• International Journal of Industrial Entomology and Biomaterials
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• 제6권2호
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• pp.107-113
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• 2003

Analysis of combining ability is a widely used biometrical tool to select promising parents and hybrids, to determine the kinds and relative magnitudes of genetic variability among hybrids as well as to forecast yield attributes in early breeding generations both in plants and animals. Various statistical approaches like Jinks and Hayman (1953), Griffing (1956), Kempthorne (1957) etc. have been extensively applied in plants. These approaches have also been tried in the mulberry silkworm, Bombyx mori L. In the present review, an attempt has been made to collect most of the studies carried out on combining ability in silkworm at one place and make it available to the scientists engaged in sericultural research.

• International Journal of Industrial Entomology and Biomaterials
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• 제15권2호
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• pp.137-143
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• 2007

Lactate dehydrogenase (LDH) is a ubiquitous enzyme that plays a significant role in the clinical diagnosis of pathologic processes. Discovery of the LDH (BmLDH) gene in B. mori may shed light on its role in the biology of Lepidoptera species, and afford further understanding of the function of the enzyme. In this study, we used the bioinformatics tools to identify LDH gene in B. mori. Sequence analysis showed that BmLDH cDNA contains a 996 bp open reading frame, encoding 331 AA proteins, with seven introns. Compared with hHLDH (human heart LDH), BmLDH contained the same key active sites. Domain search and protein fold recognition analyses provide compelling evidences that the deduced protein is a LDH. Using the computer program MEGA3, we conducted a search for homologs of BmLDH among many eukaryotic species and confirmed that the BmLDH was conserved in all organisms investigated. This gene has been registered in GenBank under the accession number EU000385.

• International Journal of Industrial Entomology and Biomaterials
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• 제6권1호
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• pp.27-31
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• 2003

Infectious flacherie of silkworm Bombyx mori is caused by B. mori infectious flacherie virus (BmIFV) and causes severe crop loss to sericulturists. In the present study, a colloidal textile dye-based dipstick immunoassay is developed for the detection of infectious flacherie in silkworms. Colloidal textile dye (blue D2R) with Aλ$_{max}$ at 620 nm was sensitised with 500 $\mu\textrm{g}$/ml of purified anti-BmIFV IgG. The dye-antibody reagent detects purified antigen up to 10 ng/ml and BmIFV infection in diseased larval extracts $(up to a dilution of {10^-5})$ and faecal matter extracts $(up to a dilution of {10^-2})$ by forming clear blue dot within 30 min. It was observed to be stable for three months period at $4^{\circ}C$. The efficacy of textile dye-based dipstick immunoassay was on pay with HRP-based dipstick immunoassay and fluorescent antibody test, and better than latex agglutination and ouchterlony tests in the detection of BmIFV The dye-based dipstick immunoassay method provides a simple, sensitive and less expensive test for the detection of BmIFV infection in silkworms.s.

• International Journal of Industrial Entomology and Biomaterials
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• 제6권1호
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• pp.99-102
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• 2003

A cDNA of novel immulectin homologue (BmIML), a C-type lectin, was cloned from the silkworm, Bombyx mori. The immulectin cDNA is an open reading frame of 921 bp encoding 307 amino acid residues. The deduced amino acid sequence from the BmIML cDNA contains two C-type carbohydrate recognition domains (CRDs). The BmIML was most similar (61 % protein sequence identity) to the M. sexta immulectin-1, whereas BmIML showed relatively lower identity to the B. mori lipopolysaccharide-binding protein (25% protein sequence identity). These features of BmIML indicate that BmIML is a novel member of C-type lectin superfamily. Northern blot analysis revealed that the BmIML is specifically expressed in the fat body of B. moli larvae.

• International Journal of Industrial Entomology and Biomaterials
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• 제2권1호
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• pp.61-64
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• 2001

Ubiquitin can be covalently attached to cellular proteins as a post-translational modification rind is involved in metabolic stresses, such as bent shock and immune response. We have isolated and sequenced a cDNA encoding ubiquitin from the silkworm, Bombyx mori. The insert in the clone is 533 nucleotide long with an open reading frame of 387 nucleotides that encodes a protein of 129 amino acids with a molecular weight of 14.8 kDa. The amino acid sequence shared high homology with the ubiquitins known so far, The result of dot blot hybridization showed that the B. mori ubiquitin gene is up-regulated upon f. rofi infection, suggesting that the B. mori ubiquitin plays an immune-related role.

• International Journal of Industrial Entomology and Biomaterials
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• 제11권2호
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• pp.107-111
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• 2005

Impact of microsporidian infection and season on reproductive potential of Bombyx mori L. was investigated in the laboratory. Microsporidian infection significantly (P<0.01) reduced fecundity and hatching and increased sterility and mortality of eggs. Among the microsporidia, Nosema sp. 2 infected silkworm produced eggs with least fecundity and hatching percent as well as highest dead and sterile eggs followed by Nosema sp. 1 and N. bombycis. Microsporidia, in general, significantly reduced fecundity and hatching percent of eggs and increased number of dead and sterile eggs in all the three seasons except N. bombycis in July - August (S3) and Nosema sp. 2 in January February (S1). Since, seed production is the anchor sheet of mulberry sericulture, coefficient of egg lying is considered as an important aspect and the industry quite often facing shortage of disease free layings. The present study indicates that B. mori is more susceptible to microsporidia during S2 followed by S3 and S1 and Nosema sp2. is most virulent followed by Nosema spl. and N. bombycis.

