silk produced from the domesticated silkworm, Bombyx mori. Its unique characteristics have led to its use in many research fields including biotechnology and medical science, and the scientific as well as economic importance of the wild silk moth continues to gradually increase. However, no genomic information for the wild silk moth, including A. yamamai, is currently available. In order to construct the A. yamamai genome, a total of 147G base pairs using Illumina and Pacbio sequencing platforms were generated, providing 210-fold coverage based on the 700-Mb estimated genome size of A. yamamai. The assembled genome of A. yamamai was 656 Mb (>2 kb) with 3675 scaffolds, and the N50 length of assembly was 739 Kb with a 34.07% GC ratio. Identified repeat elements covered 37.33% of the total genome, and the completeness of the constructed genome assembly was estimated to be 96.7% by Benchmarking Universal Single-Copy Orthologs v2 analysis. A total of 15 481 genes were identified using Evidence Modeler based on the gene prediction results obtained from 3 different methods (ab initio, RNA-seq-based, known-gene-based) and manual curation. Here we present the genome sequence of A. yamamai, the first genome sequence of the wild silk moth. These results provide valuable genomic information, which will help enrich our understanding of the molecular mechanisms relating to not only specific phenotypes such as wild silk itself but also the genomic evolution of Saturniidae.
The complete mitochondrial genomes (mitogenomes) of two DNA barcode-defined haplotypes of Metcalfa pruinosa and one of Salurnis marginella (Hemiptera: Flatidae) were sequenced and compared to those of other Fulgoroidea species. Furthermore, the mitogenome sequences were used to reconstruct phylogenetic relationships among fulgoroid families. The three mitogenomes, including that of the available species of Flatidae, commonly possessed distinctive structures in the 1702–1836 bp A+T-rich region, such as two repeat regions at each end and a large centered nonrepeat region. All members of the superfamily Fulgoroidea, including the Flatidae, consistently possessed a motiflike sequence (TAGTA) at the ND1 and trnS2 junction. The phylogenetic analyses consistently recovered the familial relationships of (((((Ricaniidae + Issidae) + Flatidae) + Fulgoridae) + Achilidae) + Derbidae) in the amino acid-based analysis, with the placement of Cixiidae and Delphacidae as the earliest-derived lineages of fulgoroid families, whereas the monophyly of Delphacidae was not congruent between tree-constructing algorithms.
Gastroesophageal reflux disease (GERD) is a globally prevalent disease and results from a reflux of gastric contents into the esophagus. Existing synthetic drug‐based treatments for GERD have various drawbacks including refractory symptoms, relapse, or resistance due to long‐term use or may result in mucosal degeneration, polyps, and osteoporosis.Semisulcospira gottschei(SE), a freshwater snail, has been generally consumed as a food source due to its excellent flavor and nutritional value in Korea and considered to have therapeutic properties for various diseases including dyspepsia, stomachache, and hepatic diseases. The present study aims to investigate whetherSemisulcospira gottscheiextract (SGE) has a protective effect on reflux esophagitis‐induced rat models. The anti‐inflammatory effects of SGE were evaluated via NO production in LPS‐induced Raw 264.7 macrophage. And the protection effects of SGE were analyzed by assessing the amelioration of mucosal damage and expression of inflammation‐associated proteins in reflux esophagitis (RE) rats. Our results indicate that SGE significantly suppressed NO production in LPS‐induced raw 264.7 cells without any cytotoxicity. We observed mucosal lesions and histological changes in the esophagus of RE control rats. However, SGE treatment markedly ameliorated mucosal lesion ratio indicated through histological changes. SGE administration suppressed the expression of proteins related to inflammation, such as p‐NF‐κB, p‐IκBα, COX‐2, and TNF‐α, in esophageal tissue. Moreover, SGE elevated the expression of claudin‐5, which is a tight junction protein, involved in barrier function of epithelium and endothelium. The results suggest that SGE is useful as a medicinal food in esophagitis and may be helpful in developing effective treatment protocols for GERD.
The flatid planthopper, Metcalfa pruinosa (Hemiptera: Flatidae), which is an invasive species, is widespread in Korea. We sequenced a fragment of the COI from 536 individuals collected mainly in Korea and the European countries and combined these sequence data with the public data, totaling 830 individuals worldwide. The identification of one shared haplotype only between Korea and the USA, the presence of this haplotype only in the North-West region of Korea, and the highest haplotype diversity in this region suggested that the North-West region is another point of entry in addition to the South-East region, which is the presumed sole point of entry to Korea. Furthermore, it suggested that North-West entry involves the M. pruinosa originating from the USA. In an effort to find further variable regions in the mitochondrial genome, one region provided substantially increased variability compared to that of the fragment of COI. FST estimation, PCoA, and BAPS analysis, using the concatenated sequences of COI and the newly detected variable region to infer the expansion pattern in Korea, indicates that the main highway, running obliquely between the North-West and South-East regions, appears to be responsible for the current population genetic structure of M. pruinosa in Korea, facilitating gene flow through this highway traffic.
Conogethes pinicolalis has long been considered as a Pinaceae-feeding type of the yellow peach moth, C. punctiferalis, in Korea. In this study, the divergence of C. pinicolalis from the fruit-feeding moth C. punctiferalis was analyzed in terms of morphology, ecology, and genetics. C. pinicolalis differs from C. punctiferalis in several morphological features. Through field observation, we confirmed that pine trees are the host plants for the first generation of C. pinicolalis larvae, in contrast to fruit-feeding C. punctiferalis larvae. We successfully reared C. pinicolalis larvae to adults by providing them pine needles as a diet. From a genetic perspective, the sequences of mitochondrial COI of these two species substantially diverged by an average of 5.46%; moreover, phylogenetic analysis clearly assigned each species to an independent clade. On the other hand, nuclear EF1α showed a lower sequence divergence (2.10%) than COI. Overall, EF1α-based phylogenetic analysis confirmed each species as an independent clade, but a few haplotypes of EF1α indicated incomplete lineage sorting between these two species. In conclusion, our results demonstrate that C. pinicolalis is an independent species according to general taxonomic criteria; however, analysis of the EF1α sequence revealed a short divergence time.