Gene expression and immunolocalization of chitin deacetylase BmCDA2 in silkworm / 生物工程学报

Deacetylation of chitin is closely related to insect development and metamorphosis. Chitin deacetylase (CDA) is a key enzyme in the process. However, to date, the CDAs of Bombyx mori (BmCDAs), which is a model Lepidopteran insect, were not well studied. In order to better understand the role of BmCDAs in the metamorphosis and development of silkworm, the BmCDA2 which is highly expressed in epidermis was selected to study by bioinformatics methods, protein expression purification and immunofluorescence localization. The results showed that the two mRNA splicing forms of BmCDA2, namely BmCDA2a and BmCDA2b, were highly expressed in the larval and pupal epidermis, respectively. Both genes had chitin deacetylase catalytic domain, chitin binding domain and low density lipoprotein receptor domain. Western blot showed that the BmCDA2 protein was mainly expressed in the epidermis. Moreover, fluorescence immunolocalization showed that BmCDA2 protein gradually increased and accumulated with the formation of larval new epidermis, suggesting that BmCDA2 may be involved in the formation or assembly of larval new epidermis. The results increased our understandings to the biological functions of BmCDAs, and may facilitate the CDA study of other insects.

Development of a CRISPR/Cpf1 gene editing system in silkworm Bombyx mori / 生物工程学报

The CRISPR/Cas9 gene editing system has been widely used in basic research, gene therapy and genetic engineering due to its high efficiency, fast speed and convenience. Meanwhile, the discovery of novel CRISPR/Cas systems in the microbial community also accelerated the emergence of novel gene editing tools. CRISPR/Cpf1 is the second type (V type) CRISPR system that can edit mammalian genome. Compared with the CRISPR/Cas9, CRISPR/Cpf1 can use 5'T-PAM rich region to increase the genome coverage, and has many advantages, such as sticky end of cleavage site and less homologous recombination repair. Here we constructed three CRISPR/Cpf1 (AsCpf1, FnCpf1 and LbCpf1) expression vectors in silkworm cells. We selected a highly conserved BmHSP60 gene and an ATPase family BmATAD3A gene to design the target gRNA, and constructed gHSP60-266 and gATAD3A-346 knockout vectors. The efficiency for editing the target genes BmATAD3A and BmHSP60 by AsCpf1, FnCpf1 and LbCpf1 were analyzed by T7E1 analysis and T-clone sequencing. Moreover, the effects of target gene knockout by different gene editing systems on the protein translation of BmHSP60 and BmATAD3A were analyzed by Western blotting. We demonstrate the CRISPR/Cpf1 gene editing system developed in this study could effectively edit the silkworm genome, thus providing a novel method for silkworm gene function research, genetic engineering and genetic breeding.

Verificação da interferência do solvente propilenoglicol sobre o efeito da própolis na produção de lagartas de Bombyx mori L. (Lepidoptera: bombicidae) comparado ao extrato alcoólico de própolis / Interference of propyleneglycol solvent on the effect of propolis in the production of silkworm Bombyx mori L. (Lepidoptera: bombicidae) compared to propolis alcoholic extract / Verificación de la interferencia del solvente propilenoglicol sobre el efecto de propóleos en la producción de gusano de seda Bombyx mori L. (lepidoptera: bombicidae) comparado al extracto alcohólico de propóleos

Este experimento foi realizado no Laboratório de Sericicultura, no Campus Sede da Universidade Paranaense (UNIPAR) de Umuarama, no período de fevereiro a outubro de 2011, com o objetivo de verificar o efeito da própolis em diferentes dosagens na alimentação durante o desenvolvimento biológico do bicho-da-seda (Bombxy mori L.). O método empregado na parte experimental foi a pulverização do extrato glicólico de própolis, diluído em 500mL de água destilada nas folhas de amoreira, nas seguintes dosagens, água-controle, 25mL, 30mL, 35mL e 40mL compondo os tratamentos: controle, T1 , T2 , T3 e T4 respectivamente. As folhas de amoreira foram fornecidas cinco vezes ao dia, durante o manejo alimentar. Verificou-se, pelos resultados obtidos, que as diferentes dosagens de própolis utilizadas não interferiram no ganho de peso das lagartas, no peso dos casulos verdes, no peso da casca sérica e crisálidas, quando comparado ao tratamento controle, mas quando se compara o Controle e T4 do ensaio da primavera, respectivamente, para os teores de seda bruto e líquido, há resultados significativos. Portanto, verificou-se que o extrato glicólico de própolis, em dosagens de 40mL, pode prejudicar o teor líquido de seda em uma produção de casulos, trazendo resultados pouco apreciados dentro da sericicultura...

