Weaving Women Silk Production Bound up in Fact and Legend

IN antiquity, the earliest materials for weaving were flax and pueraria lobata. Women invented weaving and were the original weavers. They picked fibers of wild flax and wild pueraria Iobata and pressed them into thin threads with a pottery or stone wheel. Then they wove the threads

Comprehensive silk gland multi-omics comparison illuminates two alternative mechanisms in silkworm heterosis

Heterosis is a common phenomenon in plants and animals with diverse underlying mechanisms.Here,we applied two widely used silkworm hybrid systems and performed multi-omics analysis to identify possible intrinsic associations between different hybrid strategies and epigenetic mechanisms with silkworm heterosis.We found significant differences in the silk gland transcriptomic landscape between the two systems,including differentially expressed genes and expression patterns in the hybrid offspring compared to their parents.In the quaternary hybrid system,hybrid vigor was primarily due to upregulated genes and the parent-dominant upregulated expression pattern,involving multiple transport processes,cellular nitrogen compound catabolism,glucose metabolism,and tricarboxylic acid cycle.In the binary system,hybrid vigor was mainly due to the down-regulated genes and transgressively down-regulated expression pattern,mainly involving basic nitrogen synthesis metabolism and body function.We also demonstrated that DNA methylation may affect hybrid vigor by regulating the expression of several heterosis-related genes.Thus,this study revealed two alternative mechanisms that may contribute to silkworm heterosis,both of which facilitate the efficient utilization of energy and nitrogen for silk production.

Pricing Power of China's Cocoon and Silk Products in International Market:An Empirical Analysis Based on International Market Power

Do China＇s silk products only have advantage in number but no pricing power in international market？ In this paper, we used the residual demand elasticity model to estimate the international market power of China＇s silk products. The empirical results revealed that China＇s raw material products such as natural silk products and semi-finished products such as satin products had certain market power in the main export markets, but the finished silk products such as woman＇s blouse or shirts and shawls had no market power in the target markets including USA and Germany. The scale economy from resource endowment and great market share are the base of the international market power of natural silk products. The advantage from industry agglomeration and great market share are the source of the international market power of satin products. Technical bottlenecks and inefficiency in brand building are the cause of unobvious international market power of China＇s finished silk products, and the competition from Italy and France has increased the difficulty to enhance market power. In order to consolidate and improve the international market power of China＇s silk products, it is suggested to stabilize the production scale and strengthen industrial base, to speed up the resources integration and optimize the industrial distribution, to strengthen science and technology innovation and adjust product structure, to speed up the brand construction and enhance the influence of brand, and to enlarge the scale of organization and achieve scale economies.

G-quadruplex is involved in the regulation of BmSGF1 expression in the Silkworm, Bombyx mori

Advanced DNA structures,such as the G-quadruplex(G4)and the i-motif,are widely but not randomly present in the genomes of many organisms.A G4 structure was identified in the promoter of the silk gland factor-1 gene(SGFI),which is the main regulatory gene for silk production in Bombyx mori.In this study,a BmSGF1 G4^(-/-)ho-mozygous mutant was generated with the G4 sequence knocked out.The promoter activity of BmSGF1 was lowered in the BmSGF1 G4^(-/-)mutant.Pyridostatin(PDS)stabilized the G4 structure and increased the promoter activity of BmSGF1,whereas anti-sense oligonu-cleotide(ASO)complementary to the G4 sequence suppressed the promoter activity of BmSGF1.Compared with wild-type larvae,the deletion of the BmSGF1 G4 structure de-creased both the expression of BmSGF1 and the fibroin heavy chain gene BmFib-H in the posterior silk gland and the weight of the cocoons.Overall,these results suggest that the promoter G4 structure of BmSGFI participates in the transcription regulation of the BmSGFl gene in the silkworm.