• International Journal of Industrial Entomology and Biomaterials
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• v.5 no.1
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• pp.23-32
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• 2002

The introduction of hybrid and exploitation of heterosis has played a vital role in Indian sericulture industry, which clearly depicts a quantum jump in silk production during the last four decades. Since, the introduction of heterosis, progress in silkworm breeding has depended on success or failure in identifying better combiners. Systematic procedures developed have enabled the breeders to identify the best combiners by combining ability test, line ${\TIMES}$ tester analysis or $D^2$ analysis for maximum expression of heterosis. The level of heterosis expressed in the crossbreed population is determined by the interaction between genotype and prevailing environmental factors. Except some of the pre and post cocoon parameters, heterosis is invariably higher in single crosses compared to three-way and double crosses. However, during hot and humid season, when rearing of F1 bivoltine hybrid is unsuccessful at field level and indigenous races results in very low and poor quality yield, three-way and double crosses can play an important role as an intermediary technology. The objective of this article is to review briefly the concept and causes of heterosis, utilization of different forms of heterosis in silk production and its significance in silkworm, Bombyx mori breeding.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1994.04a
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• pp.243-243
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• 1994

Although active systemic anaphylaxis and passive cutaneous anaphylaxis have been empolyed to study anaphylactic hypersensitivity, it is difficult and time-consuming to induce these reactions in experimental animals. In recent, Jun et al have found a simple method to induced anaphylactic hypersensitivity such as anaphylactic shock(AS) and cutaneous reaction(CR) using compound48/80. Cortex mori (Morus alba L.), the root bark of mulberry tree has been used as an antiphlogistic, diuretic, and expectorant in herbal medicine. The purpose of this study was to determine whether the methanol extract of Cortex mori could inhibit the compound 48/80-induced AS and CR. To induce AS, various doses of compound 48/80 (5, 7.5, 10, 15$\mu\textrm{g}$/gm B.W.) were injected intraperitoneally (i.p.) into ICR mice. The animals were pretreated by three injection(i.p.) of Cortex mori before compound 48/80 administration. Peripheral blood was collected from the right ventricle to estimate the level of serum histamine at 15 minutes after the injctin(i.p.) of various concentration of compound48/80. Mortility rate, mean death time and mesenteric mast cell degranulation rate were evaluated over a 72 hour period. To estimate the effect of Cortex mori on compound 48/80-induced cutaneous reaction, various doses of compound 48/80 with or without Cortex mori were injected intradermally(i.d.) into the shaved flank of Sprague-Dawley rats, and the blue cutaneous patchs induced by Evans'blue injection at the compound 48/80 alone and Cortex mori plus compound 48/80 injection sites were observed. As a Parameter of these reactions, the levels of histamine in the supernatant, calcium uptake and intracellular CAMP of RPMC were measured. supernatant, 1)compound 48/80-induced mortility rate, mean death time, mesenteric mast cell degranulation rate, and serum histamine level in ICR mice were significantly inhibited by pretreatment of Cortex mori, 2) cutaneous reaction inducd by compound48/80 was well developed in Sprague-Dawley rat, but Cortex mori inhibited the compound 48/80-induced blue patch formation remarkably, 3) the compound 48/80-induced degranulation, histamine release and calcium uptake of RPMC pretreated with Cortex mori were significantly inhibited, compared to those of control without Cortex mori pretreatment, and 4)the level of cAMP of RPMC was reduced bythe increased concentration of compound 48/80, pretreatment of Cortex mori not only inhibited the compound 48/80-induced reduction of CAMP but also significantly increased the level of cAMP naturally, from the above results, it is suggested that Cortex mori has an some substances with an ability to inhibits the compound 48/80-induced AS,CR, and mast cell activation.

• International Journal of Industrial Entomology and Biomaterials
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• v.31 no.2
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• pp.85-89
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• 2015

This peptide has antibacterial activity against several Gram-positive and Gram-negative bacteria. Bombyx mori cecropinB1(BmCecB1) is antimicrobial peptides from Bombyx mori and belongs to cecropin family. Antimicrobial peptides are important components of the innate immune systems in all living organism. To produce the BmCecB1 antimicrobial peptide, we constructed transgenic silkworm that expressed BmCecB1 gene under the control BmA3 promoter using piggyBac vector. The use of the 3xP3-driven EGFP cDNA as a marker allowed us to rapidly distinguish transgenic silkworm. Mixtures of the donor vector and helper vector were micro-injected into 600 eggs of bivoltin silkworms, Baegokjam. In total, 49 larvae (G0) were hatched and allowed to develop into moths. The resulting G1 generation consisted of 22 broods, and we selected 2 broods containing at least 1 EGFP-positive embryo. The rate of successful transgenesis for the G1 broods was 9%. We identified 9 EGFP-positive G1 moths and these were backcrossed with wild-type moths. With the aim of identifying a BmCecB1 as antimicrobial peptide, we investigated the Radical diffusion Assay (RDA) and then demonstrated that BmCecB1 possesses high antibacterial activities against Gram-negative bacteria.

