• Journal of Sericultural and Entomological Science
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• v.45 no.1
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• pp.18-24
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• 2003

B. mandarina of Korean population apparently differs B. mori in isozyme analysis. Fourteen polymorphism occurred B. mandarina not in B. mori at 6 isozymes, Bph, Bes, Amy-hc, Ies, Ict-D, Ict-E. Korean population has shared with the Korean native strain of B. mori in B genotype of Bes, F of Amy-hc, n of Ict-E, M and S of Ict-H. These 5 genotype were known that detection only Korean native strains of B. mori. Nei's genetic distance based on the genotype of isozyme and hemolymph protein using 4 populations of B. mandarina varied from 0.0350 to 0.0624. The distances of 0.0350 is between Jinju and Chilgok population and between Jinju and Kosung population has the largest distances, 0.0624. In genus of Bombyx, B. mandarina and B. mori, genetic distance varied from 0.3822 to 0.5074. Phylogenetic tree obtained using the subprogram UPGMA of NTSYS represented that Bombyx devided two group, B. mandarina and B. mori. B. mandarina has genetic differences according to the population within the Korean peninsula, but that was not recognized genetic variation or divergence considering low values of genetic distance.

• Proceedings of the Korean Society of Sericultural Science Conference
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• 2003.04a
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• pp.42-42
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• 2003

The wild silkworm, Bombyx mandarina, was believed the only ancestor of B. mori, inhabits the limited area of Eastern Asia including China, Korea and Japan. However, the geographic dimorphism of B. mandarina was reported with chromosome number and arylphorin gene. In connection with those dimorphism, we studied the genetic differences of ITS-2 region in rDNA purposing the differentiation and geographic variation within the species of B. mandarina. (omitted)

• Journal of Sericultural and Entomological Science
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• v.27 no.1
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• pp.37-41
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• 1985

The haemolymph protein, digestive fluid proteins and digestive fluid amylase activity of wild silkworm, Theophila mandarina those of the were studied by polyacrylamide gel electrophoresis. In addition, they was also compared with silkworm. 1. 6 main protein bands in female and 7 main protein bands in male were detected in the larval haemolymph of T. mandarina where as 8 and 7 main protein bands in female and male of B. mori were observed. Some differences in the haemolymph protein ands of T. mandarina and B. mori were observed. 2. 15 protein bands and 12 protein bands were found in the larval digestive fluid of T. mandarina and B. mori respectively. Some differences in the mobility of digestive fluid proteins of T. mandarina and B. mori were noticed. 3. Larval digestive fluid amylases were anionic and moved near the tracking dye in both T. mandarina and B. mori. Mobility of the digestive fluid amylases relative to bromophenol blue were 0.019 and 0.020 in T. mandarina and B. mori respectively.

• International Journal of Industrial Entomology and Biomaterials
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• v.33 no.2
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• pp.113-120
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• 2016

Bombyx mandarina is widely accepted as ancestor of B. mori. Silkworms are served as well-characterized models for understanding the mechanism for the genetic regulation of development. In this study, we performed RNA-Seq analysis to examine tissue-expression of gloverin isoforms of the silk-gland, mid-gut, and fat body in B. mandarina. BLAST analysis revealed that four gloverin isoform gene sequences of B. mandarina were highly similar to B. mori. To identify the difference between two species, the expression profile of gloverin was measured by semi- RT-PCR analysis. The specific expression of gloverin isoform genes was observed mainly in the fat body from B. mori but not B. mandarina. However, all of tissues in the wild-type silkworm could induce the upregulation of compared with the B. mori. To validate the sudden increase in gloverin gene expression in the mid-gut tissue of B. mandarina, we were using qRT-PCR. Relative mRNA expression rate of gloverin at the wild-type silkworm was much higher than domestic silkworm. Comparative genomics between domesticated and wild silkworms showed different tissue-expression levels in some of immune related genes. These results are suggesting a trend toward decreasing immunity related genes expression during domestication. Further studies are needed to elucidate the silkworm domestication and an invaluable resource for wild silkworm genomics research.

• International Journal of Industrial Entomology and Biomaterials
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• v.1 no.1
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• pp.9-17
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• 2000

Genetic variation in the domestic silkworm strains (Bombyx mori) and phylogenetic relationships between domestic silkworms and wild silkworms (B. mandarina) were investigated by using a portion of mitochondrial CGI gene sequences. Ten geographic strains of B. mori we sequenced were identical in the 410 bp-section of mitochondrial COI gene. This sequence was also identical to the homologous sequence of the four Gen-Bank-registered strains, but one strain of B. mori differed a single nucleotide (0.2%) from others. MtDNA homogeneity in the B. mori strains appears to be resulted from fixation into the mast frequent mtDNA type during the course of breeding for new strains, in which an extensive indoor rearing and removal of unwanted individuals were accompanied. In the comparisons between domestic and wild silkworms, some wild silkworms were closely related to domestic silkworms (0.2%-1.2% of divergence), but the others were not (2.7%-3.7% of sequence divergence). This result was also reflected in the phylogenetic analyses, showing two independent phylogenetic groups: one including all B. mandarina sequences and the other including both B. mandarina and B. mori sequences. Thus, domestic silkworms may have been derived from the ancestor of B. mandarina, which belongs to this group, alto-ough more extensive study will provide better understanding on this issue.

