Search results for "Bombyx mori"

Collisional mechanism of ligand release by Bombyx mori JHBP, a member of the TULIP / Takeout family of lipid transporters.

2020

International audience; Juvenile hormones (JHs) regulate important processes in insects, such as postembryonic development and reproduction. In the hemolymph of Lepidoptera, these lipophilic sesquiterpenic hormones are transported from their site of synthesis to target tissues by high affinity carriers, the juvenile hormone binding proteins (JHBPs). Lepidopteran JHBPs belong to a recently uncovered, yet very ancient family of proteins sharing a common lipid fold (TULIP domain) and involved in shuttling various lipid ligands. One important, but poorly understood aspect of JHs action, is the mechanism of hormone transfer to or through the plasma membranes of target cells. Since many membrane-…

Production performance and economic traits of silkworms (Bombyx mori L., 1758) fed with mulberry tree leaves (Morus alba, var. Ichinose) significantl…

2019

Abstract Production performance of silkworm (Bombyx mori L., 1758) play a pivotal role in sericulture industry and good quality cocoon represents the economic driver of farms. Silkworms are monophagus insects and differences between cocoon characteristics may depend both on mulberry tree leaves quality as well as on genetic selection of hybrid lines. While a huge work was carried out to identify the best feeding sources to optimize yields, genetic types of silkworms with desirable production and economic traits were studied to a limited extent to date. This experimental feeding trial was carried out using a commercial variety of mulberry tree leaves (Morus alba var. Ichinose) to feed a tota…

Zīda fibroīna izdalīšana apatītu kompozītmateriālu modificēšanai

2022

Zīda fibroīna izdalīšana apatītu kompozītmateriālu modificēšanai. Kleinberga A., zinātniskais vadītājs Dr. chem., doc. Agnese Osīte. Bakalaura darbs, 42 lappuses, 30 attēli, 10 tabulas, 53 literatūras avoti, 4 pielikumi. Latviešu valodā. Darbā veikta hidroksilapatīta sintēze, izdalīts zīda fibroīns no Bombyx mori zīda kokoniem un veikta to analīze ar FTIR, XRD u.c. metodēm. Apkopota literatūras informācija par hidroksilapatītiem, to izmantošanu un analīžu metodēm. Kā arī apkopota informācija par zīda šķiedrām, to attīrīšanas un analīžu metodēm, kā arī izmantošanu. Hidroksilapatīta kristāliskās struktūras raksturošanai tika izmantots Rentgenstaru difraktometrs. Hidroksilapatīta un zīda fibro…

Growth of human cells on a non-woven silk fibroin net: a potential for use in tissue engineering.

2003

We have examined a novel biomaterial consisting of a non-woven fibroin net produced from silk (Bombyx mori) cocoons for its ability to support the growth of human cells. Various human cells of different tissue and cell types (endothelial, epithelial, fibroblast, glial, keratinocyte, osteoblast) were examined for adherence and growth on the nets by confocal laser microscopy after staining of the cells with calcein-AM and by electron microscopy. All the cells readily adhered and spread over the individual fibers of the nets. Most of the cells were able to grow and survive on the nets for at least 7 weeks and growth not only covered the individual fibers of the net but generally bridged the ga…

Identification and cloning of odorant binding proteins from the scarab beetle Phyllopertha diversa.

1999

Abstract Wehave identified, cloned, and characterized two odorant binding proteins from the pale brown chafer, Phyllopertha diversa. One of the proteins (OBP1, 116 amino acids long) showed high amino acid identity (>90%) to two previously identified PBPs from scarab beetles. The second protein (OBP2) showed limited sequence similarity to lepidopteran and dipteran OBPs, but contained only 133 amino acids. Both proteins showed the occurrence of six highly conserved cysteines; electrospray mass spectral data suggested they are all bound in three disulfide bonds. During purification, OBP2 separated into several isoforms; N-terminal amino acid sequencing and electrospray ionization mass spectrom…

Endothelialization of a non-woven silk fibroin net for use in tissue engineering: growth and gene regulation of human endothelial cells

2004

Abstract We have previously shown that a biomaterial consisting of a non-woven fibroin net produced from silk (Bombyx mori) cocoons is an excellent scaffolding material for a wide variety of human cells of different tissue types. Endothelialization must take place for a biomaterial to be successful after implantation. Therefore, primary human endothelial cells and the human endothelial cell lines, HPMEC-ST1.6R and ISO-HAS-1, were examined for adherence and growth patterns on the fibroin nets by confocal laser scanning microscopy after vital staining of the cells and by electron microscopy. Endothelial cells adhered and spread along individual fibers of the nets and did not fill the gaps bet…

The crystal structure of a cockroach pheromone-binding protein suggests a new ligand binding and release mechanism.

2003

Pheromone-binding proteins (PBPs) are small helical proteins found in sensorial organs, particularly in the antennae, of moth and other insect species. They were proposed to solubilize and carry the hydrophobic pheromonal compounds through the antennal lymph to receptors, participating thus in the peri-receptor events of signal transduction. The x-ray structure of Bombyx mori PBP (BmorPBP), from male antennae, revealed a six-helix fold forming a cavity that contains the pheromone bombykol. We have identified a PBP (LmaPBP) from the cockroach Leucophaea maderae in the antennae of the females, the gender attracted by pheromones in this species. Here we report the crystal structure of LmaPBP a…

Characterization of Urbain, a gene expressed during Bombyx mori imaginal wing discs morphogenesis

1995

Study of the aminopeptidase N gene family in the lepidopterans Ostrinia nubilalis (Hübner) and Bombyx mori (L.): Sequences, mapping and expression

2010

Aminopeptidases N (APNs) are a class of ectoenzymes present in lepidopteran larvae midguts, involved in the Bacillus thuringiensis (Bt) toxins mode of action. In the present work, seven aminopeptidases have been cloned from the midgut of Ostrinia nubilalis, the major Lepidopteran corn pest in the temperate climates. Six sequences were identified as APNs because of the presence of the HEXXH(X)18E and GAMEN motifs, as well as the signal peptide and the GPI-anchor sequences. The remaining sequence did not contain the two cellular targeting signals, indicating it belonged to the puromycin-sensitive aminopeptidase (PSA) family. An in silico analysis allowed us to find orthologous sequences in Bo…

Nachweis von h�utungsaktiven Stoffen in isolierten Prothorakaldr�sen und Oenocyten beiBombyx mori w�hrend des 5. Larvenstadiums

1977

The content of moulting hormones has been determined in homogenates of isolated prothoracic glands and oenocytes during the 5th instar of the silkworm,Bombyx mori by means of the Calliphora bioassay. Prothoracic glands show variable activity in the production of moulting hormones, reaching a maximum near the end of the larval period. Comparable activities, but at higher levels, could be demonstrated in oenocytes. Controls with doubled quantities of tissue produced in a proportionate reaction in the bioassay. Fat bodies were inactive. Prothoracic glands and oenocytes incubated together resulted in a slower pupation index than would be expected from the sum of single determinations of oenocyt…