This experiment was performed at the Laboratory of Sericulture, at the main campus of University Paranaense (UNIPAR), in the city of Umuarama, from February to October 2011, in order to verify the effect of different doses of propolis in feeding during the biological development of silkworm (Bombyx mori L.). The method used in the experiment was the spraying of propolis glycolic extract dissolved in 500-mL distilled water on the mulberry leaves in the following water- -control dosages: 25mL, 30mL, 35mL and 40mL related to the treatment controls T1, T2, T3 and T4, respectively. Mulberry leaves were provided five times a day for feeding management. The results obtained showed that the different dosages of propolis used did not affect the weight gain of the larvae, the weight of green cocoons, shells and pupae when compared to the control treatment. However, when comparing the control and T4 from the Spring assay, respectively, to the levels of crude and net silk, significant results were noted. Thus, it can be concluded that propolis glycolic extract in 40-ml dosages may impair the net silk content in a cocoon production, presenting negative results in sericulture...

: Este experimento se llevó a cabo en el Laboratorio de Sericultura, Campus Sede de la Universidad Paranaense (UNIPAR) de Umuarama, en el período de febrero a octubre de 2011, con el fin de verificar el efecto de propóleos en diferentes concentraciones en la alimentación durante el desarrollo biológico del gusano de seda (Bombyx mori L.). El método utilizado en el experimento fue la pulverización de extracto glicólico de propóleos, disuelto en 500 ml de agua destilada en las hojas de morera, en las siguientes dosis, agua control, 25 mL, 30mL, 35 mL, y 40 mL componiendo los tratamientos: control T1 , T2 , T3 e T4 respectivamente. A las hojas de morera se les han dado cinco veces al día, durante el manejo alimentar. Se verificó, por los resultados obtenidos, que las diferentes dosis de propóleos utilizados no afectaron en la ganancia de peso de los gusanos, en el peso de los capullos verdes, en el peso de la cáscara sérica y crisálidas, en comparación con el tratamiento de control, pero cuando se compara el Control y T4 del ensayo de la primavera, respectivamente, para los niveles de seda cruda y líquida, hay resultados significativos. Por lo tanto, se encontró que el extracto glicólico de propóleos, en dosis de 40 mL, puede perjudicar la concentración líquida de seda en una producción de capullos, trayendo resultados poco apreciados dentro de la sericultura...

Immune enhancement activities of silk lutein extract from Bombyx mori cocoons

BACKGROUND: Declining immune function poses an important clinical challenge worldwide and supplementation with natural products that possessing immune enhancing properties is a promising approach for preventing or delaying immune function decline. Cocoons from yellow silkworms are a significant source of lutein, and this unexplored silk extract could be a viable alternative source for dietary lutein. This study assessed immunomodulatory activities of the silk lutein extract. Female BALB/c mice orally received lutein, either as silk or marigold extracts (10 or 20 mg/kg daily), or vehicle only (1% tween 80 in PBS pH 7.4) for 4 weeks. Natural killer (NK) cell activity, specific antibody production, lymphocyte subpopulations, mitogen-induced lymphocyte proliferation, and cytokine production were examined. RESULTS: Silk lutein extract increased NK cell activity, and the effect was dose-related whereas marigold lutein extract was ineffective. Silk lutein extract dose-dependently enhanced antibody production in pre-immunized mice but marigold lutein extract had no effect. Feeding with silk lutein extract increased the populations of CD3+ and CD4 + CD3 + cells. Silk lutein extract also stimulated concanavalin A- and lipopolysaccharide-induced proliferations of T and B lymphocytes, respectively. Moreover, silk lutein extract increased IL-2 and IFN-γ production while the effect of marigold lutein extract was undetectable. CONCLUSIONS: Together, silk lutein extract enhanced both innate and adaptive immune functions. This preparation may prove to be an effective supplement for strengthened immunity.

Protective effect of silk lutein on ultraviolet B-irradiated human keratinocytes

Carotenoids are efficient antioxidants that are of great importance for human health. Lutein and zeaxanthin are carotinoids present in high concentrations in the human retina which are involved in the photoprotection of the human eye. Lutein may also protect the skin from ultraviolet (UV)-induced damage. The present study investigated the protective effect of lutein extracted from yellow silk cocoons of Bombyx mori on human keratinocytes against UVB irradiation. A human keratinocyte cell line and primary human keratinocytes were used to investigate the UVB protection effects of silk lutein and plant lutein. Silk lutein showed no cytotoxicity to keratinocytes. Treatment with silk lutein prior to UVB irradiation enhanced cell viability and cell proliferation, and reduced cell apoptosis. The protective effects of silk lutein may be superior to those of plant lutein. Silk lutein may have a benefit for protection of keratinocytes against UVB-irradiation.

Fuel mobilization for energy metabolism in the silkmoth, Bombyx mori, during reproductive processes.

Flight muscles of male moth, B. mori seem to utilize carbohydrate preferentially as a source of energy for all its acrobatic movements during the search for female moth. Depletion of triacylglycerol from flight muscles without affecting its level from fat body suggests that this lipid fraction serves as a source of energy in flight muscles during insemination processes. Significant depletion of triacylglycerol and glycogen from flight muscles of female moth after egg laying indicates that they are used to meet the energy requirement of female during oviposition activity. Depletion of proteins from flight muscles of male and female insects suggest that these proteins are transported to the accessory reproductive glands to meet their protein demand.