The addition of exogenous histones has an inhibitory effect on fibroin gene transcription in posterior silk gland extracts. The histones probably disturb a process in complex formation, because when transcription complexes were constructed by preincubation of the templates with the extracts, the inhibitory effect of histones was greatly reduced. Transcription of a fibroin gene construct, pFb5' ...

Fibroin is normally composed of one H chain (350 kd) and one L chain (25 kd) which are connected by disulfide bond(s). However, the small amount of fibroin secreted into the lumen of the posterior silk gland of the Nd(2) (naked pupa) mutant does not contain L chain, although L chain mRNA is present and L chain is synthesized in the posterior silk gland cells of the mutant. In a hybrid silkworm,...

Baker, S. L., Butterworth, E. C. & Langley, F. A. (1946). Biochem. J. 40, 291. Bowes, J. H. & Kenten, R. H. (1949). Biochem. J. 45, 281. Dallemagne, M. J. (1943). La Nature chimique de Ia 8Ub8tance o0seuse. Thesis. Liege. Hammett, F. S. (1925). J. biol. Chem. 64, 409. Hess, A. F., Berliner, F. S. & Weinstock, M. (1931). J. biol. Chem. 94, 9. Lightfoot, G. H. & Coolidge, T. B. (1948). J. biol. C...

The biological performance of artificial biomaterials is closely related to their structure characteristics. Cell adhesion, migration, proliferation, and differentiation are all strongly affected by the different scale structures of biomaterials. Silk fibroin (SF), extracted mainly from silkworms, has become a popular biomaterial due to its excellent biocompatibility, exceptional mechanical pro...

Isolated silkgland ribosomes were irradiated with X-rays, and their activities to synthesize fibroin in vitro were examined. A marked decrease in their activities was observed when ribosomes were incubated at 37•Ž following X-irradiation. Per cent decrease in the ribosomal activity leveled off at 37•Ž after 30 minutes incubation . The extent of decrease was dependent on X-ray dose. Treatment of...

Various spider species produce dragline silks with different mechanical properties. The primary structure of silk proteins is thought to contribute to the elasticity and strength of the fibres. Previously published work has demonstrated that the dragline silk of Euprosthenops sp. is stiffer then comparable silk of Nephila edulis, Araneus diadematus and Latrodectus mactans. Our studies of Eupros...

We developed the novel silk fibroin-based bilayered wound dressing for the treatment of partial thickness wounds. And it showed relevant characteristics and accelerated the healing of full-thickness wounds in a rat model. This study is the clinical evaluation of the bilayered wound dressing to confirm its safety and efficacy for the treatment of split-thickness skin donor sites. The safety test...

A formulation of regenerated silk fibroin solution that can be easily functionalized and inkjet printed on numerous surfaces is developed. As an example, the inks can be printed on laboratory gloves that change color when exposed to bacteria.

We have directly compared the ability of four promoters and three polyadenylation (poly(A)) signals to direct heterologous gene expression in stably transfected Drosophila melanogaster S2 cells. We compared two constitutive Drosophila promoters, the actin 5C distal promoter and the alpha 1-tubulin promoter, with the tightly regulated Drosophila metallothionein (Mtn) promoter and the Bombyx mori...

Beta-pleated-sheet crystals are among the most stable of protein secondary structures, and are responsible for the remarkable physical properties of many fibrous proteins, such as silk, or proteins forming plaques as in Alzheimer's disease. Previous thinking, and the accepted paradigm, was that beta-pleated-sheet crystals in the dry solid state were so stable they would not melt upon input of h...