• 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.

• International Journal of Industrial Entomology and Biomaterials
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• v.4 no.1
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• pp.63-68
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• 2002

A cDNA encoding a putative member of cathepsin B of the thiol pretense superfamily was cloned from a cDNA library of the mulberry longicorn beetle, Apriona germari. Sequence analysis of the cDNA encoding the cathepsin B of A. germari (AgCatB) revealed that the 972 bp cDNA has an open reading frame of 324 amino acid residues. The deduced protein sequence of the AgCatB showed high homology with cathepsin B of the insects, Bombyx mori (47.3% amino acid identity), Helicoverpa armigera (46.6%) and Sarcophaga peregrina (45.6%), and the lowest homology with Aedes aegypti (33.2%). The AgCatB contains six disulfate bonds typical for cysteine pretenses. The three amino acid positions Cys-109, His-267, and Asn-287 which are conserved, active sites characteristic for cathepsin B, were also found. Phylogenetic analysis further confirmed that the AgCatB has a close relationship with that of B. mori, H. armigera and S. peregrina.

• Korean journal of applied entomology
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• v.45 no.3 s.144
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• pp.283-291
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• 2006

The efficiency to detect mutagenicity of the system using a specific locus mutation of Bombyx mori was examined and improved. In the system, mutagenicity could be detected by the egg colour manifested by the pe and/or re genes, which is a kind of recessive visible mutation of the insect. Among tested four mutagens, MMC had specially high sensitivity in the oocytes of silkworm and EMS had in the spermatozoa. PCB and dioxin showed a positive effect in both the oocytes and spermatozoa. In a consequence of sensitivity of mutagen by mating number of male moth of B. mori, treated mutagen, there was no difference between one mating - and three mating - male moth in sensitivity of mutagen. Sun3ho, B. mori variety, which showed high sensitivity to mutagens was improved in the major characteristics by crossing of C5 and N12.

• BMB Reports
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• v.33 no.1
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• pp.63-68
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• 2000

Most baculoviruses have an ecdysteroid UDP-glucosyltransferase (egt) gene, whose product inactivates ecdysteroid within the infected host. Bomhyx mori larvae infected with BmEGTZ, a mutant B. mori nucleopolyhedrovirus (BmNPV) in which the egt gene has been inactivated, die more rapidly compared to larvae infected with wild-type BmNPV. In this study, the profile of hemolymph proteins, and progression of virus infection in BmEGTZ- and BmNPV-infected B. mori larvae, was analyzed by SDS-PAGE and histochemically. These analyses showed that virus-encoded and virus-induced proteins were expressed quicker in BmEGTZ-infected larvae than in BmNPV-infected larvae. This suggests that the decrease in time to death, following BmEGTZ infection, results from the stimulation of virus-specific protein expression. In order to examine the effect of ecdysteroid on virus transmission, the profile of hemolymph proteins, and progression of virus infection, were analyzed following an ecdysteroid injection of BmEGTZ- or BmNPV-infected larvae. In the BmNPV-infected larvae, ecdysteroid treatment had no apparent effect on hemolymph protein expression. This suggests that the injected ecdysteroid was inactivated by the BmNPV-expressed ecdysteroid UDP-glucosyltransferase. An Ecdysteroid injection into BmEGTZ-infected larvae increased the speed of virus-specific protein expression and virus transmission. These results suggest that ecdysteroid stimulates protein expression, which in tum results in the stimulation of virus transmission.

• International Journal of Industrial Entomology and Biomaterials
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• v.23 no.1
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• pp.123-128
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• 2011

1-Deoxynojirimycin (DNJ) is an alkaloid that is found at relatively high concentrations in mulberry leaf and tissues of the silkworm, $Bombyx$ $mori$. DNJ is a well known inhibitor of ${\alpha}$-glucosidase, an enzyme that is involved in the early stages of the $N$-linked glycoprotein synthesis pathway. ${\alpha}$-Glucosidase activity in the cell extract from $B.$ $mori$-derived Bm5 cells showed approximately 40-fold less sensitivity to DNJ than ${\alpha}$-glucosidase activity in the cell extract from $Spodoptera$ $frugiperda$-derived Sf9 cells. The replication of $B.$ $mori$ nucleopolyhedrovirus (BmNPV) was not inhibited when it was propagated in BmN cells that were grown in medium containing up to 10 mM DNJ. In contrast, the replication of $Autographa$ $californica$ multiple NPV (AcMNPV) was reduced by 67% when it was propagated in Sf9 cells that were grown in medium containing 10 mM DNJ. The viability of Bm5 and Sf9 cells that were grown in medium containing up to 10 mM DNJ was not affected. Our results suggested that the reduced replication of AcMNPV was the result of the higher sensitivity of ${\alpha}$-glucosidase activity in Sf9 cells to DNJ.

• 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

No Abstract, See Full Text

• Proceedings of the Korean Society of Sericultural Science Conference
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• 2002.10a
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• pp.44-44
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• 2002

No Abstract, See Full Text