L'Unité nationale séricicole

Chavancy Gérard. L'Unité nationale séricicole. In: Le Monde alpin et rhodanien. Revue régionale d'ethnologie, n°2-3/1991. Les filières de la soie lyonnaise, sous la direction de Florence Charpigny . pp. 129-130

Les Carnets de la soie

Chavancy (Gérard) and Marié (Michel). — Les Carnets de la soie (The silk notebooks). The authors, a researcher in biology and a film director, present the project of an «ail public» film, made up of four separate parts. «La laine des arbres» (The wool of trees) is about the origins of silk and associated legends ; «Le fil du temps •> (The Thread of Time), describes, in time and space, the long process that transforms thread into silk fabrics ; «L'art de la soie» (The art of silk) gives the creators the possibility to talk about their passion for silk ; <• Le ver à soie : profession modèle » (The silkworm : a model profession) présents biological research carried out thanks to the silkworm, a laboratory animal. Le Monde alpin et rhodanien, 2-3e trimestres 1991, Les filières de la soie lyonnaise, pp. 149 à 154.Chavancy (Gérard) et Marié (Michel). — Les Carnets de la soie. Les auteurs, un chercheur en biologie et un cinéaste, présentent le projet d'un film «tout public», conçu en quatre parties autonomes. «La laine des arbres» évoque les origines de la soie et les légendes qui y sont attachées ; «Le fil du temps» décrit, dans le temps et dans l'espace, le long processus qui transforme le fil en étoffe ; «L 'art de la soie» donne la parole aux créateurs qui évoquent leur passion pour la soie ; «Le ver à soie : profession modèle» présente les recherches biologiques menées grâce au ver à soie, animal de laboratoire. Le Monde alpin et rhodanien, 2-3e trimestres 1991, Les filières de la soie lyonnaise, pp. 149 à 154.Chavancy Gérard, Marié Michel. Les Carnets de la soie. In: Le Monde alpin et rhodanien. Revue régionale d'ethnologie, n°2-3/1991. Les filières de la soie lyonnaise, sous la direction de Florence Charpigny . pp. 149-154

Effect of tRNA pool balance on rate and uniformity of elongation during translation of fibroin mRNA in a reticulocyte cell-free system

Unsuccessful attempts to synthesize complete fibroin chains in vitro were previously made in heterologous cell-free system [3]. In the present work, we succeeded to obtain complete translation of purified fibroin mRNA in a rabbit reticulocyte lysate. Whilst this work was being completed [1], similar results were published by Lizardi et al. [4]. The synthesis of full-sized molecules of fibroin (M.W. 360,000) was achieved by adding tRNA from the posterior silk gland to the cell-free system. With tRNA from other sources, both the translation rate and the amount of complete fibroin chains dropped. This effect of tRNA is situated at the elongation level. Analysis of cell-free synthesized products by polyacrylamide gel electrophoresis shows that smaller discrete polypeptides are accumulated after 120 minutes of incubation. These polypeptides correspond to growing fibroin chains. This pattern of translation products suggests that elongation might decelerate at specific sites of the fibroin mRNA. These results show that a tRNA pool adjusted to mRNA codon frequency is required to obtain the maximal average elongation rate. A stochastic model based on random acceptance of tRNA at the ribosomal A site for the codon-anticodon recognition process can explain this phenomenon. It can also explain the occurrence of the unfinished discrete fibroin polypeptides during in vitro translation. © 1981 Masson, Paris.SCOPUS: ar.jinfo:eu-repo/semantics/publishe

A helium burst biolistic device adapted to penetrate fragile insect tissues

To compensate for the extremely low penetration efficiency of the original PDS/1000-He Bio Rad biolisticreg; device and the deleterious blast effect, design modifications have been made to the launching module. These modifications were evaluated on Bombyx mori embryos and fragile tissues, such as oocytes and imaginal wing disks. The original floppy macrocarrier was replaced by a rigid macrocarrier to avoid the effects of the helium blast. The efficiency of the gene gun bombardment was reinforced by the addition of a focusing nozzle. The reduced blast effect allowed us to carry out high-pressure shootings to small organs with improved penetration. This system allowed potentially all the internal embryonic tissues to be transfected with optimal survival rates. The new module was effective on tissues that are difficult to transfect, such as the epithelial wing disk that is covered by a peripodial membrane, and the ovarian follicle cells that lie under the ovariole cell membrane. The new macrocarrier allowed both an aqueous delivery of particles and an ethanolic dry delivery. No significant differences were noted between these two modes of delivery. The major improvement is the possibility of high pressure shooting correlated with appreciable penetration and a weak blast effect

Novel genes differentially expressed between posterior and median silk gland identified by SAGE-aided transcriptome analysis.

International audienceSerial analysis of gene expression (SAGE) profiles, from posterior and median cells of the silk gland of Bombyx mori, were analyzed and compared, so as to identify their respective distinguishing functions. The annotation of the SAGE libraries was performed with a B. mori reference tag collection, which was extracted from a novel set of Bombyx ESTs, sequenced from the 3' side. Most of the tags appeared at similar relative concentration within the two libraries, and corresponded with region-specific and highly abundant silk proteins. Strikingly, in addition to tags from silk protein mRNAs, 19 abundant tags were found (≥0.1%), in the median cell library, which were absent in the posterior cell tag collection. With the exception of tags from SP1 mRNA, no PSG specific tags were found in this subset class. The analysis of some of the MSG-specific transcripts, suggested that middle silk gland cells have diversified functions, in addition to their well characterized role in silk sericins synthesis and secretion