• International Journal of Industrial Entomology and Biomaterials
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• v.10 no.2
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• pp.101-106
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• 2005

In this study, we describe the Bombyx mandarina hemolin cDNA. A sequence analysis of cDNA revealed a single open reading frame (ORF) of 1233 nucleotides. The deduced 410 amino acid sequence of B. mandarina hemolin contains 4 imunoglobulin (Ig) C-2 type domains. B. mandarina hemolin cDNA showed the highest sequence homology to known those of B. mori. The developmental profile in terms of expression level of hemolin mRNA was determined in the absence of a bacterial challenge. Hemolin mRNA was detected only in mid-gut, but not in hemocytes, fat body, testis, and silkglands. Hemolin mRNA in mid-gut was not detected until the spinning stage of the last instar larva, however, lit dramatically increased at the beginning of spinning and gradually decreased until pupal stage.

• Journal of Sericultural and Entomological Science
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• v.41 no.3
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• pp.147-153
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• 1999

Chitinolytic enzymes such as ${\beta}$-N-acetylglucosaminidase are major hydrolases involved in insect molting. We have isolated, sequenced a CDNA encoding ${\beta}$-N-acetylglucosaminidase from the silkworm, Bombyx mandarina, and compared its sequence with genes encoding chitinolytic enyzmes from other sources. The insert DNA in the clone is 3,284 nucleotides long with an open reading frame of 1,788 nucleotides that encodes a protein of 596 amino acids with a molecular weight of 68.2 kDa. There is a 3’-untranslated region composed with 1.479 nucleotides and are several potential polyadenylation signals. The predicted amino acid sequence apparently contains a leader peptide of 23 amino acids. A search of the amino acids sequence databases for sequences similarities to other ${\beta}$-N-acetylglucosaminidases or ${\beta}$-N-acetylhexosaminidases. The highest similarity matched with the enzyme from B. mori, which has a sequence identity of 95%. On the other hand, the identity between the B. mandarina enzyme and those from M. sexta and human are 70% and 24%, respectively.

• Journal of Life Science
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• v.9 no.1
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• pp.84-89
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• 1999

To determine phylogenetic relatedness of four silk-producing silkmoths (B. mori, B. mandarina, A. yamamai and A. pernyi), internal coding region of arylphorin which is a storage protein in hemolymph protein of insects were amplified by polymerase chain reaction and then sequenced and compared each other. The nucleotide composition was biased toward adenine and thymine(59% A+T) and a strong bias for use of C in the third position of codons was found for Phe and Tyr. Together TTC(Phe) and TAC(Tyr) account for about 16.8% (10 for TTC and 8 for TAC) of all codon usage. The nucleotide similarity of arylphorin gene from B. mori showed 99%, 98% and 97% homology with those of B. mandarina, A. yamamai and A. pernyi, respectively. Also, the nucleotide sequence of arylphorin gene from B. mandarina showed 98% and 97% homology with those of A. yamamai and A.pernyi, respectively. Between A. yamamai and A. pernyi, the sequence homology was 97%. The deduced amino acid sequences in B. mori, B. mandarina and A. yamamai showed almost 99% homology. Although the aryphorin gene provided insufficient variability among the four insect species, A UPGMA tree is generated that supported the monophyly of silk-producing insects, with M. sexta placed basal to it. It is suggest that silk-producing insects have a close relationship and a homogeneous genetic background from comparison with those of other insects.

• Journal of Life Science
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• v.9 no.4
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• pp.341-347
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• 1999

Insects use chitinolytic enzyme to digest chitin in the exoskelton during the molting process. We have isolated and sequenced a chitinase-encoding cDNA from the silkworm, Bombyx mandarina, compared its sequenced with genes encoding chitinolytic enzymes from other sources. The insert DNA in the clone is 2,675 nucleotides long with an open reading frame of 1,695 uncletides that encodes a protein of 565 amino acids with a molecuar weight of 63.4 kDa. The 3' -untranslated region of 889 nucleotides is AT-rich and contains two putative polyadenylation signals. The N-terminal sequence of the encoded protein contains numerous hydrophobic residues characteristic of a leader peptide. The amino acid alignment revealed that the endo-$\beta$-N-acetylglucosaminidase had 83% and 97% homology with M. sexta and B. mori, respectively. The deduced amino acid had two highly conserved region at the amino acid residues 97-111 and 139-148 that were related to the existing chitinase.

• Proceedings of the Korean Society of Sericultural Science Conference
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• 2002.10a
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• pp.19-20
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• 2002

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