• International Journal of Industrial Entomology and Biomaterials
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• 제11권1호
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• pp.49-55
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• 2005

Two BC1 group, c108 $\times$ (p50 $\times$ c108) and p50 $\times$ (p50 $\times$ c108), one group of F$_{2}$ progeny, (p50 $\times$ c108) F$_{2}$ ,and 3 SSR markers, F10539, FlO626 and FlO618 were used to test the hereditary properties of SSR markers in silkworm. FI0539, FlO626 were proved to be linkage, and FlO618 was proved to be independent to those two markers. According to Mendel's law, the recombinant value between F10539, FlO626 was calculated in all of these groups, and they were 8.55$\%$ (c108BC1), 8.02$\%$ (p50BC1) and 7.81 $\%$ (F$_{2}$) respectively. There was dominant difference among the crossing-over value using paired-samples tests by SPSS 10.0 software. This research proved that SSR markers were co-dominant in B. mori too, and F 2 progeny could be used to construct SSR linkage map although B. mori lacked of crossing over in females.

• International Journal of Industrial Entomology and Biomaterials
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• 제5권1호
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• pp.1-12
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• 2002

Ecophysiologically diapause represents a syndrome of physiological and biochemical characteristics, all of which ensure survival during a long period of dormancy. Since, silkworm enters diapause as embryo at the early embryonic stage, the duration of egg life depends on the duration of embryonic diapause. The nature of diapause in silkworm, Bombyx mori, is primarily determined by genetic characters and endocrinologicnl mechanisms, mediated by environmental factors such as temperature and photoperiod. Hibernating potency value besides nucleic acid and carbohydrate metabolism, production and utilization of sorbitol are also equally responsible for induction, initiation, determination, maintenance and termination of diapause. Embryonic diapause in Bombyx moir, induced by active secretion of sub-oesophageal ganglion is attributed to hormonal system and metabolic adjustment, which serves to bring about a new physiological state. Metabolic conversion of trehalose to glycogen at induction, glycogen to sorbitol at initiation and sorbitol to glycogen at termination of diapause is correlated and in each metabolic shift a key enzyme becomes active in response to hormonal and environmental stimulation. An attempt has been made in this review article to discuss briefly the nature of embryonic diapause, influence of various factors on diapause nature, hormonal mechanism of diapause besides biochemical composition of egg, nucleic acid and carbohydrate metabolism, production and utilization of sorbitol in relation to induction, determination, maintenance, initiation and termination of diapause in the silkworm, Bombyx mori.

• International Journal of Industrial Entomology and Biomaterials
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• 제23권1호
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• pp.137-141
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• 2011

A previous data was provided information for tissuespecific expression genes by means of whole-genome oligonucleotide microarray in the silkworm. We analyzed the tissue-specific expression patterns in the hemocyte tissue on 5 days of 5th instar larvae during the development of $B.$ $mori$. Total 5 candidates pick out from the $Bombyx$ $mori$ Microarray Database (BmMDB; http://silkworm.swu.edu.cn/microarray). To verify the hemocyte-specific expression, we analyzed by semi-quantitative and real-time quantitative RT-PCR using the highly expressed endogenous $Actin$ RNA as an intrinsic reference. In this study, we confirmed that one gene-sw17255- out of 5 candidates expressed in the hemocyte tissue, which was consistent with the previous data. Circulating hemocytes in the body fluid of the $B.$ $mori$ are most powerful target organ for producing biomaterials. We need further studies to find hemocyte-specific promoter region from sw17255 gene. Finally, this result can be applied in creating transgenic silkworms as a biomedical insect.

• BMB Reports
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• 제49권4호
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• pp.232-237
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• 2016

Mulberry tree twigs (Ramulus mori) contain large amounts of oxyresveratrols and have traditionally been used as herbal medicines because of their anti-inflammatory properties. However, the signaling mechanism by which R. mori exerts its anti-inflammatory action remains to be elucidated. In this study, we observed that R. mori ethanol extracts (RME) exerted an inhibitory effect on the lipopolysaccharide (LPS)-induced production of the pro-inflammatory cytokine interleukin-6 (IL-6) in Raw264.7 macrophage cells. Additionally, RME inhibited IL-6 production by blocking the leukotriene B₄ receptor-2 (BLT2)-dependent-NADPH oxidase 1 (NOX1)-reactive oxygen species (ROS) cascade, leading to anti-inflammatory activity. Finally, RME suppressed the production of the BLT2 ligands LTB4 and 12(S)-HETE by inhibiting the p38 kinase-cytosolic phospholipase A₂-5-/12-lipoxygenase cascade in LPS-stimulated Raw264.7 cells. Overall, our results suggest that RME inhibits the 'BLT2 ligand-BLT2'-linked autocrine inflammatory axis, and that this BLT2-linked cascade is one of the targets of the anti-inflammatory action of R. mori.