Prothoracicotropic hormone (PTTH) of the silkworm, Bombyx mori, was purified and its primary structure determined for the most part. From sodium dodecyl sulfate-polyacrylamide gel electrophoresis of the purified PTTH under non-reducing and reducing conditions, and the amino acid sequence and composition analyses of the carboxamidomethylated PTTH, we concluded that Bombyx PTTH has a dimeric stru...

Nuclear polyhedrosis, that is jaundice, is distinguished among other mulberry silkworm diseases by its pathogenicity. It is a powerful viral, hereditary disease of mulberry silkworm that results in mass destruction of mulberry silkworm. Polyhedrose is spread in all silk manufacturer countries and incurs the losses to sericulture more than any infectious diseases of mulberry silkworm. Viruses wh...

A restriction fragment library which covered the entire genome of Bombyx mori nuclear polyhedrosis virus (BmNPV) was constructed using plasmid vectors. By analysis of cloned and viral DNA by double digestion with endonucleases and by hybridization techniques, a complete physical map of BmNPV was constructed for BamHI, EcoRI, HindIII, KpnI, PstI and SmaI. Five regions of repeated sequences conta...

The Bombyx mori (Lepidoptera: Bombycidae) midgut undergoes remodeling during the larval-pupal metamorphosis. All metamorphic events in insects are controlled by mainly two hormones: 20-hydroxyecdysone (20E) and juvenile hormone (JH). Fenoxycarb, O-ethyl N-(2-(4-phenoxyphenoxy)-ethyl) carbamate, has been shown to be one of the most potent juvenile hormone analogs against a variety of insect spec...

Research on molecular mechanisms that viruses use to regulate the host apparatus is important in virus infection control and antiviral therapy exploration. Our previous research showed that the Bombyx mori nucleopolyhedrovirus (BmNPV) LEF-11 localized to dense regions of the cell nucleus and is required for viral DNA replication. Herein, we examined the mechanism of LEF-11 on BmNPV multiplicati...

The Domesticated silkworm, Bombyx mori, an economically important insect has been used as a lepidopteran molecular model next only to Drosophila. Compared to the genomic information in silkworm, the protein-protein interaction data are limited. Therefore experimentally identified PPI maps from five model organisms such as E.coli, C.elegans, D.melanogaster, H. sapiens, S. cerevisiae were used to...

Silk cocoons, constructed by silkmoths (Lepidoptera), are protective structural composites. Some cocoons appear to have evolved towards structural and material optimisation in order to sustain impact strikes from predators and hinder parasite ingress. This study investigates the protective properties of silk cocoons with different morphologies by evaluating their impact resistance and damage to...

Established animal models have accelerated our understanding of the mechanisms involved in lifespan determination. However, more experimental animals are required to clarify the complex mechanisms behind the phenomena of aging and lifespan. In this study, we reported the variation of lifespan in nine distinct silkworm strains. Lifespan correlated significantly with BmFoxO gene expression in the...

Serpins generally serve as inhibitors that utilize a mobile reactive center loop (RCL) as bait to trap protease targets. Here, we present the crystal structure of serpin18 from Bombyx mori at 1.65 Å resolution, which has a very short and stable RCL. Activity analysis showed that the inhibitory target of serpin18 is a cysteine protease rather than a serine protease. Notably, this inhibitiory rea...