Abstract Recent advancements in genetic engineering technology have led to the development of CRISPR interference (CRISPRi) as a precise tool for regulating gene expression. When CRISPR/dCas9 is fused with transcriptional repressors, the system can robustly silence endogenous gene expression. The CRISPR/Cas9 tool is a promising alternative in organisms (e.g., Bombyx mori ) that do not respond to traditional gene suppression techniques, such as RNA interference (RNAi). However, transcriptional re...
Abstract DNA methylation has been proven to play roles in regulating gene expression, cell fate, disease determination, and chromatin architecture organization in mammals and plants, and is a significant component of epigenetic modification. Compared to mammals or plants, the status and function of DNA methylation are poorly understood in insects, which is partially due to the lack of efficient manipulation tools. In this study, we show that fusion protein of catalytically inactive Cas9 (dCas9) ...
Abstract Sericins are large proteins with molecular weights >70 kDa. Three sericin genes were reported in the silkworm, including sericin 1 , sericin 2 and sericin 3 . In this study, we have identified a new sericin gene and designated it as sericin 4 . The sequence, exon-intron structure, alternative splicing, and translation products of this gene have been described in this study. Quantitative RT-PCR analysis indicates that sericin 4 is expressed in the middle silk gland. Immunofluorescence re...
The silk gland synthesizes and secretes a large amount of protein and stores liquid silk protein at an extremely high concentration. Interestingly, silk proteins and serine protease inhibitors are orderly arranged in the silk gland lumen and cocoon shells. Silk fiber formation and the spinning mechanism have not been fully elucidated. Therefore, we conducted a comparative transcriptome analysis of seven segments of the single silk gland to characterize internal changes in the silk gland during t...
Ecdysteroid UDP glucosyltransferase (EGT) is a baculovirus-encoded protein which can hinder the normal molting of insects by inactivating 20-hydroxyecdysone (20E). Here we expressed EGT in the last-instar silkworm larvae using the GAL4/ UAS system. Compared with the control, for the EGT overexpressed silkworm, the hemolymph 20E content was significantly decreased, the feeding and spinning periods of the last-instar silkworm larvae were extended, the cocoon shell ratio was significantly increased...